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Speaker 1: Hey, Daniel, what's the first thing you think about when

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Speaker 1: you see something in space you don't understand. Well, my

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Speaker 1: first hope is always aliens. But my first thought is

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Speaker 1: that it's probably a boring Mistand so as a scientist,

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Speaker 1: your mind goes straight to the most dramatic explanation. Yeah,

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Speaker 1: we're all hoping that somebody out there hits the science jackpot.

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Speaker 1: Everybody wants to find the thing that frocks the world. Yeah,

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Speaker 1: you know, people might not realize that science is a

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Speaker 1: little bit like playing the lottery. It's mostly wrong numbers,

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Speaker 1: but occasionally you get lucky and you win the alien jackpot.

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Speaker 1: What's the price you might need to get wiped out? Yeah? Maybe,

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Speaker 1: but think about what we might learn along the way

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Speaker 1: in our dying moments. I am more hammy cartoonists and

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Speaker 1: the creator of PhD comments. Hi, I'm Daniel. I'm a

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Speaker 1: particle physicist, and I'm constantly on the hunt for something

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Speaker 1: weird in science. Not in your department, in science in general.

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Speaker 1: There's plenty of weird things in your department, weird stuff

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Speaker 1: growing where it shouldn't be. But no, I'm looking for

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Speaker 1: weird stuff in the data, hoping to win that jackpot

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Speaker 1: is your data like it's a scratch of kind or

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Speaker 1: like you make up the numbers. No, we are just

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Speaker 1: looking at particles smashing together and hoping that something that

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Speaker 1: comes out of it is unexplained. It's weird, it's something

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Speaker 1: that our current theories of physics do not predict. Well,

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Speaker 1: congratulations to all of you because you've won the jackpot.

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Speaker 1: You are listening to our podcast Daniel and Jorge Explain

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Speaker 1: the Universe, a production of I Heart Radio. And your

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Speaker 1: prize is that you get to hear all about the incredible,

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Speaker 1: amazing mysteries of our universe, all the weird stuff that's

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Speaker 1: going on out there, all the little hints we have

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Speaker 1: about weird stuff that might be going on that could

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Speaker 1: be clues that reveal deep secrets about the nature of reality. Yeah,

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Speaker 1: and just like a real lottery, this episode might be

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Speaker 1: a winner or a dud. We'll find out. We'll have

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Speaker 1: to scratch off the surface. The price is the same

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Speaker 1: either way. That's right. The price is right meaning nothing,

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Speaker 1: You get what you pay for. But yes, science is

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Speaker 1: full of interesting mysteries out there, and it does happen

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Speaker 1: a lot, doesn't it. Daniel, did the scientists look out

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Speaker 1: into the world, or or try an experiment or do

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Speaker 1: something and things don't happen the way you expect them

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Speaker 1: to happen. Yep, everybody out there in graduate school knows

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Speaker 1: that no experiment goes right the first time. But usually

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Speaker 1: the reason you've got a weird result is that you

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Speaker 1: messed it up a little bit. You didn't calibrate things,

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Speaker 1: or you plug something in backwards, or you misread your

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Speaker 1: instrument or something. Usually there's a conventional explanation. But what

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Speaker 1: we're all looking for are those moments when you've done

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Speaker 1: everything correctly but the answer is not what you expected. Yeah,

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Speaker 1: don't they say that the real moments in science or

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Speaker 1: not the eureka moments, but them that's interesting moments exactly

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Speaker 1: wait a minute moment. There are sometimes those moments. There's

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Speaker 1: a fantastic audio tape that's floating out there of recording

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Speaker 1: of two astronomers listening to one of the first pulsars

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Speaker 1: ever seen. They happen to be recording themselves for reasons

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Speaker 1: I don't know, while they were observing, and you can

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Speaker 1: hear them going, wait a second, look at this, Oh

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Speaker 1: my gosh, is that what we think it is? WHOA

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Speaker 1: that's interesting. Really, it's for real. Wasn't acted out so

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Speaker 1: those especially they were being recorded. It's for real, it's

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Speaker 1: for real. I encourage you to go out there and

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Speaker 1: check it out. In fact, maybe we'll dig it out

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Speaker 1: for our episode that's coming up on how pulsars were discovered.

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Speaker 1: But yeah, most moments of scientific discovery like, dang it,

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Speaker 1: my experiment didn't work. Well, maybe there's a better explanation,

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Speaker 1: you know, after you check off all the boring explanations.

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Speaker 1: Sometimes it's an exciting, fascinating explanation. Something new might be

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Speaker 1: going on, or sometimes it's something routine. It could be

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Speaker 1: either one absolutely and people might remember few years ago

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Speaker 1: we thought we had discovered new trinos going faster than

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Speaker 1: the speed of light. I won't say we there because

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Speaker 1: I wasn't among the group of people I thought that

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Speaker 1: was real. And humanity does something good, it's the royal

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Speaker 1: we including when they mess it up, it's them, it's

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Speaker 1: the Italians, them Italians. I won't touch that. But as

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Speaker 1: soon as that paper came out and I saw that

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Speaker 1: it had been written in Microsoft Word, I was like, no,

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Speaker 1: there's something wrong with this paper. What do you mean?

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Speaker 1: I wrote all my papers in Microsoft word. Yeah, point made.

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Speaker 1: Actually I wrote them in Adobie FrameMaker, which tell you

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Speaker 1: how old I am A little bit. Wow. That really

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Speaker 1: does teach you. But usually, as in the case of

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Speaker 1: the Fast and the Lighten New Trinos, is just a mistake.

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Speaker 1: In that case, they forgot to plug a cable incorrectly

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Speaker 1: and so their calibration was wrong and they mismeasured the speed.

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Speaker 1: But sometimes these are famous experiments in the history of physics.

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Speaker 1: We see something we don't understand and it's actually a clue.

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Speaker 1: It's the first hint of a dramatic realization of uncovering

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Speaker 1: something we had no idea about. And a great example

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Speaker 1: is the photoelectric effect, which was an experiment around a

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Speaker 1: hundred and twenty years ago that was the first clue

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Speaker 1: that the universe was quantum mechanical. Yes, it was very

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Speaker 1: illuminating and electrifying at the same time for humanity and

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Speaker 1: very effective. Yeah. So today we'll be talking about one

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Speaker 1: such mystery in science, and in particular in space science

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Speaker 1: that happened a few years ago. Daniel right, how long

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Speaker 1: ago was this or is it still ongoing? It was

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Speaker 1: resolved a few years ago, but it went on for

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Speaker 1: several decades. This is an outstanding mystery that puzzled people,

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Speaker 1: that caused them to dig deep into their attic of

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Speaker 1: ideas for possible boring and exciting explanations for what could

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Speaker 1: be happening to this spacecraft. Yes, it involves spacecrafts and

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Speaker 1: planets and basically just need toward space and mystery. And

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Speaker 1: it's an interesting journey right here. Amazingly, there's almost no

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Speaker 1: talk of aliens in this whole topic. Not yet. It

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Speaker 1: spressed to surface Daniel and see if we can win

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Speaker 1: the library here so to be on the program, we'll

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Speaker 1: be talking about what is the Pioneer anomaly. Now, it's anomaly, right,

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Speaker 1: not animone, Just get confused. It's not an underwater sea creature.

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Speaker 1: It's not something you want deep fried and served before

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Speaker 1: your dinner. It's an anomaly. It's something that's not understood,

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Speaker 1: that's anomalous, and it's something that happened in space around

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Speaker 1: what time. Well, it has to do with the Pioneer spacecraft,

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Speaker 1: which was launched in the seventies and has one of

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Speaker 1: these incredible careers. You know, they expected to go on

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Speaker 1: for several years and then it operated for decades and

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Speaker 1: decades and decades and of course it's still out there, right,

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Speaker 1: Pioneer ten and Pioneer eleven are still out there flying

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Speaker 1: out into the depths of space being pioneers. Of course,

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Speaker 1: now I have to admit I did not know what

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Speaker 1: the Pioneer spacecraft is or the anomaly. I was a

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Speaker 1: little puzzled by this, but as usually, we were wondering

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Speaker 1: how many of you out there no or new this

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Speaker 1: Pioneer anomaly is. So thank you to everybody who volunteered

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Speaker 1: to answer these questions. If you'd like to participate for

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Speaker 1: a future episode, please don't be shy. Right to me

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Speaker 1: two questions at Daniel and Jorge dot com. So think

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Speaker 1: about it for a second. If someone asked you what

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Speaker 1: the Pioneer anomaly is or was, what would you say.

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Speaker 1: Here's what peopled to say. I don't know, but I

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Speaker 1: imagine it's an abnormality're pretending to spacecraft or something. I'm

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Speaker 1: not totally sure what the Pioneer a normally is. Um

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Speaker 1: I can end the guest that has something to do

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Speaker 1: with the Pioneer spacecraft that were launched in the early seventies.

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Speaker 1: And I think, and now a very long why, I

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Speaker 1: have no idea. I don't know I have no idea

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Speaker 1: what the Pioneer anomaly was, but I assume it has

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Speaker 1: something to do with the Pioneer spacecraft and obviously something

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Speaker 1: that you would not normally expect to have of help them.

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Speaker 1: I think that the Pioneer anomally was maybe like this

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Speaker 1: first irregularity found about our universe, and since it's the

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Speaker 1: Pioneer anomally, I think that this maybe marked like a

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Speaker 1: turning point for scientists and made them more curious about

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Speaker 1: what other anomalies can be found in our universe. Al Right,

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Speaker 1: not a lot of name recognition here, No, I was

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Speaker 1: a little surprised. I thought this was a little more famous.

