WEBVTT FILE 1 00:00:00.080 --> 00:00:04.140 music throughout 2 00:00:04.160 --> 00:00:08.190 Narrator: : To every astronaut or spacecraft, the Sun is a damaging source of radiation. 3 00:00:08.210 --> 00:00:12.060 All objects traveling through space must contend with this hazard, including planets. Even the moon has the scars 4 00:00:12.080 --> 00:00:16.170 to prove it. New NASA research suggests that some of the coloration 5 00:00:16.190 --> 00:00:20.380 we see on the moon could be a form of sunburn. 6 00:00:20.400 --> 00:00:26.920 Andrew Poppe: The leading hypothesis is that the magnetic fields are blocking 7 00:00:26.940 --> 00:00:31.110 some portion of the solar wind from reaching the surface 8 00:00:31.130 --> 00:00:35.300 Narrator: The solar wind is the Sun’s continuous outflow of particles and radiation that fills the inner solar system. Earth’s magnetic field provides a strong, 9 00:00:35.320 --> 00:00:39.400 global shield against it. However, the magnetic field on the moon is much weaker, 10 00:00:39.420 --> 00:00:43.650 and it forms only small, localized bubbles of protection. In these spots, 11 00:00:43.670 --> 00:00:47.840 the Sun’s particles can be reflected back into the solar wind or funneled to nearby regions. 12 00:00:47.860 --> 00:00:52.000 The shielded areas under the magnetic field form pale swirls. 13 00:00:52.020 --> 00:00:56.740 The bordering parts become darker. The contrast is so prominent, 14 00:00:56.760 --> 00:01:00.940 we can see it from Earth. 15 00:01:00.960 --> 00:01:05.020 Poppe: Those are regions acting as this magnetic sunscreen. You know, sometimes you put on sunscreen 16 00:01:05.040 --> 00:01:09.190 and you miss a tiny little bit, and then you have are really bright red spot on your skin where you missed it. 17 00:01:09.210 --> 00:01:13.370 That's in some ways the analogy for the region of the moon that is extra exposed. 18 00:01:13.390 --> 00:01:17.550 Narrator: Unfortunately, the moon’s patches of magnetic field are not 19 00:01:17.570 --> 00:01:21.600 robust enough to completely protect human explorers from the Sun’s radiation, 20 00:01:21.620 --> 00:01:25.790 but further study of lunar magnetic fields could lay the groundwork for 21 00:01:25.810 --> 00:01:33.010 future innovations. Poppe: It gives a test case for what if we got a strong enough magnetic field that perhaps 22 00:01:33.030 --> 00:01:37.170 we could produce artificially? That’s a question that remains to be answered, 23 00:01:37.190 --> 00:01:41.230 but I think that crustal magnetic fields on the moon and lunar swirls kind of provide a hint in that direction, that we might be able to learn something about. 24 00:01:41.250 --> 00:01:45.330 tone 25 00:01:45.350 --> 00:01:49.460 tone 26 00:01:49.480 --> 00:01:53.620 spacecraft beeping 27 00:01:53.640 --> 00:01:54.428 spacecraft beeping