1 00:00:01,800 --> 00:00:07,960 Speaker 1: Welcome to Brainstuff, a production of iHeartRadio. Hey Brainstuff, Lauren 2 00:00:08,000 --> 00:00:10,959 Speaker 1: vogel Bomb here with a classic episode of the podcast 3 00:00:11,480 --> 00:00:14,160 Speaker 1: that this one has to do with how rainbows work, 4 00:00:14,440 --> 00:00:17,160 Speaker 1: how to find them, why you can't reach the end 5 00:00:17,200 --> 00:00:20,840 Speaker 1: of one, and how they're not actually bows at all. 6 00:00:23,040 --> 00:00:26,520 Speaker 1: Hey Brainstuff, Lauren Vogelbomb here. As far as get rich 7 00:00:26,600 --> 00:00:29,400 Speaker 1: quick schemes go, stumbling upon gold the end of a 8 00:00:29,480 --> 00:00:33,519 Speaker 1: rainbow sounds pretty delightful. But is it actually possible to 9 00:00:33,560 --> 00:00:36,000 Speaker 1: get to the end of a rainbow? And if so, 10 00:00:36,320 --> 00:00:39,600 Speaker 1: what would you find when you got there. Let's start 11 00:00:39,640 --> 00:00:43,320 Speaker 1: with the bad news. Leprechns are liars. You cannot reach 12 00:00:43,360 --> 00:00:45,360 Speaker 1: the end of a rainbow that appears in the sky. 13 00:00:45,880 --> 00:00:47,920 Speaker 1: If you were to mark on a map the place 14 00:00:47,920 --> 00:00:50,040 Speaker 1: where the rainbow seems to meet the land, and then 15 00:00:50,080 --> 00:00:53,040 Speaker 1: travel to that location, you would not be standing inside 16 00:00:53,040 --> 00:00:56,200 Speaker 1: a glorious pillar of colors. There would be nothing there 17 00:00:56,480 --> 00:00:59,720 Speaker 1: except probably the fresh smell of a recent rain shower. 18 00:01:00,680 --> 00:01:02,800 Speaker 1: To understand why this is, we need to look at 19 00:01:02,880 --> 00:01:07,000 Speaker 1: how rainbows form. Rainbows are created when sunlight reflects and 20 00:01:07,080 --> 00:01:10,120 Speaker 1: refracts through water. Droplets suspend in the air in front 21 00:01:10,160 --> 00:01:12,960 Speaker 1: of you while the sun is behind you. Those water 22 00:01:13,040 --> 00:01:16,680 Speaker 1: droplets act like both a mirror and a prism. Like 23 00:01:16,880 --> 00:01:19,920 Speaker 1: a mirror, they reflect the sunlight back towards you, but 24 00:01:20,160 --> 00:01:23,120 Speaker 1: like a prism, they also bend and disperse that light. 25 00:01:24,000 --> 00:01:26,240 Speaker 1: This is because rays of light shining through the air 26 00:01:26,480 --> 00:01:29,320 Speaker 1: change speed when they enter a different medium, for example, 27 00:01:29,400 --> 00:01:33,280 Speaker 1: droplets of water. This sudden change in speed bends the 28 00:01:33,319 --> 00:01:36,520 Speaker 1: trajectory of the light and disperses white light into the 29 00:01:36,560 --> 00:01:39,840 Speaker 1: whole roy g Bib spectrum. The reason you see a 30 00:01:40,000 --> 00:01:42,880 Speaker 1: nice ordered gradient of colors within a rainbow going from 31 00:01:42,959 --> 00:01:46,560 Speaker 1: red to violet is because this refraction bends each of 32 00:01:46,560 --> 00:01:49,960 Speaker 1: the different colors of light at a slightly different angle. So, 33 00:01:50,040 --> 00:01:53,200 Speaker 1: for example, red light bends at forty two degrees, violet 34 00:01:53,280 --> 00:01:56,040 Speaker 1: light bends at forty degrees, and all the other colors 35 00:01:56,080 --> 00:02:01,040 Speaker 1: are somewhere in between. So okay, let's find a rainbow. 36 00:02:01,080 --> 00:02:04,000 Speaker 1: To do this, you need to locate your antisolar point. 