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Speaker 1: I remember hearing about this in high school and thinking, woh,

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Speaker 1: that's cool. I bet that's something real. Whoa you heard

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Speaker 1: about it in high school? Like, oh yeah, like in

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Speaker 1: physics class, or how did you hear about it from

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Speaker 1: your physics parents. I was a nerd, big shocker, so

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Speaker 1: I just kind of interested in this stuff, and you know,

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Speaker 1: anything out there in space that was unexplained, anything that

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Speaker 1: might be a clue as to how something is working

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Speaker 1: in the universe. I gobbled that stuff up to what

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Speaker 1: I heard that we didn't understand where this spacecraft was

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Speaker 1: and what it was doing, and why I was doing

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Speaker 1: these weird things I thought. I think the real anomaly

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Speaker 1: is that you used the past tense when you said

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Speaker 1: you were a nerd. It's not up to me to

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Speaker 1: evaluate that. All right, Well, there is something called the

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Speaker 1: Pioneer anomaly, and let's break it down for people. Daniel,

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Speaker 1: what is the Pioneer anomaly? So, as expected, it's an

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Speaker 1: anomoly that has to do with the Pioneer spacecraft and

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Speaker 1: specifically is that we didn't understand where it was going

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Speaker 1: and why it seemed to be going off course for

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Speaker 1: reasons we did not understand. Okay, so it was a spacecraft,

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Speaker 1: meaning like a satellite. I always get confusible to say

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Speaker 1: spacecraft because I imagine you know, Battlestar Galactica or you know,

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Speaker 1: people in uh in a cockpit or something. But really

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Speaker 1: would just mean, like, you know, any device we launched

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Speaker 1: into space is called the spacecraft. Yeah, it's not a

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Speaker 1: satellite because it's not in orbit around Earth or any

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Speaker 1: other sort of body. It's just sort of sent out

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Speaker 1: there to explore. And it's called pioneer because it really

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Speaker 1: was a pioneering mission. It was the first thing from Earth,

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Speaker 1: first scientific object sent out to explore the outer Solar System.

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Speaker 1: It was the first man made object to go through

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Speaker 1: the asteroid belt. For example, it was the first close

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Speaker 1: flyby of Jupiter, Like the first close up pictures of

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Speaker 1: Jupiter came from Pioneer. So when was it launched. It

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Speaker 1: was a while ago, right, maybe older than us. It's

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Speaker 1: been a nerd since longer than I have. Pioneer ten

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Speaker 1: was launched in March of seventy two, and Pioneer eleven

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Speaker 1: in April of seventy three. And you know, these were

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Speaker 1: iconic missions. Before this, we didn't really know what things

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Speaker 1: looked like out there. We had telescopes from Earth that

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Speaker 1: were pretty good, I guess, nothing compared to what we

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Speaker 1: have now. But if you call up in your mind

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Speaker 1: an image of Jupiter, you probably have a pretty detailed

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Speaker 1: image thanks to Hubble and thanks to all the spacecraft

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Speaker 1: we sent to visit close up. But in the seventies,

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Speaker 1: if you tried to do that, all you could have

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Speaker 1: was like a blurry smear. We just didn't know in

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Speaker 1: detail what these planets looked like until we went to

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Speaker 1: visit them. So this was the first spacecraft to go

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Speaker 1: and do that. Wow, even our telescopes couldn't get us

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Speaker 1: a good picture. I mean they were all right, but

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Speaker 1: nothing compared to what Pioneer could do. And it was

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Speaker 1: an exciting moment even for the public. When these pictures

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Speaker 1: started to come back. They had like a prime time

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Speaker 1: television show to release these to the public, and people

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Speaker 1: were glued to their screens. That TV show actually won

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Speaker 1: an Emmy. Really, they had a whole show where they

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Speaker 1: just revealed the photographs. Yeah, exactly. It was exciting. People

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Speaker 1: wanted to know, so it was really popular. It was

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Speaker 1: you know, back in the day, every sort of launch

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Speaker 1: was a special moment, and these kind of pictures they

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Speaker 1: were priceless. They still are now. Was it a daytime

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Speaker 1: Emmy or a prime time Emmy? Those are two very

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Speaker 1: different things. I think it was a prime time Emmy.

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Speaker 1: That's the good one. Right, Well, it depends on you

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Speaker 1: know what you're going for. So they launched a spacecraft

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Speaker 1: in seventy two, and they launched like a brother, like

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Speaker 1: a sibling sister spacecraft in the next year. Yeah, Pioneer

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Speaker 1: ten went to visit Jupiter and then Pioneer eleven did

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Speaker 1: Jupiter and Saturn, and this is the end of the series,

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Speaker 1: like these are ten and eleven. There was Pioneer six,

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Speaker 1: Pioneers seven, Pioneer eight, Pioneer line. Those are in sort

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Speaker 1: of solar orbit there like experimental spacecraft to develop the technology.

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Speaker 1: But these have all lasted for decades, Like we heard

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Speaker 1: from Pioneer ten last in two thousand and three, which

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Speaker 1: is like thirty years after we launched it. Wow. Now

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Speaker 1: it's kind of weird because if you're like Pioneer number thirteen,

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Speaker 1: are you still a pioneering the thirteen first want to

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Speaker 1: do something? That's true? But Pioneer tend you know, it

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Speaker 1: was the furthest object from humanity for a long time,

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Speaker 1: and it was like the farthest humans have had an

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Speaker 1: impact on the universe was Pioneer ten. More recently, we

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Speaker 1: sent Voyager one, which was launched in seventy seven and

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Speaker 1: it was going faster. So it's now the furthest object

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Speaker 1: from humanity, even though it left later. Now paint the

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Speaker 1: picture for us, what what do these spacecraft look like?

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Speaker 1: They basically look like a big satellite dish, which is

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Speaker 1: how they communicate back to us, and then there's like,

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Speaker 1: you know, a cube of electronics strap to the back

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Speaker 1: and that's where you have like instruments and you know,

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Speaker 1: things that make measurements. This one has like a cosmic

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Speaker 1: rate telescope on it, something to analyze plasma, something to

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Speaker 1: analyze radiation. And then they've got a few things sticking

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Speaker 1: off of them, like these big arms that stick off,

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Speaker 1: and that's where the power sources are. For example, these

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Speaker 1: things are powered by radiation. There's a radio isotope thermoelectric

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Speaker 1: generator's plutonium in it, and it's basically just plutonium is

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Speaker 1: decaying and that the energy from the decay turns into heat,

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Speaker 1: which then they turn into electricity, and that powers this thing.

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Speaker 1: It's like a plutonium battery. Well, it's a nuclear powered

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Speaker 1: spacecraft basically, right, Yeah, how else could you power this thing?

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Speaker 1: Solar panels wouldn't be effective after decades when you're so

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Speaker 1: far from the Sun that it just looks like another star,

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Speaker 1: and we couldn't charge up our batteries and send them

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Speaker 1: out there. So really nuclear power is the only way

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Speaker 1: to power these very very long lived spacecraft. All right.

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Speaker 1: So we sent it out, and we sent it out

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Speaker 1: to Jupiter and Saturn, and as something happened along the way,

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Speaker 1: something weird happened. Yeah, the weird thing is that it

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Speaker 1: wasn't flying the way that we thought it should. A

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Speaker 1: Pioneer turns out to be sort of unexpectedly a really

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Speaker 1: really sensitive instrument to measure gravitational pull of everything in

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Speaker 1: the Solar System, and that's because it almost never fires

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Speaker 1: its thrusters. It's just sort of like a ball we

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Speaker 1: threw out into space. A lot of the other satellites

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Speaker 1: that we send out there, like Voyager, it's got a

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Speaker 1: bunch of thrusters and it's constantly firing them to change

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Speaker 1: this direction. So it's hard to predict exactly where it

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Speaker 1: should be. A Pioneer, it's just spin stabilized, and we

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Speaker 1: just launched it out there, so we can use sort

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Speaker 1: of Newton's theory of gravity and then Einstein's modification to

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Speaker 1: predict exactly where it should be at any given moment.

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Speaker 1: And when they measure to see where it actually was,

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Speaker 1: it turns out it was kind of off course. Wait

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Speaker 1: a minute. First of all, we just threw it out there.

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Speaker 1: It doesn't have like, you know, a thrusters to steer

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Speaker 1: it or to change its direction. It does have some

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Speaker 1: small thrusters and a little bit of fuel but these

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Speaker 1: are just in case it needs, of course correction. But yeah,

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Speaker 1: unlike later, spacecraft is primarily just like a rock that

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Speaker 1: we throw out into space. Now we keep it spinning

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Speaker 1: a right that helps stabilize it to go in the

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Speaker 1: right direction. But essentially we just toss it out there

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Speaker 1: and then we just measure to see where it went,

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Speaker 1: and that tells us something about like the gravity that

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Speaker 1: experiences along the way. That's wow. And how do we

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Speaker 1: know where it is? If we just throw it out

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Speaker 1: on into space. It sends us messages and it answers messages,

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Speaker 1: and we can tell how far away it is by

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Speaker 1: how long those messages take to come back. And we

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Speaker 1: can also tell how fast it's going by the Doppler

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Speaker 1: shift of its messages. The faster it's going, the more

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Speaker 1: the wavelength is change of the messages that return. So

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Speaker 1: we have those two pieces of information, how far away

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Speaker 1: it is and how fast it's going. And I guess

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Speaker 1: we triangulate like if we've talked it one day and

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Speaker 1: then we talked it the next month, and we can

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Speaker 1: sort of as the Earth move, we can is that

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Speaker 1: how we can tell where it is? Yeah, Also because

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Speaker 1: we can tell where the signal is coming from right

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Speaker 1: and located in the sky, and so we can tell

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Speaker 1: where it is, how far way it is, and how

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Speaker 1: fast it's moving, and then we compare that to like

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Speaker 1: our model of where we think it should be. Are

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Speaker 1: you want to keep up to date and like is

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Speaker 1: this thing going in the right direction and isn't it

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Speaker 1: a crash into Jupiter or just fly by? Right? All right?

