1 00:00:00,020 --> 00:00:04,030 music 2 00:00:04,050 --> 00:00:08,080 music 3 00:00:08,100 --> 00:00:12,110 music 4 00:00:12,130 --> 00:00:16,140 Tom Moore: Magnetic reconnection is the process of disconnecting or connecting 5 00:00:16,160 --> 00:00:20,190 the magnetic fields to each other, directing energy into the Earth on the dayside 6 00:00:20,210 --> 00:00:24,210 and then letting it go on the nightside. The interplay between the 7 00:00:24,230 --> 00:00:28,260 2 is what produces all the space weather around the Earth that 8 00:00:28,280 --> 00:00:32,280 has big effects, can damage our spacecraft, can 9 00:00:32,300 --> 00:00:36,290 hurt astronauts, can upset the flow of electrical energy in our electric grid 10 00:00:36,310 --> 00:00:40,350 on the surface of the Earth. MMS is a mission with 4 spacecraft 11 00:00:40,370 --> 00:00:44,380 that travel in formation, in an orbit that takes them 12 00:00:44,400 --> 00:00:48,450 out into 2 special places near the Earth, 13 00:00:48,470 --> 00:00:52,470 one upstream toward the sun, one downstream away from the sun. 14 00:00:52,490 --> 00:00:56,490 Both of those place have magnetic reconnection. 15 00:00:56,510 --> 00:01:00,510 We have never before MMS had the ability to 16 00:01:00,530 --> 00:01:04,570 essentially run the camera fast enough to catch it 17 00:01:04,590 --> 00:01:08,600 as it goes by, to make many measurements per second. 18 00:01:08,620 --> 00:01:12,650 The science payload for MMS is all mounted on a single deck plate. 19 00:01:12,670 --> 00:01:16,670 It consists of some 25 boxes per spacecraft, 20 00:01:16,690 --> 00:01:20,700 divided into 3 general groups of instruments. That's those measuring 21 00:01:20,720 --> 00:01:24,710 fields (electric and magnetic), those for measuring plasmas, 22 00:01:24,730 --> 00:01:28,720 and a third for measuring energetic particles. 23 00:01:28,740 --> 00:01:32,760 The magnetic field sensors are out on arms that extend away from the spacecraft. They are fixed, but the spacecraft is 24 00:01:32,780 --> 00:01:36,780 spinning slowly, about once every 20 seconds. 25 00:01:36,800 --> 00:01:40,830 The electric field is quite a bit different. It consists of 4 wires 26 00:01:40,850 --> 00:01:44,890 that extend out away from the spacecraft with a ball out on the end of each of them. 27 00:01:44,910 --> 00:01:48,940 that actually contacts the plasma. 28 00:01:48,960 --> 00:01:52,980 All 4 of those are spinning around with the spacecraft with this 20 second period. 29 00:01:53,000 --> 00:01:57,010 And then there's a third axis, there's booms that extend along 30 00:01:57,030 --> 00:02:01,070 the spin axis of the spacecraft, both upward and downward with the probe at the end. 31 00:02:01,090 --> 00:02:05,090 So you've got 3 components of the electric field. They can measure everything from 32 00:02:05,110 --> 00:02:09,140 up to small wiggles and vibrations of the electric field. 33 00:02:09,160 --> 00:02:13,180 Another sensor is called the search coil magnetometer is just a loop of wire 34 00:02:13,200 --> 00:02:17,210 connected to a suitable amplifier, and it is designed 35 00:02:17,230 --> 00:02:21,240 to measure the fluctuations at higher frequencies than you could get 36 00:02:21,260 --> 00:02:25,290 with the DC magnetometers. For the plasmas 37 00:02:25,310 --> 00:02:29,320 8 boxes, 2 boxes at each of the 4 points of the compass on the spacecraft. 38 00:02:29,340 --> 00:02:33,350 Those are equally spaced all around the spacecraft. That is a real 39 00:02:33,370 --> 00:02:37,400 key ingredient for being able to see the 40 00:02:37,420 --> 00:02:41,440 entire sky instantaneously, without waiting for the spacecraft to spin 41 00:02:41,460 --> 00:02:45,460 Then there is also the hot plasma composition analyzer 42 00:02:45,480 --> 00:02:49,500 1 per spacecraft. It has sensor head that looks all around in a 43 00:02:49,520 --> 00:02:53,530 360 degree annulus that sticks out the side of the spacecraft 44 00:02:53,550 --> 00:02:57,560 and sweeps out the whole sky twice per spin. 45 00:02:57,580 --> 00:03:01,570 It measures the chemical species of the particles. 46 00:03:01,590 --> 00:03:05,590 Next are the accelerated particle analyzers that are measuring much more energetic particles 47 00:03:05,610 --> 00:03:09,630 that are accelerated by the reconnection process. 48 00:03:09,650 --> 00:03:13,660 Ultimately, what we will be doing is comparing our observations with simulations of the entire magnetoshere 49 00:03:13,680 --> 00:03:17,730 as it is influenced with the solar wind coming in, down to the 50 00:03:17,750 --> 00:03:21,770 details of what reconnection is occurring. People who do 51 00:03:21,790 --> 00:03:25,800 those simulations try to apply them to all other kinds of places, like in the solar 52 00:03:25,820 --> 00:03:29,850 atmosphere and other astrophysical stars 53 00:03:29,870 --> 00:03:33,900 and other objects. They are very interested in 54 00:03:33,920 --> 00:03:37,990 whether those simulations are accurate and reflect reality well 55 00:03:38,010 --> 00:03:42,000 This is going to be the first time we actually bump them up against hard data of what's going 56 00:03:42,020 --> 00:03:46,050 in there. I am almost certain, I'm very certain, they are gonna learn something 57 00:03:46,070 --> 00:03:50,100 from that and the simulations will get better. 58 00:03:50,120 --> 00:03:54,120 We are going to measure things at rates that have never been done before, in places that 59 00:03:54,140 --> 00:03:58,130 have been hard to reach and even see, because they go by to fast 60 00:03:58,150 --> 00:04:02,160 so, it's going to be fantastic. 61 00:04:02,180 --> 00:04:04,391 beeping