1 00:00:00,120 --> 00:00:01,920 Speaker 1: This Day in History Class is a production of I 2 00:00:02,080 --> 00:00:07,840 Speaker 1: Heart Radio. Greetings everyone, Welcome to This Day in History class, 3 00:00:08,119 --> 00:00:14,360 Speaker 1: where we learn a smidgen of history every day. Today 4 00:00:14,520 --> 00:00:27,840 Speaker 1: is July fourteen. The day was July four The National 5 00:00:27,880 --> 00:00:31,960 Speaker 1: Aeronautics in Space Administration, better known as NASA, landed the 6 00:00:32,000 --> 00:00:36,640 Speaker 1: Mars Pathfinder on Mars Is aries Valis. It's robotic rover, 7 00:00:36,920 --> 00:00:40,320 Speaker 1: named so Journer, became the first wheeled vehicle to explore 8 00:00:40,320 --> 00:00:44,600 Speaker 1: the surface of another planet. Part of Pathfinders purpose was 9 00:00:44,640 --> 00:00:47,680 Speaker 1: to prove that spacecraft could be cheaper, faster, and better. 10 00:00:48,240 --> 00:00:51,080 Speaker 1: The mission would demonstrate the technology that was necessary to 11 00:00:51,080 --> 00:00:54,120 Speaker 1: get a lander and robotic rover to the surface of 12 00:00:54,160 --> 00:00:58,520 Speaker 1: Mars on a lower budget. The lander cost fifty million 13 00:00:58,560 --> 00:01:01,400 Speaker 1: dollars to develop and build, while the rover cost about 14 00:01:01,400 --> 00:01:05,840 Speaker 1: twenty five million dollars including launch and operations. The Mars 15 00:01:05,920 --> 00:01:09,399 Speaker 1: Pathfinder mission cost two hundred and sixty five million dollars. 16 00:01:10,480 --> 00:01:13,080 Speaker 1: The Mars Pathfinder mission would be the first time at 17 00:01:13,080 --> 00:01:16,240 Speaker 1: spacecraft landed on the planet in more than two decades. 18 00:01:17,360 --> 00:01:20,280 Speaker 1: The previous time was in nineteen seventy six, when Viking 19 00:01:20,319 --> 00:01:23,920 Speaker 1: one and Viking two made it to Mars. Landing was 20 00:01:23,959 --> 00:01:27,560 Speaker 1: a difficult tash for spacecraft. In fact, many landers at 21 00:01:27,560 --> 00:01:30,679 Speaker 1: the Soviet Union, Russia, and United States sent to Mars 22 00:01:30,720 --> 00:01:35,880 Speaker 1: were lost or destroyed. Mars Pathfinder was launched on December four, nineteen. 23 00:01:37,080 --> 00:01:39,600 Speaker 1: The robotic spacecraft was made up of an eight hundred 24 00:01:39,640 --> 00:01:43,240 Speaker 1: and sixteen pound or three hundred and seventy k lander 25 00:01:43,600 --> 00:01:47,600 Speaker 1: officially called the Carl Sagan Memorial Station, and the twenty 26 00:01:47,640 --> 00:01:51,360 Speaker 1: three pound rovers to Journer. The rover was named after 27 00:01:51,440 --> 00:01:55,440 Speaker 1: Sojourner Truth, an abolitionist and activists in the nineteenth century. 28 00:01:56,080 --> 00:02:00,360 Speaker 1: On July four, nine seven, Mars Pathfinder entered a thin 29 00:02:00,600 --> 00:02:05,120 Speaker 1: Martian atmosphere, taking atmospheric measurements. As it descended towards the 30 00:02:05,160 --> 00:02:09,760 Speaker 1: surface of the planet, a heat shield slowed the spacecraft down. 31 00:02:10,120 --> 00:02:13,440 Speaker 1: Then a parachute was deployed, slowing the craft descent through 32 00:02:13,480 --> 00:02:17,360 Speaker 1: the atmosphere. It then released its heat shield and the 33 00:02:17,440 --> 00:02:20,360 Speaker 1: lander separated and lowered from the back sheel on a tether. 34 00:02:21,520 --> 00:02:25,040 Speaker 1: Air bags inflated about ten seconds before landing, forming a 35 00:02:25,080 --> 00:02:29,440 Speaker 1: protective shield around the lander. Three solid rockets fired to 36 00:02:29,520 --> 00:02:32,440 Speaker 1: slow the descent even more. The tether was cut and 37 00:02:32,480 --> 00:02:36,280 Speaker 1: the lander dropped to the surface. It bounced more than 38 00:02:36,320 --> 00:02:38,920 Speaker 1: a dozen times before it rolled and stopped two and 39 00:02:38,919 --> 00:02:43,120 Speaker 1: a half minutes after landing Mars. Pathfinder had landed on 40 00:02:43,160 --> 00:02:46,239 Speaker 1: the surface