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Speaker 1: So then we threw this spacecraft into space and it

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Speaker 1: didn't go where we thought it would, right, that's the anomaly.

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Speaker 1: That's the anomaly. It was hundreds of kilometers off course.

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Speaker 1: Something was pulling on this thing. It was slowing it

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Speaker 1: down in a way that we did not understand. There's

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Speaker 1: some small acceleration of this thing towards the Sun that

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Speaker 1: didn't have an explanation from any known physics. Weird, hundreds

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Speaker 1: of kilometers off course, that's that's not a little. It's

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Speaker 1: not a little like if I if I missed an

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Speaker 1: address by kilometers of being another state. Yeah, it's actually

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Speaker 1: a really really tiny effect, but it adds up over

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Speaker 1: the thousands and thousands kilometers of its journey. The effect

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Speaker 1: of this force, this unexplained anomalous force, is ten billion

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Speaker 1: times smaller then the acceleration we feel here on Earth

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Speaker 1: from the gravitational pull of the Earth. So that's small

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Speaker 1: effect really adds up over the lifetime the decades of

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Speaker 1: this craft's flight to get it hundreds of kilometers off course,

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Speaker 1: all right, And so and we knew one thing about it,

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Speaker 1: which is that this mystery acceleration was directed towards the Sun.

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Speaker 1: That's one clue. That's one clue. The other clue was

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Speaker 1: that the same thing happened for Pioneer eleven wasn't just

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Speaker 1: like some weird thing like, oh, maybe we shot Pioneer

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Speaker 1: tan off in the wrong direction or make a mismeasurement

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Speaker 1: early on, like the same thing happened to another spacecraft.

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Speaker 1: I see, did it happen for Pioneer one through nine? Uh?

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Speaker 1: Those guys didn't go out into the outer Solar System,

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Speaker 1: so they didn't get a chance to probe that. I see.

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Speaker 1: They weren't true pioneers. Yeah, And the Voyager missions which

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Speaker 1: went out sort of in the same area, they had

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Speaker 1: lots of complicated thrusters and were always doing these adjustments,

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Speaker 1: and so they weren't nearly as precise probes of gravity.

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Speaker 1: They weren't just like pure flying rocks. All right, so

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Speaker 1: that's the Pioneer anomaly, the big mr. What was happening

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Speaker 1: to the spacecraft that was steering them off course. So

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Speaker 1: let's get into what could be possible explanations for this

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Speaker 1: effect and also how it was possibly fixed. But first

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Speaker 1: let's take a quick break. All right, we're talking about

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Speaker 1: the Pioneer anomaly. These are spacecraft we launched in the

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Speaker 1: seventies out towards Tupiter and Saturn, and they sort of

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Speaker 1: got off course for some mysterious reason. Daniel, Um. These

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Speaker 1: are spacecrafts that are still out there, right. They're gonna

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Speaker 1: be out there for a long time. They're gonna be

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Speaker 1: out there forever. They just keep going, right. There's nothing

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Speaker 1: we can do to stop them or pull them back.

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Speaker 1: They're just sort of headed out into the galaxy. They

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Speaker 1: won't run out of batteries. They will run out of

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Speaker 1: batteries eventually, you know, the half life of their plutonium

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Speaker 1: batteries like eighty seven years, So it's gonna go for

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Speaker 1: a while. But yeah, eventually it will run out of battery.

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Speaker 1: But that's not going to stop it, right, It doesn't

355
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Speaker 1: need battery to go. It just has its velocity and

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Speaker 1: it just keeps flying. Oh wow, like basically too trash

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Speaker 1: out into space. He'll be there forever. But we labeled

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Speaker 1: our trash, right, we put our names on it. We

359
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Speaker 1: said exactly who we are and what we're like found,

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Speaker 1: come conquer us and us. This is reperiment on us. Yeah,

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Speaker 1: it's commediently pointing towards us, right, yeah, exactly. And we

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Speaker 1: put a plaque on it. We said exactly how to

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Speaker 1: get to Earth. We put like a pulsar map, so

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Speaker 1: if you knew where the pulsars were in the galaxy,

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Speaker 1: you could exactly triangulate where our solar system was. We

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Speaker 1: put a picture of humans on it. We even recorded

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Speaker 1: some sounds from Earth and put it on there, as

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Speaker 1: if like they would know how to play a record

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Speaker 1: and know how to interpret that. So we threw these

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Speaker 1: spacecraft out into the outer Solar system and they started

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Speaker 1: veering off course for some mysterious reason. Now that people

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Speaker 1: freak out or were they just sort of puzzled about

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Speaker 1: this At first, they were just puzzled and they figured, well,

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Speaker 1: we must have made a mistake somewhere, or there's tiny

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Speaker 1: little effect that we hadn't accounted for, because you know,

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Speaker 1: it's not just as simple as you toss a rock

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Speaker 1: out into space and then you do gravitational calculations. There

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Speaker 1: are lots of really small effects. You know. One set

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Speaker 1: of small effects is like, well, there's a lot of

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Speaker 1: different sources of gravity. It's not just the Sun that's

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Speaker 1: pulling on these things, and it's all the planets and

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Speaker 1: all the moons and all the rocks in the asteroid

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Speaker 1: belt and all the tiny little things in the Kuiper Belt,

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Speaker 1: and you know, even other stars provide tugs. So at

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Speaker 1: first people thought, oh, we just haven't been as careful

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Speaker 1: as we needed to to sort of tie up all

387
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Speaker 1: the loose ends I see, like there could have been

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Speaker 1: like it may be passed by a big asteroid that

389
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Speaker 1: maybe pulled it off course or something. Yeah, or even

390
00:20:41,680 --> 00:20:44,840
Speaker 1: simple things like maybe we're analyzing the data wrong, you know,

391
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Speaker 1: we mismeasured it or misinterpreted this result or something like that. First,

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Speaker 1: when you see something weird in your data, that's your

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Speaker 1: assumption is that we messed up or we just weren't

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Speaker 1: thorough enough. And the cool thing about pioneers that's very

395
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Speaker 1: very precise data, and so it allows for really detailed tests,

396
00:21:00,400 --> 00:21:02,440
Speaker 1: and so you can like go through your whole list

397
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Speaker 1: of ideas for what could be affecting the flight of

398
00:21:04,840 --> 00:21:06,920
Speaker 1: this thing, add them all up, and then compare them

399
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Speaker 1: to the number. It's a really valuable way to check

400
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Speaker 1: your understanding, right because I imagine you know, like you said,

401
00:21:12,760 --> 00:21:15,760
Speaker 1: your first wish is that it's aliens. But I imagine

402
00:21:15,760 --> 00:21:17,720
Speaker 1: you're also sort of afraid a little bit, like, oh

403
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Speaker 1: my god, what if I made a mistake, Like what

404
00:21:19,920 --> 00:21:23,000
Speaker 1: if I I am totally doing this where I have

405
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Speaker 1: a typo in my formula or something. Right now, does

406
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Speaker 1: that emotion also pass through you? I'm sure it does,

407
00:21:28,040 --> 00:21:30,280
Speaker 1: you know. For those guys, you remember there was one

408
00:21:30,359 --> 00:21:33,159
Speaker 1: Martian probe that crashed because somebody typed the number in

409
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Speaker 1: in the wrong units, Like there was a European group,

410
00:21:36,280 --> 00:21:38,840
Speaker 1: an American group, and somebody put something in in pounds

411
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Speaker 1: and somebody else interpreted in kilograms and oops, and then

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Speaker 1: the whole thing crashed and burned. So yeah, mistakes do happen, absolutely, Yeah,

413
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Speaker 1: just don't work with those Americans and they're non international system.

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Speaker 1: In my personal research, there's very little opportunity for aliens

415
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Speaker 1: to affect our data. I mean, that would be pretty

416
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Speaker 1: awesome if aliens change the collisions at the LHC and

417
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Speaker 1: cause new weird stuff to happen as a way to communicate. Actually,

418
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Speaker 1: that would be a pretty cool science fiction story, right,

419
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Speaker 1: discovering aliens through particle collisions. Alien pranksters, alien physics pranksters.

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00:22:15,000 --> 00:22:19,280
Speaker 1: Exactly exactly, Aliens, if you're listening, I welcome that. Please

421
00:22:19,480 --> 00:22:21,280
Speaker 1: mess with our data. It's the large age on coliders.

422
00:22:21,280 --> 00:22:26,040
Speaker 1: Send us a message. The first physics from camm Alright, so,

423
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Speaker 1: so what were some of the things that they thought

424
00:22:28,320 --> 00:22:31,200
Speaker 1: could be happening here with the Pioneer anomaly. Well, the

425
00:22:31,240 --> 00:22:33,520
Speaker 1: first thing that comes to mind is just the location

426
00:22:33,560 --> 00:22:35,800
Speaker 1: of everything in the Solar System. So they went back,

427
00:22:35,840 --> 00:22:38,720
Speaker 1: they did a really detailed check and they thought, for example, like,

428
00:22:38,800 --> 00:22:41,400
Speaker 1: how well do we actually know the location of all

429
00:22:41,440 --> 00:22:44,960
Speaker 1: the planets, you know, Earth and Jupiter and Saturn. If

430
00:22:45,000 --> 00:22:47,440
Speaker 1: those are off by a little bit, could that explain

431
00:22:47,600 --> 00:22:50,400
Speaker 1: you know, a little gravitational tug. And you know, we

432
00:22:50,480 --> 00:22:53,160
Speaker 1: know these things really well because we've been watching these

433
00:22:53,160 --> 00:22:55,880
Speaker 1: planets for a long time and they mostly just obayue gravity.