37 00:02:04,520 --> 00:02:07,160 Speaker 1: Your antisolar point is the point in space that's one 38 00:02:07,240 --> 00:02:10,000 Speaker 1: hundred and eighty degrees or exactly opposite from the sun. 39 00:02:10,680 --> 00:02:12,760 Speaker 1: A simple way to find this is to go outside 40 00:02:12,760 --> 00:02:15,560 Speaker 1: and look for the shadow of your own head. That's 41 00:02:15,639 --> 00:02:19,400 Speaker 1: your antisolar point. Now imagine drawing a line straight from 42 00:02:19,440 --> 00:02:21,959 Speaker 1: the sun through your head to the shadow of your head. 43 00:02:22,639 --> 00:02:26,120 Speaker 1: Now look up. If there is a rainbow to be seen, 44 00:02:26,440 --> 00:02:28,440 Speaker 1: you will find it by facing away from the sun 45 00:02:28,639 --> 00:02:33,440 Speaker 1: and looking forty two degrees above your antisolar point. Notice 46 00:02:33,440 --> 00:02:36,799 Speaker 1: that the apparent location of your rainbow depends on three things. 47 00:02:37,360 --> 00:02:40,359 Speaker 1: Where the sun is, where the water droplets are, and 48 00:02:40,400 --> 00:02:43,880 Speaker 1: where your eyes are. Change any one of those variables 49 00:02:43,919 --> 00:02:46,799 Speaker 1: and you'll see a different rainbow or none at all. 50 00:02:48,160 --> 00:02:50,560 Speaker 1: So no matter where you see your rainbow, if you 51 00:02:50,600 --> 00:02:52,840 Speaker 1: try to walk out to meet it, you'll be changing 52 00:02:52,840 --> 00:02:55,240 Speaker 1: the variable of your own position, and you could be 53 00:02:55,280 --> 00:02:59,160 Speaker 1: walking forever, or at least until your rainbow disappears. Trying 54 00:02:59,160 --> 00:03:00,799 Speaker 1: to find the end of a rain rainbow is sort 55 00:03:00,800 --> 00:03:02,240 Speaker 1: of like trying to walk to the end of your 56 00:03:02,240 --> 00:03:05,600 Speaker 1: own shadow. Somebody else could stand at the apparent end 57 00:03:05,600 --> 00:03:08,640 Speaker 1: of your shadow or rainbow, but you will never ever 58 00:03:08,880 --> 00:03:13,080 Speaker 1: reach this location yourself. You can, of course, find earthly 59 00:03:13,160 --> 00:03:15,720 Speaker 1: rainbows in a waterfall or the spray of a sprinkler 60 00:03:15,800 --> 00:03:18,480 Speaker 1: or hose. You might even perceive yourself to be standing 61 00:03:18,560 --> 00:03:20,400 Speaker 1: right next to one, depending on the angle of light 62 00:03:20,480 --> 00:03:24,280 Speaker 1: coming into the water. But here's one more thing. Those 63 00:03:24,360 --> 00:03:28,520 Speaker 1: rainbows you see in the sky aren't actually bows. Rainbows 64 00:03:28,600 --> 00:03:32,160 Speaker 1: are circular. Usually when you're standing on the ground, most 65 00:03:32,160 --> 00:03:35,680 Speaker 1: of the rainbow is blocked by the horizon. In rare cases, 66 00:03:35,720 --> 00:03:37,800 Speaker 1: like if you're in an airplane, you'll be able to 67 00:03:37,800 --> 00:03:43,720 Speaker 1: see the entire rainbow. Hoop, rain loop, rainhole. It's around 68 00:03:43,800 --> 00:03:48,600 Speaker 1: spectacular beauty, but there's an obvious takeaway from this it 69 00:03:48,640 --> 00:03:55,280 Speaker 1: doesn't ever actually meet the ground anywhere. Today's episode is 70 00:03:55,320 --> 00:03:59,120 Speaker 1: based on a videoscript orhoustopworks dot com written by Joe McCormick. 71 00:03:59,480 --> 00:04:01,800 Speaker 1: To hear more from Joe, check out his podcast stuff 72 00:04:01,840 --> 00:04:04,920 Speaker 1: to Blow Your Mind. Brainstuff is a production of iHeartRadio 73 00:04:04,960 --> 00:04:08,200 Speaker 1: in partnership withhstuffworks dot Com and is produced by Tyler Klang. 74 00:04:08,600 --> 00:04:11,920 Speaker 1: Before more podcasts my heart Radio, visit the iHeartRadio app, 75 00:04:12,000 --> 00:04:14,880 Speaker 1: Apple Podcasts, or wherever you listen to your favorite shows.