of the red planet in a floodplane in 41 00:02:46,280 --> 00:02:50,400 Speaker 1: the northern hemisphere called Aries Vallas, chosen for its safety 42 00:02:50,480 --> 00:02:53,239 Speaker 1: and the variety of rocks present there that sword Journer 43 00:02:53,280 --> 00:02:56,880 Speaker 1: could analyze. It made it to Mars surface less than 44 00:02:56,919 --> 00:03:00,400 Speaker 1: a second from its projected landing time. The whole process 45 00:03:00,400 --> 00:03:05,320 Speaker 1: of entry, descent, and landing lasted about four minutes. After landing, 46 00:03:05,360 --> 00:03:10,280 Speaker 1: the airbags deflated and Pathfinder opened its solar panels. The 47 00:03:10,360 --> 00:03:13,640 Speaker 1: lander sent back data it had collected during entry and landing, 48 00:03:13,919 --> 00:03:16,520 Speaker 1: and it sent images that it took of the landing area. 49 00:03:17,720 --> 00:03:20,799 Speaker 1: So Journer was soon released from the lander down a ramp. 50 00:03:21,400 --> 00:03:24,160 Speaker 1: So Journer had two black and white cameras to navigate, 51 00:03:24,480 --> 00:03:28,440 Speaker 1: one color camera, and an alpha proton expert spectrometer for 52 00:03:28,480 --> 00:03:32,640 Speaker 1: analyzing rocks and soil. Its top speed was about two 53 00:03:32,639 --> 00:03:37,680 Speaker 1: ft per minute. The rover analyzed the composition of nearby rocks, 54 00:03:37,720 --> 00:03:43,360 Speaker 1: which scientists named Barnacle, Bill, Yogi, and Scooby Doo. NASA 55 00:03:43,440 --> 00:03:45,600 Speaker 1: said that the data it gathered could be evidence of 56 00:03:45,640 --> 00:03:50,160 Speaker 1: a more water rich Mars. The lander relayed information from 57 00:03:50,160 --> 00:03:52,760 Speaker 1: the rover to Earth and took pictures of the sky 58 00:03:52,880 --> 00:03:56,560 Speaker 1: and its surroundings. It also tested the magnetic properties of 59 00:03:56,640 --> 00:04:00,520 Speaker 1: dust on the planet. So Journer was designed to last 60 00:04:00,560 --> 00:04:03,560 Speaker 1: seven days, but it ended up staying in operation for 61 00:04:03,600 --> 00:04:07,120 Speaker 1: eighty four days. It traveled about three and thirty feet 62 00:04:07,200 --> 00:04:11,440 Speaker 1: during the mission. The lander was designed to last thirty days, 63 00:04:11,760 --> 00:04:15,800 Speaker 1: but the final data transmission from Pathfinder was received on September. 64 00:04:18,839 --> 00:04:22,479 Speaker 1: The battery, which had been repeatedly charged and discharged, may 65 00:04:22,560 --> 00:04:26,800 Speaker 1: have failed. The lander and rover sent more than seventeen 66 00:04:26,839 --> 00:04:30,760 Speaker 1: thousand images back to Earth. It also provided analysis of 67 00:04:30,760 --> 00:04:33,880 Speaker 1: the rocks and soil on Mars and data on wind 68 00:04:33,920 --> 00:04:37,920 Speaker 1: and weather. The technology used in the Mars Pathfinder mission 69 00:04:38,040 --> 00:04:41,520 Speaker 1: was later used with some changes, on the Mars Exploration 70 00:04:41,720 --> 00:04:46,240 Speaker 1: Rover mission, which began in two thousand three. I'm Eve 71 00:04:46,279 --> 00:04:48,679 Speaker 1: Steff Coote and hopefully you know a little more about 72 00:04:48,720 --> 00:04:52,600 Speaker 1: history today than you did yesterday. If there are any 73 00:04:52,680 --> 00:04:55,479 Speaker 1: upcoming days in history that you'd really like me to 74 00:04:55,520 --> 00:04:57,960 Speaker 1: cover on the show, give us a shout on social 75 00:04:57,960 --> 00:05:04,200 Speaker 1: media at t D I h C Podcast. You can 76 00:05:04,240 --> 00:05:07,400 Speaker 1: subscribe to This Day in History class on Apple podcasts, 77 00:05:07,440 --> 00:05:10,400 Speaker 1: the I heart Radio app, or wherever you get your podcasts. 78 00:05:10,960 --> 00:05:22,360 Speaker 1: Tune in tomorrow for Another Day in History. For more 79 00:05:22,400 --> 00:05:24,920 Speaker 1: podcasts from I heart Radio, visit the iHeart Radio app, 80 00:05:25,000 --> 00:05:27,560 Speaker 1: Apple Podcasts, or wherever you listen to your favorite shows.