434
00:22:56,080 --> 00:22:58,600
Speaker 1: So we have really really detailed models. We know the

435
00:22:58,600 --> 00:23:01,679
Speaker 1: location these planets down to the meter, and these effects

436
00:23:01,720 --> 00:23:04,639
Speaker 1: are just too small. So, like we think we know

437
00:23:04,960 --> 00:23:07,160
Speaker 1: the gravity from all the planets and all the little

438
00:23:07,160 --> 00:23:09,639
Speaker 1: things in the Solar system, there is uncertainly there, but

439
00:23:09,680 --> 00:23:12,480
Speaker 1: it can't explain an effect of this size, all right,

440
00:23:12,480 --> 00:23:16,159
Speaker 1: So it wasn't our measurement of the planets could be

441
00:23:16,200 --> 00:23:19,000
Speaker 1: the measurement of you know, asteroids, because there is a

442
00:23:19,000 --> 00:23:21,840
Speaker 1: lot of dark asteroids out there. There were some asteroids

443
00:23:21,840 --> 00:23:24,919
Speaker 1: out there, but those are all really small. You know. Remember,

444
00:23:24,960 --> 00:23:27,800
Speaker 1: gravity is really weak, and so to have any sort

445
00:23:27,840 --> 00:23:29,919
Speaker 1: of effect, you either have to be large or you

446
00:23:29,960 --> 00:23:32,760
Speaker 1: have to be close. So because the same thing happened

447
00:23:32,760 --> 00:23:35,040
Speaker 1: to Pioneer eleven, we didn't think it was like a

448
00:23:35,119 --> 00:23:37,879
Speaker 1: one off event that just like some object happened to

449
00:23:37,920 --> 00:23:40,399
Speaker 1: get near one of these things. So it seemed like

450
00:23:40,480 --> 00:23:42,600
Speaker 1: it had to be some sort of more systemic thing.

451
00:23:43,000 --> 00:23:45,080
Speaker 1: Another thing people thought about is like, well, what about

452
00:23:45,119 --> 00:23:48,240
Speaker 1: the solar wind? Right, the Sun is pushing on things,

453
00:23:48,320 --> 00:23:50,320
Speaker 1: It's not just tugging on them with gravity is actually

454
00:23:50,359 --> 00:23:53,480
Speaker 1: pushing on everything. You know, it's sending out streams of particles.

455
00:23:53,520 --> 00:23:55,880
Speaker 1: You could use that as a solar sales and navigate

456
00:23:55,920 --> 00:23:58,119
Speaker 1: the Solar system. So if you're like hunting down for

457
00:23:58,320 --> 00:24:01,040
Speaker 1: tiny little effects. You might want to consider the effects

458
00:24:01,040 --> 00:24:03,760
Speaker 1: of the photons and the protons and the electrons that

459
00:24:03,840 --> 00:24:06,600
Speaker 1: the Sun is streaming out right, but the solar wind

460
00:24:06,640 --> 00:24:09,600
Speaker 1: is pushing things up. But here something was kind of

461
00:24:09,640 --> 00:24:13,160
Speaker 1: pulling the spacecraft towards the Sun right exactly, So it's

462
00:24:13,160 --> 00:24:15,920
Speaker 1: the wrong direction. If anything, you would expect the solar

463
00:24:15,920 --> 00:24:18,680
Speaker 1: wind to accelerate it, to push it further out into

464
00:24:18,680 --> 00:24:21,040
Speaker 1: the Solar system, making go faster. So we needed some

465
00:24:21,119 --> 00:24:23,679
Speaker 1: other effects, something that was tugging it back into the

466
00:24:23,680 --> 00:24:26,600
Speaker 1: Solar system. And so this long list of basic checks

467
00:24:26,600 --> 00:24:29,000
Speaker 1: were done, and none of them could explain what was

468
00:24:29,040 --> 00:24:31,760
Speaker 1: going on. None of them are sort of strong enough

469
00:24:31,800 --> 00:24:35,400
Speaker 1: to account for the deviations of hundreds of kilometers, So

470
00:24:35,480 --> 00:24:38,080
Speaker 1: it wasn't the basic stuff. Then that's when people started

471
00:24:38,080 --> 00:24:40,960
Speaker 1: to get creative. I imagine, Yeah, they started to get creative.

472
00:24:40,960 --> 00:24:43,840
Speaker 1: They thought, well, what if there's something else on the

473
00:24:43,880 --> 00:24:47,040
Speaker 1: spacecraft that's basically giving it a little push. You know

474
00:24:47,040 --> 00:24:50,000
Speaker 1: what if there's like effectively a thruster, Because think about

475
00:24:50,000 --> 00:24:53,320
Speaker 1: the batteries on these spacecraft. These things generate heat, and

476
00:24:53,359 --> 00:24:56,479
Speaker 1: things that are hot radiate photons, and when you radiate

477
00:24:56,480 --> 00:25:00,440
Speaker 1: a photon, you're basically getting pushed. You know, you shoot

478
00:25:00,440 --> 00:25:03,200
Speaker 1: off a photon to the left, then by conservation momentum,

479
00:25:03,280 --> 00:25:06,560
Speaker 1: you're going to the right, and everybody, everything that is

480
00:25:06,640 --> 00:25:09,800
Speaker 1: hot is giving off photons. Like me and you, we

481
00:25:09,960 --> 00:25:12,119
Speaker 1: glow in the infrared. Right, you put on night vision

482
00:25:12,119 --> 00:25:15,200
Speaker 1: goggles like the Predator, you can see a human body

483
00:25:15,280 --> 00:25:17,920
Speaker 1: because it's giving off in for a red photon. I

484
00:25:17,960 --> 00:25:22,560
Speaker 1: knew you would work in aliens somehow. Wait does that mean?

485
00:25:22,600 --> 00:25:25,639
Speaker 1: Like if I put a flashlight out into space and

486
00:25:25,680 --> 00:25:28,119
Speaker 1: turn it on, it would start to go like it

487
00:25:28,119 --> 00:25:31,000
Speaker 1: would basically act like a rocket. Yes, a flashlight is

488
00:25:31,000 --> 00:25:34,480
Speaker 1: a rocket, absolutely. It throws particles out the back, and

489
00:25:34,520 --> 00:25:37,000
Speaker 1: so it has to go the other direction. Now, if

490
00:25:37,000 --> 00:25:39,840
Speaker 1: you put two flashlights shining in the opposite directions, it

491
00:25:39,880 --> 00:25:42,879
Speaker 1: won't go anywhere. They'll balance each other. So the pioneer

492
00:25:43,000 --> 00:25:45,280
Speaker 1: people thought, well, it's got these things on it, but

493
00:25:45,320 --> 00:25:48,320
Speaker 1: they glow in every direction, right, and so if heat

494
00:25:48,400 --> 00:25:50,399
Speaker 1: is the same everywhere in the spacecraft, that's not going

495
00:25:50,440 --> 00:25:53,040
Speaker 1: to effectively give it a push. When did? It depends

496
00:25:53,040 --> 00:25:55,119
Speaker 1: on the shape, Like a hot sphere would give up

497
00:25:55,200 --> 00:25:58,040
Speaker 1: photons in all directions, But maybe, like I don't know,

498
00:25:58,080 --> 00:26:00,280
Speaker 1: like it's something it looks like a dish might not. No,

499
00:26:00,400 --> 00:26:02,680
Speaker 1: you're right, and it's a really interesting clue. And people

500
00:26:02,720 --> 00:26:05,280
Speaker 1: thought for a while about this, like maybe the complicated

501
00:26:05,280 --> 00:26:07,919
Speaker 1: shape of the spacecraft is not giving off heat in

502
00:26:07,920 --> 00:26:11,480
Speaker 1: the same direction everywhere. But there was another important clue,

503
00:26:11,520 --> 00:26:14,280
Speaker 1: which was that this effect wasn't dropping as a function

504
00:26:14,320 --> 00:26:16,800
Speaker 1: of time, like it wasn't fading. And we know the

505
00:26:16,800 --> 00:26:19,679
Speaker 1: heat from these batteries should be fading, like this is

506
00:26:19,680 --> 00:26:22,960
Speaker 1: a radioactive thing. It decays over the half life of

507
00:26:22,960 --> 00:26:25,760
Speaker 1: eighty seven years. These things eventually cool and then just

508
00:26:25,840 --> 00:26:28,880
Speaker 1: become dead. And so if it's due to the heat

509
00:26:28,920 --> 00:26:30,919
Speaker 1: of the batteries, you would expect this thing to fade

510
00:26:31,000 --> 00:26:33,399
Speaker 1: with time. But the data we had showed that it

511
00:26:33,440 --> 00:26:36,359
Speaker 1: was constant. So people thought, well, can't be the batteries.

512
00:26:36,840 --> 00:26:40,280
Speaker 1: I see, it wasn't cool enough. It wasn't getting cool alright,

513
00:26:40,320 --> 00:26:42,640
Speaker 1: So then what else did did they think it could be?

