1 00:00:02,600 --> 00:00:03,980 The Sun. 2 00:00:04,000 --> 00:00:05,380 It’s the solar system’s engine, 3 00:00:05,400 --> 00:00:08,480 and the only star in the sky that gets our attention… 4 00:00:08,500 --> 00:00:10,480 every day. 5 00:00:10,500 --> 00:00:11,480 But up close, 6 00:00:11,500 --> 00:00:14,880 it’s unlike anything we can see from Earth. 7 00:00:14,900 --> 00:00:16,180 It’s ferocious— 8 00:00:16,200 --> 00:00:19,400 a writhing mass of nuclear chaos, 9 00:00:19,420 --> 00:00:21,180 tangled magnetic lines, 10 00:00:21,200 --> 00:00:24,980 and a constant wind with inconceivably high temperatures 11 00:00:25,000 --> 00:00:32,180 and speeds close to a million miles an hour. 12 00:00:32,200 --> 00:00:35,980 Over the years NASA has sent probes all over the solar system… 13 00:00:36,000 --> 00:00:37,580 ...but never to the Sun. 14 00:00:37,600 --> 00:00:39,480 Check this out. 15 00:00:39,500 --> 00:00:41,180 This is the Parker Solar Probe… 16 00:00:41,200 --> 00:00:46,180 …and it’s going to be humanity’s first mission assigned to touch the Sun. 17 00:00:46,200 --> 00:00:49,970 It will fly to within 4 million miles of the Sun’s surface 18 00:00:49,990 --> 00:00:51,680 confronting brutal radiation 19 00:00:51,700 --> 00:00:56,580 and temperatures that can reach 1,000,000 degrees Fahrenheit. 20 00:00:56,600 --> 00:00:58,290 Parker Solar Probe has been prepped 21 00:00:58,310 --> 00:01:01,880 to fly right through that unforgiving atmosphere. 22 00:01:01,900 --> 00:01:05,180 It's a rough journey. 23 00:01:05,200 --> 00:01:07,780 Typically, if you want to head out into the solar system, 24 00:01:07,800 --> 00:01:10,280 you merge with orbital traffic. 25 00:01:10,300 --> 00:01:12,780 But if you want to head toward the center of the solar system, 26 00:01:12,800 --> 00:01:14,480 you've got to run the other way… 27 00:01:14,500 --> 00:01:17,080 and it takes a lot of energy. 28 00:01:17,100 --> 00:01:20,380 once it arrives, the spacecraft has got to take the heat. 29 00:01:20,400 --> 00:01:22,880 Bathed in radiation as it swoops in close, 30 00:01:22,900 --> 00:01:24,780 Parker Solar Probe will use an advanced 31 00:01:24,800 --> 00:01:26,780 carbon/carbon composite heat shield 32 00:01:26,800 --> 00:01:27,380 o protect its delicate instruments. 33 00:01:27,400 --> 00:01:32,280 And here’s a technical triumph: 34 00:01:32,300 --> 00:01:34,580 the spacecraft’s thermal regulation system 35 00:01:34,600 --> 00:01:37,180 will use just a single gallon of ordinary water 36 00:01:37,200 --> 00:01:38,880 H 2 O 37 00:01:38,900 --> 00:01:44,780 to collect and then dissipate heat…just like a car radiator. 38 00:01:44,800 --> 00:01:46,540 It will fly into the corona, 39 00:01:46,560 --> 00:01:50,340 the super hot region of gas and plasma surrounding the Sun. 40 00:01:50,360 --> 00:01:52,460 There’s hardly a there there, 41 00:01:52,480 --> 00:01:55,920 as high energy particles fly outward like streamers. 42 00:01:55,940 --> 00:01:58,860 But – and this is another weird thing about the sun- 43 00:01:58,880 --> 00:02:02,580 -the corona is hotter than the surface of the star itself. 44 00:02:02,600 --> 00:02:04,440 We have a few good theories about this– 45 00:02:04,460 --> 00:02:06,680 but we're really not sure why. 46 00:02:06,700 --> 00:02:09,570 There's some process in the atmosphere that keeps heating it up 47 00:02:09,590 --> 00:02:11,620 even as it gets further away from the core. 48 00:02:11,640 --> 00:02:15,330 Parker Solar Probe is going to try and figure it out. 49 00:02:15,350 --> 00:02:18,170 The corona also propels the solar wind out into space 50 00:02:18,190 --> 00:02:19,590 at incredible speeds 51 00:02:19,610 --> 00:02:21,990 way beyond the orbit of Pluto. 52 00:02:22,010 --> 00:02:27,660 No one knows for sure what accelerates it so far so fast. 53 00:02:27,680 --> 00:02:31,170 Parker Solar Probe is going to fly right through the origin of this wind, 54 00:02:31,190 --> 00:02:36,640 right where it starts, to figure out how the whole system works 55 00:02:36,660 --> 00:02:41,690 We can’t see those processes from Earth, or even from space. 56 00:02:41,710 --> 00:02:48,080 Parker Solar Probe is our first direct encounter with a star. 57 00:02:48,100 --> 00:02:51,780 Our Sun is the only star we can visit…. 58 00:02:51,800 --> 00:02:52,680 …which means this mission will gather 59 00:02:52,700 --> 00:02:57,470 important information about how stars work…everywhere. 60 00:02:57,490 --> 00:03:01,520 That’s information we can only get by going straight to the source. 61 00:03:01,540 --> 00:03:04,280 Some journeys are harder than others. 62 00:03:04,300 --> 00:03:08,880 Some destinations are further, higher, hotter. 63 00:03:08,900 --> 00:03:12,490 But the only way to explore a new destination 64 00:03:12,510 --> 00:03:15,190 is to actually make the journey. 65 00:03:15,210 --> 00:03:17,290 Parker Solar Probe: 66 00:03:17,310 --> 00:03:31,790 See you on The Sun.