514
00:26:42,720 --> 00:26:45,239
Speaker 1: So that's when he got exciting. They thought, well, we

515
00:26:45,320 --> 00:26:48,680
Speaker 1: can't explain this using any sort of known physics, any

516
00:26:48,720 --> 00:26:51,679
Speaker 1: solar wind or any gravity or any heating of the spacecraft,

517
00:26:51,720 --> 00:26:55,160
Speaker 1: so let's get creative. And people thought, well, maybe we've

518
00:26:55,280 --> 00:26:59,920
Speaker 1: accidentally created something which measures like the expansion of the universe,

519
00:27:00,200 --> 00:27:04,320
Speaker 1: because they thought maybe space is expanding inside the Solar

520
00:27:04,359 --> 00:27:08,159
Speaker 1: System and it creates this weird gravitational potential. And we

521
00:27:08,200 --> 00:27:12,400
Speaker 1: know that gravity and time are connected because, for example,

522
00:27:12,680 --> 00:27:16,160
Speaker 1: if you go near a black hole, time slows down

523
00:27:16,200 --> 00:27:21,359
Speaker 1: for you. So over vast stretches of space, potentially time

524
00:27:21,440 --> 00:27:24,119
Speaker 1: is getting slowed down as you move through these like

525
00:27:24,320 --> 00:27:28,439
Speaker 1: expanded space. Whereas our clocks, the ones that we're using

526
00:27:28,720 --> 00:27:31,280
Speaker 1: to sort of predict where this thing goes, these really

527
00:27:31,320 --> 00:27:35,640
Speaker 1: precise atomic clocks basically assume that space is flat. So

528
00:27:35,680 --> 00:27:39,240
Speaker 1: if we're measuring time differently than something that's flying out

529
00:27:39,280 --> 00:27:42,359
Speaker 1: into the Solar System, then maybe that could explain it,

530
00:27:43,400 --> 00:27:47,040
Speaker 1: meaning like maybe the clock on the spacecraft is wrong

531
00:27:47,400 --> 00:27:49,560
Speaker 1: or do you mean like it's actually in a different time,

532
00:27:49,880 --> 00:27:52,880
Speaker 1: it's actually in a different time. Yeah, this falls under

533
00:27:52,880 --> 00:27:56,760
Speaker 1: this whole set of ideas like the non uniformity of time, right,

534
00:27:56,800 --> 00:27:58,520
Speaker 1: And we've talked a lot in the podcast about how

535
00:27:58,560 --> 00:28:01,639
Speaker 1: my clock and your clock can disagree but both be

536
00:28:01,760 --> 00:28:05,560
Speaker 1: correct because there is no universal sense of time. So

537
00:28:05,600 --> 00:28:08,160
Speaker 1: this is an idea sort of along that direction, like

538
00:28:08,560 --> 00:28:11,720
Speaker 1: maybe we're measuring the expansion of space and those gravitational

539
00:28:11,760 --> 00:28:14,760
Speaker 1: effects are distorting the clock on the spacecraft, not that

540
00:28:14,800 --> 00:28:17,640
Speaker 1: it's wrong, but you know it's different. It's just differently timed.

541
00:28:17,880 --> 00:28:19,919
Speaker 1: I see. So maybe the idea is that maybe it

542
00:28:20,080 --> 00:28:22,720
Speaker 1: is it was supposed to be, but our measurement of

543
00:28:22,720 --> 00:28:26,359
Speaker 1: where it is is wrong because the timing in the

544
00:28:26,400 --> 00:28:29,480
Speaker 1: clock on board is different than it we think it

545
00:28:29,520 --> 00:28:32,280
Speaker 1: should be. And that was so the general concept like

546
00:28:32,359 --> 00:28:34,840
Speaker 1: maybe something in this direction will help us because we

547
00:28:34,880 --> 00:28:37,520
Speaker 1: know gravity and time are connected. But they couldn't actually

548
00:28:37,560 --> 00:28:39,840
Speaker 1: make it work. They try to get the map all

549
00:28:39,880 --> 00:28:42,720
Speaker 1: work out and say, is this consistent with general relativity?

550
00:28:42,840 --> 00:28:44,840
Speaker 1: What we know about the expansion in the universe? Would

551
00:28:44,840 --> 00:28:47,520
Speaker 1: that explain that? And it could never be made consistent,

552
00:28:47,960 --> 00:28:50,080
Speaker 1: and so it would have to be like some weird

553
00:28:50,160 --> 00:28:53,520
Speaker 1: deviation have to be some special case of how times

554
00:28:53,560 --> 00:28:56,959
Speaker 1: affected by gravity for some reason only in our solar system.

555
00:28:57,280 --> 00:28:58,840
Speaker 1: And so you know, when you start to develop like

556
00:28:58,920 --> 00:29:01,560
Speaker 1: a new idea of for how to explain some weird science,

557
00:29:01,760 --> 00:29:04,160
Speaker 1: you want as simple a new idea as possible. You

558
00:29:04,200 --> 00:29:05,640
Speaker 1: don't want to have to like add all sorts of

559
00:29:05,680 --> 00:29:08,719
Speaker 1: weird bells and whistles and exceptions and stuff. And so

560
00:29:08,760 --> 00:29:11,000
Speaker 1: this started off sort of promising and then ended up

561
00:29:11,040 --> 00:29:13,920
Speaker 1: being like, it doesn't really fit. It wasn't just that

562
00:29:14,000 --> 00:29:17,400
Speaker 1: they it was in the wrong time zone or daylight savings.

563
00:29:17,840 --> 00:29:21,080
Speaker 1: That couldn't explain it either. No, I mean I make

564
00:29:21,120 --> 00:29:23,960
Speaker 1: that mistake all the time, and they usually blame it

565
00:29:23,960 --> 00:29:25,920
Speaker 1: on aliens, which is why I miss a meeting. But no,

566
00:29:26,440 --> 00:29:29,400
Speaker 1: they couldn't explain this using any sort of general relativistic

567
00:29:29,480 --> 00:29:33,520
Speaker 1: effects on the clock or even simple modifications to general

568
00:29:33,560 --> 00:29:36,040
Speaker 1: relativity to allow for effects on the clock of the

569
00:29:36,080 --> 00:29:39,400
Speaker 1: expanding space in the Solar System. So that didn't work out.

570
00:29:39,680 --> 00:29:43,560
Speaker 1: You can't blame the engineers, and you can't blame Einstein

571
00:29:43,720 --> 00:29:47,640
Speaker 1: or general relativity. What else could it have been. Well,

572
00:29:47,640 --> 00:29:49,640
Speaker 1: people got excited for a while when they thought maybe

573
00:29:49,680 --> 00:29:53,400
Speaker 1: it was dark matter. Right, we've accounted for the gravitational

574
00:29:53,480 --> 00:29:56,560
Speaker 1: sources that we know about the planets and the rocks

575
00:29:56,600 --> 00:29:59,080
Speaker 1: and the Sun, But we also know that most of

576
00:29:59,120 --> 00:30:01,640
Speaker 1: the gravity in the Unit verse isn't from the stuff

577
00:30:01,680 --> 00:30:05,160
Speaker 1: that we can see. It's actually from this weird invisible matter.

578
00:30:05,280 --> 00:30:08,840
Speaker 1: We still won't understand that's everywhere, and we think that

579
00:30:08,920 --> 00:30:12,160
Speaker 1: it fills the galaxy. In fact extends beyond the galaxy

580
00:30:12,200 --> 00:30:14,520
Speaker 1: and it's five times as much of it as there

581
00:30:14,600 --> 00:30:18,520
Speaker 1: is normal matters. So if you're studying details of gravitational effects,

582
00:30:18,600 --> 00:30:20,800
Speaker 1: you might expect to have to take into account the

583
00:30:20,880 --> 00:30:24,160
Speaker 1: dark matter. Interesting. Yeah, like our solar system could be

584
00:30:24,360 --> 00:30:27,800
Speaker 1: or is probably bated in dark matter, right, that could

585
00:30:27,960 --> 00:30:31,880
Speaker 1: potentially affect the gravity of things we send out into space. Absolutely,

586
00:30:31,960 --> 00:30:35,040
Speaker 1: dark matter definitely is here. It's everywhere. It's all around us.

587
00:30:35,080 --> 00:30:37,640
Speaker 1: There's dark matter with us in this room, the dark

588
00:30:37,680 --> 00:30:40,240
Speaker 1: matter all around the Earth. We can't see it or

589
00:30:40,280 --> 00:30:43,320
Speaker 1: detective because we think it only has a gravitational interaction.

590
00:30:43,320 --> 00:30:46,880
Speaker 1: And remember gravity is super duper weak, so usually we're

591
00:30:46,880 --> 00:30:49,520
Speaker 1: only sensitive to dark matter if there are huge amounts

592
00:30:49,520 --> 00:30:52,440
Speaker 1: of it, you know, like galaxy sized amounts to affect

593
00:30:52,440 --> 00:30:55,200
Speaker 1: how the galaxy spins. It's really hard to detect like

594
00:30:55,360 --> 00:30:58,160
Speaker 1: local blobs of dark matter. So people got excited when

595
00:30:58,160 --> 00:31:01,000
Speaker 1: they thought maybe Pioneer ten and eleven are like a

596
00:31:01,040 --> 00:31:03,640
Speaker 1: local prob they're telling us how much dark matter there

597
00:31:03,760 --> 00:31:06,920
Speaker 1: is here. Interesting, But wouldn't if there was some anomaly

598
00:31:06,920 --> 00:31:10,920
Speaker 1: in dark matter, wouldn't it affect all the other planets too? Yeah, exactly,

599
00:31:10,920 --> 00:31:13,760
Speaker 1: it would. And we also don't think that there is

600
00:31:13,880 --> 00:31:16,760
Speaker 1: that much dark matter. We know that there's five times

601
00:31:16,760 --> 00:31:19,280
Speaker 1: as much dark matter in general in the universe, but

602
00:31:19,360 --> 00:31:22,000
Speaker 1: we don't think in our Solar System there's that much

603
00:31:22,280 --> 00:31:25,360
Speaker 1: because doesn't clump up we think the way normal matter does.

604
00:31:25,720 --> 00:31:27,760
Speaker 1: Like if you took the normal matter in the galaxy

605
00:31:27,760 --> 00:31:30,160
Speaker 1: and just spread it out throughout the whole volume of

606
00:31:30,160 --> 00:31:32,560
Speaker 1: the galaxy, it would be pretty thin. That's the way

607
00:31:32,640 --> 00:31:34,520
Speaker 1: dark matter is. There's five times as much of it,

608
00:31:34,680 --> 00:31:37,239
Speaker 1: but it's much more spread out than normal matter is.

609
00:31:37,600 --> 00:31:40,680
Speaker 1: So sort of in the volume of the Solar System,

610
00:31:41,080 --> 00:31:44,160
Speaker 1: it's like one million of the mass of the Sun

611
00:31:44,760 --> 00:31:47,400
Speaker 1: of dark matter, right, see, So it couldn't be that either.

612
00:31:47,800 --> 00:31:50,360
Speaker 1: So then they couldn't blame it on a technical issue

613
00:31:50,640 --> 00:31:53,800
Speaker 1: or sort of a theoretical issue, And so it was

614
00:31:53,920 --> 00:31:56,800
Speaker 1: a big mystery, I mean for decades, right, Like they've

615
00:31:56,800 --> 00:32:01,000
Speaker 1: seen this anomaly for you know, a thirty almost forty years. Yeah,

616
00:32:01,040 --> 00:32:02,960
Speaker 1: people really worked on it for a long time, and

617
00:32:02,960 --> 00:32:04,920
Speaker 1: it was in the nineties of people that is really

618
00:32:05,000 --> 00:32:09,880
Speaker 1: detailed investigation went through all these possible explanations and couldn't

619
00:32:09,920 --> 00:32:11,760
Speaker 1: explain it, And then people had a lot of fun

620
00:32:11,880 --> 00:32:14,440
Speaker 1: coming up with theories of new physics to try to

621
00:32:14,480 --> 00:32:17,080
Speaker 1: explain it potentially, and it's sort of like a standing

622
00:32:17,240 --> 00:32:20,200
Speaker 1: question in science for quite a while. People even try

623
00:32:20,240 --> 00:32:24,200
Speaker 1: to explain it using like weird modified gravity, like maybe

624
00:32:24,240 --> 00:32:27,280
Speaker 1: gravity doesn't work the way Einstein and Newton thought we did,

625
00:32:27,320 --> 00:32:29,920
Speaker 1: and somehow gravity changes when you get out into the

626
00:32:29,920 --> 00:32:32,520
Speaker 1: outer Solar system. But you know, that doesn't really make

627
00:32:32,560 --> 00:32:36,480
Speaker 1: sense because we understand how Pluto and Neptune and Neurinus operate.

628
00:32:36,680 --> 00:32:39,400
Speaker 1: So there are a lot of questions about what could

629
00:32:39,400 --> 00:32:42,080
Speaker 1: explain this on a lot of crazy ideas thought up

630
00:32:42,160 --> 00:32:44,440
Speaker 1: to explain it, none of which were ever really very

631
00:32:44,480 --> 00:32:47,080
Speaker 1: compelling or which worked. So it's sort of a question like,

632
00:32:47,200 --> 00:32:50,120
Speaker 1: are we gonna find some boring explanation for what this is?

633
00:32:50,480 --> 00:32:52,000
Speaker 1: Or is somebody going to come up with a new

634
00:32:52,080 --> 00:32:54,360
Speaker 1: idea that actually, you know, makes it all click together

635
00:32:54,600 --> 00:32:57,480
Speaker 1: and tells us something new and deep about the universe? Right?

636
00:32:57,520 --> 00:32:59,240
Speaker 1: Are you going to get a try again when you

637
00:32:59,240 --> 00:33:01,600
Speaker 1: scratch out the start of it? Or are you gonna

638
00:33:00,920 --> 00:33:04,600
Speaker 1: win a million aliens in the process. All right, Well,

639
00:33:04,720 --> 00:33:08,040
Speaker 1: let's get into how this mystery was finally resolved, if

640
00:33:08,040 --> 00:33:11,040
Speaker 1: it was resolved at all. But first let's take a

641
00:33:11,080 --> 00:33:28,960
Speaker 1: quick break. All right, So the Pioneer anomaly was a

642
00:33:28,960 --> 00:33:32,640
Speaker 1: big mystery for decades back in the seventies, eighties, and nineties,

643
00:33:32,840 --> 00:33:36,920
Speaker 1: spacecraft we throughout their into space. We're veering off course, Daniel,

644
00:33:36,960 --> 00:33:39,400
Speaker 1: How was it all resolved in the end. If it

645
00:33:39,560 --> 00:33:42,200
Speaker 1: was so, we actually do think we have a pretty

646
00:33:42,200 --> 00:33:44,920
Speaker 1: good understanding of what happened by now, and it's due

647
00:33:44,960 --> 00:33:48,960
Speaker 1: to some sort of like data archaeology by some researchers

648
00:33:49,000 --> 00:33:52,560
Speaker 1: really dedicated, really interested in understanding how this worked. They

649
00:33:52,560 --> 00:33:54,240
Speaker 1: went and found some old data in the mid two

650
00:33:54,320 --> 00:33:57,560
Speaker 1: thousand's and did a really detailed study and they think

651
00:33:57,600 --> 00:34:00,920
Speaker 1: they've cracked it. Oh wow, in the mid to of thousands.

652
00:34:00,920 --> 00:34:03,880
Speaker 1: So all this time, since the seventies, these space crafts

653
00:34:03,920 --> 00:34:06,360
Speaker 1: were out there off course and people just sort of

654
00:34:06,360 --> 00:34:08,040
Speaker 1: shrugged it off for a while, or that they just

655
00:34:08,080 --> 00:34:10,080
Speaker 1: gave up, or or what. Well, you know, when there

656
00:34:10,080 --> 00:34:13,120
Speaker 1: are these puzzles in science, it's not always easy to

657
00:34:13,160 --> 00:34:15,799
Speaker 1: know how to crack them, and so sometimes they'll be

658
00:34:15,800 --> 00:34:18,799
Speaker 1: out there for a long time, decades even people like,

659
00:34:18,880 --> 00:34:21,400
Speaker 1: well that's not understood, but nobody really knows what to

660
00:34:21,440 --> 00:34:24,200
Speaker 1: do about it. So finally somebody said, well, I'm gonna

661
00:34:24,200 --> 00:34:27,040
Speaker 1: try to go back and find some more data, dig

662
00:34:27,040 --> 00:34:29,520
Speaker 1: out some mold data nobody's ever seen before, and make

663
00:34:29,560 --> 00:34:32,359
Speaker 1: a more detailed study than anybody's ever done before, and

664
00:34:32,400 --> 00:34:35,319
Speaker 1: maybe we'll figure it out. Wow, that's wild to me, Like,

665
00:34:35,360 --> 00:34:37,359
Speaker 1: how do you sleep at night? Like, let's say you're

666
00:34:37,400 --> 00:34:39,640
Speaker 1: the scientists or the engineer who worked on this, Like,

667
00:34:39,800 --> 00:34:41,920
Speaker 1: how do you ever be at peace? You know, It's

668
00:34:41,920 --> 00:34:44,000
Speaker 1: like if somebody told you, hey, I know it's your

669
00:34:44,040 --> 00:34:48,160
Speaker 1: car mysteriously moves an inch every night, and you're like, well,

670
00:34:48,200 --> 00:34:51,040
Speaker 1: I don't know, how could you get to sleep? I

671
00:34:51,080 --> 00:34:53,840
Speaker 1: think that's why smart scientists have great ideas in the

672
00:34:53,880 --> 00:34:56,400
Speaker 1: middle of the night, because their brains are always working

673
00:34:56,440 --> 00:34:59,120
Speaker 1: on these things, are always chewing away on these puzzles

674
00:34:59,120 --> 00:35:03,000
Speaker 1: and these questions. All right. So then in the two thousands, UM,

675
00:35:03,040 --> 00:35:05,080
Speaker 1: a group of people said, hey, we want to figure

676
00:35:05,080 --> 00:35:08,040
Speaker 1: this out. So they say, sort of dug through all

677
00:35:08,040 --> 00:35:09,960
Speaker 1: the old data. But that was kind of hard, right,

678
00:35:10,000 --> 00:35:12,880
Speaker 1: because this is data from the seventies. Yeah, they literally

679
00:35:13,000 --> 00:35:16,400
Speaker 1: dug through old data and they were specifically focused on

680
00:35:16,440 --> 00:35:19,600
Speaker 1: this question of the heat from the batteries and whether

681
00:35:19,680 --> 00:35:22,880
Speaker 1: or not it really was decaying over time. And what

682
00:35:22,960 --> 00:35:25,640
Speaker 1: they discovered is that we didn't actually have all the data.

683
00:35:25,880 --> 00:35:28,759
Speaker 1: Some of the earliest data from the spacecraft was like

684
00:35:28,840 --> 00:35:32,040
Speaker 1: stored on magnetic tapes and not really included in most

685
00:35:32,120 --> 00:35:33,920
Speaker 1: later analyzes because it was kind of a pain to

686
00:35:33,960 --> 00:35:36,520
Speaker 1: go and find it and recover it and process it

687
00:35:36,560 --> 00:35:39,000
Speaker 1: and stuff. So they did a bit of like archaeology,

688
00:35:39,239 --> 00:35:41,960
Speaker 1: and they found more than a dozen boxes of magnetic

689
00:35:42,000 --> 00:35:46,640
Speaker 1: tapes stored under a staircase at JPL in Pasadena, and

690
00:35:46,680 --> 00:35:49,600
Speaker 1: they worked with like an old school programmer to create

691
00:35:49,640 --> 00:35:51,960
Speaker 1: software that could read these tapes and clean it up.

692
00:35:52,200 --> 00:35:55,160
Speaker 1: So they got sort of a longer time series on

693
00:35:55,320 --> 00:35:58,440
Speaker 1: the data than anybody else had, like data on what

694
00:35:58,680 --> 00:36:00,839
Speaker 1: the position of it, or like the signals we were

695
00:36:00,840 --> 00:36:03,200
Speaker 1: getting from it, or what on the position of it is,

696
00:36:03,280 --> 00:36:07,000
Speaker 1: specifically the earlier positions. Remember we talked about how we

697
00:36:07,120 --> 00:36:09,839
Speaker 1: didn't think it was just heat coming off the spacecraft

698
00:36:09,920 --> 00:36:13,759
Speaker 1: unevenly because it would have faded with time, and it

699
00:36:13,760 --> 00:36:15,719
Speaker 1: didn't look like it was fading with time. So to

700
00:36:15,760 --> 00:36:17,799
Speaker 1: trying to answer that question in more detail, they said, well,

701
00:36:17,880 --> 00:36:20,239
Speaker 1: let's look at earlier data data when it had just

702
00:36:20,400 --> 00:36:22,120
Speaker 1: left the Earth to see if we can spot this

703
00:36:22,160 --> 00:36:26,280
Speaker 1: effect earlier on. I see, you're looking for a weird

704
00:36:26,320 --> 00:36:28,799
Speaker 1: effect on where you think it should be different from

705
00:36:28,840 --> 00:36:32,359
Speaker 1: when then we're where it is, right, yeah, exactly. So

706
00:36:32,360 --> 00:36:35,080
Speaker 1: you're you're basically comparing curves. Right, you have the curve

707
00:36:35,080 --> 00:36:36,880
Speaker 1: of what you expect and the curve of where it

708
00:36:36,920 --> 00:36:38,840
Speaker 1: actually was. And now you're trying to come up with

709
00:36:39,040 --> 00:36:42,360
Speaker 1: a new expectation, like can we tweak how we understand

710
00:36:42,400 --> 00:36:45,120
Speaker 1: this thing flies so that what we expect matches what

711
00:36:45,280 --> 00:36:47,239
Speaker 1: we observe. And you also have to sort of look

712
00:36:47,280 --> 00:36:49,759
Speaker 1: back in time in the Solar system, right, like in

713
00:36:49,800 --> 00:36:52,560
Speaker 1: this back then, what where were all the planets and

714
00:36:52,600 --> 00:36:55,359
Speaker 1: asteroids and all that in order to think about where

715
00:36:55,360 --> 00:36:58,440
Speaker 1: it should have been exactly. It's a complicated calculation, and

716
00:36:58,520 --> 00:37:00,920
Speaker 1: to do this right you need to know not just

717
00:37:01,000 --> 00:37:02,839
Speaker 1: where it was, but you also need to know, as

718
00:37:02,880 --> 00:37:05,839
Speaker 1: you were saying, where it's giving off heat. Like the

719
00:37:05,840 --> 00:37:09,560
Speaker 1: shape of this thing really affects how it glows, because,

720
00:37:09,600 --> 00:37:12,399
Speaker 1: as we're talking about before, it's not just a sphere, right.

721
00:37:12,600 --> 00:37:14,920
Speaker 1: Physicists always like to assume everything is a spear at

722
00:37:14,960 --> 00:37:18,000
Speaker 1: first order, but the details matter when you're making really

723
00:37:18,080 --> 00:37:22,320
Speaker 1: really precise measurements. And this thing has two big hot

724
00:37:22,360 --> 00:37:25,240
Speaker 1: batteries on one side, and then like a cool dish

725
00:37:25,280 --> 00:37:27,319
Speaker 1: on the other side. But it also has a bunch

726
00:37:27,320 --> 00:37:30,120
Speaker 1: of instruments that use that electricity, and so as they

727
00:37:30,200 --> 00:37:32,440
Speaker 1: draw current, they get hot, and as the heat up,

728
00:37:32,480 --> 00:37:35,239
Speaker 1: they glow, and these kind of effects. Is just the

729
00:37:35,280 --> 00:37:37,800
Speaker 1: glowing heat from these things is big enough to explain

730
00:37:37,840 --> 00:37:40,160
Speaker 1: the effect that we're seeing. Yeah, and I think you know,

731
00:37:40,239 --> 00:37:42,560
Speaker 1: you say batteries and that makes me think of, you know,

732
00:37:42,680 --> 00:37:46,439
Speaker 1: like as a battery or a car battery. But really

733
00:37:46,440 --> 00:37:50,960
Speaker 1: these are like nuclear reactors right there their generators, Yeah, exactly,

734
00:37:50,960 --> 00:37:53,200
Speaker 1: they're not fission or fusion. They're just sort of like

735
00:37:53,280 --> 00:37:57,160
Speaker 1: slow rolling radioactive to k that generates the electricity. But yeah,

736
00:37:57,200 --> 00:37:59,960
Speaker 1: they are nuclear reactors. But also everything on the space

737
00:38:00,000 --> 00:38:03,080
Speaker 1: scrapt that he uses that electricity eventually leaks some of

738
00:38:03,080 --> 00:38:05,840
Speaker 1: that energy. Nothing is perfect, right, and it leaks that

739
00:38:05,960 --> 00:38:08,400
Speaker 1: energy into heat, just the same way everything that you

740
00:38:08,520 --> 00:38:10,960
Speaker 1: use as electronics in it will eventually heat up. Your

741
00:38:10,960 --> 00:38:13,440
Speaker 1: computer heats up as you use it. Right, there's no

742
00:38:13,600 --> 00:38:17,200
Speaker 1: like fire burning inside your computer. It's just inefficiency from

743
00:38:17,200 --> 00:38:19,880
Speaker 1: the use of electricity. So if you have an object

744
00:38:19,880 --> 00:38:23,239
Speaker 1: on a spacecraft that's drawing electricity, not even just the batteries,

745
00:38:23,280 --> 00:38:26,040
Speaker 1: but the equipment on the spacecraft gets hot as it

746
00:38:26,160 --> 00:38:29,240
Speaker 1: uses the electricity. To understand the effect of all this stuff,

747
00:38:29,280 --> 00:38:32,000
Speaker 1: you need to know like exactly where everything was on

748
00:38:32,040 --> 00:38:35,239
Speaker 1: the spacecraft and how hot it got. These days, we

749
00:38:35,280 --> 00:38:37,320
Speaker 1: can do that pretty well. We have like really fancy

750
00:38:37,320 --> 00:38:40,279
Speaker 1: software to model this kind of stuff, but you know,

751
00:38:40,360 --> 00:38:43,879
Speaker 1: we don't have the records that match that software from

752
00:38:43,880 --> 00:38:46,480
Speaker 1: a really really old instrument, Like this thing was built

753
00:38:46,520 --> 00:38:49,840
Speaker 1: forty years ago. You know, we have like blue plants

754
00:38:50,080 --> 00:38:54,440
Speaker 1: drawn by hand by the original designers. So these researchers

755
00:38:54,440 --> 00:38:56,640
Speaker 1: had to go in and build a model of the

756
00:38:56,640 --> 00:39:01,200
Speaker 1: sort of heat flow of Pioneer spacecraft by hand like later.

757
00:39:01,840 --> 00:39:06,120
Speaker 1: And it's involved like fifteen thousand individual pieces like exactly

758
00:39:06,200 --> 00:39:09,000
Speaker 1: where this cable goes and exactly how thick that piece

759
00:39:09,000 --> 00:39:12,680
Speaker 1: of aluminum it was, and like this is a huge effort. Wow.

760
00:39:12,880 --> 00:39:15,560
Speaker 1: So yeah, they had to basically create a virtual model

761
00:39:15,640 --> 00:39:18,760
Speaker 1: of the spacecraft and then put it out into space

762
00:39:18,800 --> 00:39:21,760
Speaker 1: with the heat source and see if it would deviate

763
00:39:21,800 --> 00:39:23,920
Speaker 1: the way that we they were seeing in the data.

764
00:39:24,160 --> 00:39:26,560
Speaker 1: It's really incredible precision. You know. Think about like when

765
00:39:26,600 --> 00:39:28,880
Speaker 1: you drive your car, do you expect your car to

766
00:39:28,920 --> 00:39:31,120
Speaker 1: slow down when you turn the headlights on right. You

767
00:39:31,160 --> 00:39:34,080
Speaker 1: don't expect it to, but actually it does. Right. Turning

768
00:39:34,120 --> 00:39:37,320
Speaker 1: on the headlights slows down your car because you're basically

769
00:39:37,320 --> 00:39:40,560
Speaker 1: shooting photons away from your car. So this is the

770
00:39:40,680 --> 00:39:43,560
Speaker 1: kind of effect that we're looking for. It's amazing that

771
00:39:43,680 --> 00:39:46,160
Speaker 1: it actually happens and they were able to figure it out.

772
00:39:46,280 --> 00:39:50,120
Speaker 1: So now they're calculations, which include more time information and

773
00:39:50,239 --> 00:39:53,959
Speaker 1: a much more detailed model of the spacecraft actually match

774
00:39:54,080 --> 00:39:57,920
Speaker 1: really well what we see. So they think they solved

775
00:39:57,920 --> 00:40:00,359
Speaker 1: the mystery. They think they've solved the mystery. Turns out

776
00:40:00,360 --> 00:40:03,480
Speaker 1: it was the plutonium in the power source next to

777
00:40:03,520 --> 00:40:08,280
Speaker 1: Saturn exactly. It's just uneven heating right eventually over many years.

778
00:40:08,440 --> 00:40:10,480
Speaker 1: The fact that one side of this thing is hotter

779
00:40:10,560 --> 00:40:13,239
Speaker 1: than the other means that it gave off more photons,

780
00:40:13,280 --> 00:40:15,160
Speaker 1: which gave it a little bit of a push. It's

781
00:40:15,160 --> 00:40:17,600
Speaker 1: like if you had two flashlights out in space and

782
00:40:17,600 --> 00:40:19,799
Speaker 1: one of them was a teensy bit brighter than the

783
00:40:19,840 --> 00:40:23,320
Speaker 1: other one, you would get pushed away from that flashlight,

784
00:40:23,600 --> 00:40:27,040
Speaker 1: tiny little bit. And that explains why it was being

785
00:40:27,040 --> 00:40:30,919
Speaker 1: pulled towards the Sun. Because you know that the way

786
00:40:31,000 --> 00:40:33,920
Speaker 1: this basecraft is designed, you know you always want to

787
00:40:33,920 --> 00:40:36,680
Speaker 1: point the dish back towards Earth kind of right, And

788
00:40:36,760 --> 00:40:39,680
Speaker 1: so that means that the hot stuff is sort of

789
00:40:39,760 --> 00:40:42,879
Speaker 1: in front of you, which was slowing it down. M Yeah,

790
00:40:42,880 --> 00:40:45,040
Speaker 1: we're pointing the hot bits of this thing out towards

791
00:40:45,120 --> 00:40:48,239
Speaker 1: the Aliens and the cold side back towards Earth. So yeah,

792
00:40:48,239 --> 00:40:50,680
Speaker 1: that effectively slows it down a tiny little bit. I

793
00:40:50,719 --> 00:40:52,680
Speaker 1: guess the lesson is, you know, it's always better to

794
00:40:52,680 --> 00:40:55,719
Speaker 1: have a hot back end. I'm not going to touch

795
00:40:55,800 --> 00:40:58,720
Speaker 1: that at all, but Pioneer eleven apparently had the same

796
00:40:58,800 --> 00:41:01,160
Speaker 1: hot back end, and that's why the same thing happened

797
00:41:01,160 --> 00:41:04,520
Speaker 1: to Pioneer eleven. The story all sort of fits together

798
00:41:04,560 --> 00:41:06,880
Speaker 1: and makes sense. And I love these sort of science

799
00:41:06,880 --> 00:41:10,080
Speaker 1: stories when it all this clicks together and the explanation

800
00:41:10,160 --> 00:41:12,760
Speaker 1: matches the data and it all just sort of works.

801
00:41:12,800 --> 00:41:16,680
Speaker 1: It's like, man, math is correct, physics works, the universe

802
00:41:16,840 --> 00:41:21,320
Speaker 1: actually makes sense. It's incredible. I guess you're simultaneously impressed

803
00:41:21,360 --> 00:41:24,440
Speaker 1: by yourselves but also disappointed that you're so good at

804
00:41:24,480 --> 00:41:26,960
Speaker 1: figuring out the universe. Kind of yeah, it's not as

805
00:41:27,040 --> 00:41:30,080
Speaker 1: exciting an explanation is like we discovered a new way

806
00:41:30,080 --> 00:41:34,080
Speaker 1: that time flows, or gravity is broken, or something like that,

807
00:41:34,239 --> 00:41:36,560
Speaker 1: or we have a clump of hidden dark matter in

808
00:41:36,600 --> 00:41:39,400
Speaker 1: the Solar System that would be more exciting, but you

809
00:41:39,480 --> 00:41:42,920
Speaker 1: never know, Like science is about exploration, which means you

810
00:41:43,000 --> 00:41:46,120
Speaker 1: never know what you're gonna find. Usually it's boring dust

811
00:41:46,160 --> 00:41:49,879
Speaker 1: and rubble, but sometimes sometimes it's a real diamond, it's

812
00:41:49,880 --> 00:41:52,200
Speaker 1: a gem, something that gives you a clue about the

813
00:41:52,280 --> 00:41:54,359
Speaker 1: nature of reality, and you never know, which is why

814
00:41:54,440 --> 00:41:56,520
Speaker 1: you just gotta keep scratching, all right. So then this

815
00:41:56,680 --> 00:41:58,760
Speaker 1: is sort of in the community, this is the most

816
00:41:59,000 --> 00:42:01,880
Speaker 1: accepted explain aation of what happened. Like everyone feels like,

817
00:42:01,920 --> 00:42:05,719
Speaker 1: all right, these researchers totally nailed it, they totally explains it,

818
00:42:05,840 --> 00:42:08,520
Speaker 1: or is there still some sort of uncertainty about it both.

819
00:42:08,840 --> 00:42:11,960
Speaker 1: I think people accept this as an explanation for what

820
00:42:12,080 --> 00:42:14,879
Speaker 1: happened to Pioneer ten and Pioneer eleven, So that sort

821
00:42:14,880 --> 00:42:18,320
Speaker 1: of anomaly has been solved, but there are still plenty

822
00:42:18,360 --> 00:42:21,640
Speaker 1: of anomalies and how spacecraft moved, not just Pioneer ten

823
00:42:21,680 --> 00:42:24,600
Speaker 1: and Pioneer eleven, but every spacecraft that does one of

824
00:42:24,600 --> 00:42:27,920
Speaker 1: these sort of gravitational slingshots ends up going off in

825
00:42:27,920 --> 00:42:31,400
Speaker 1: the direction that we don't quite understand. This is called

826
00:42:31,440 --> 00:42:34,719
Speaker 1: the fly by anomally. Basically, every time one of these

827
00:42:34,719 --> 00:42:37,040
Speaker 1: things happens, it doesn't quite work out the way we

828
00:42:37,080 --> 00:42:40,600
Speaker 1: expect and nobody really understands it. So there's a long

829
00:42:40,680 --> 00:42:43,279
Speaker 1: list of things we don't understand about how things move

830
00:42:43,320 --> 00:42:45,880
Speaker 1: into Solar system. Even though as basic as just like

831
00:42:46,000 --> 00:42:49,760
Speaker 1: gravitational mechanics about things moving in the Solar System, still

832
00:42:49,840 --> 00:42:52,239
Speaker 1: have questions that need to be answered, right, which is

833
00:42:52,280 --> 00:42:55,000
Speaker 1: all the more impressive that they can. I'm gonna say

834
00:42:55,000 --> 00:42:57,520
Speaker 1: we because this is a good thing, So I'm gonna

835
00:42:57,760 --> 00:43:00,960
Speaker 1: play the royal we here. We can like land spacecraft

836
00:43:01,000 --> 00:43:03,239
Speaker 1: in Mars right and like know exactly where it's going

837
00:43:03,280 --> 00:43:05,839
Speaker 1: to land on the planet. That's that's so amazing. It's

838
00:43:05,880 --> 00:43:09,719
Speaker 1: really incredible what we the scientists and engineers have accomplished.

839
00:43:09,800 --> 00:43:14,399
Speaker 1: It's too bad what they messed up on. All right, Well,

840
00:43:14,440 --> 00:43:17,719
Speaker 1: that's the pioneer anomaly, and I guess we can reclassify

841
00:43:17,760 --> 00:43:22,480
Speaker 1: it now, Daniel as a pioneer nomally, or the pioneer

842
00:43:22,600 --> 00:43:27,520
Speaker 1: story or the high precision test of science, that is

843
00:43:27,560 --> 00:43:33,120
Speaker 1: the pioneer spacecraft. That's not as catchy, but maybe more accurate. Again,

844
00:43:33,160 --> 00:43:37,200
Speaker 1: another reminder of how you know vast space is I mean,

845
00:43:37,239 --> 00:43:40,680
Speaker 1: this thing is still within our backyard, just the solar SYSM.

846
00:43:40,719 --> 00:43:43,879
Speaker 1: And even even then, these distances are huge and there's

847
00:43:43,920 --> 00:43:45,360
Speaker 1: a lot that can happen out there when you go

848
00:43:45,360 --> 00:43:48,279
Speaker 1: out into deep space. Yeah, Pioneer ten is more than

849
00:43:48,360 --> 00:43:53,200
Speaker 1: twelve billion kilometers from Earth. It's tens of light hours

850
00:43:53,280 --> 00:43:56,520
Speaker 1: from Earth and moving away really really fast. It's destined

851
00:43:56,560 --> 00:43:59,440
Speaker 1: to reach another star system in about two million years.

852
00:43:59,719 --> 00:44:03,279
Speaker 1: That's sixty seven light years from here. So maybe in

853
00:44:03,480 --> 00:44:06,000
Speaker 1: two million and sixty seven years we'll get a message

854
00:44:06,040 --> 00:44:09,640
Speaker 1: back from the aliens saying thanks for your garbage, Thanks

855
00:44:09,640 --> 00:44:15,160
Speaker 1: for your garbage. With the hot front end, back end,

856
00:44:15,200 --> 00:44:18,080
Speaker 1: it's a hot back end. Let leave, we turn it

857
00:44:18,120 --> 00:44:19,800
Speaker 1: around and let's see if we can turn this around,

858
00:44:20,480 --> 00:44:23,200
Speaker 1: and we'll back into this cultural misunderstanding with the aliens.

859
00:44:23,520 --> 00:44:26,200
Speaker 1: All right, Well, we hope you enjoyed that. Thanks for

860
00:44:26,280 --> 00:44:36,319
Speaker 1: joining us, see you next time. Thanks for listening, and

861
00:44:36,360 --> 00:44:39,080
Speaker 1: remember that Daniel and Jorge explained. The Universe is a

862
00:44:39,120 --> 00:44:42,560
Speaker 1: production of I Heart Radio or more podcast from my

863
00:44:42,680 --> 00:44:46,239
Speaker 1: Heart Radio, visit the I heart Radio app, Apple Podcasts,

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00:44:46,360 --> 00:44:54,479
Speaker 1: or wherever you listen to your favorite shows. Yeah,