1 00:00:00,000 --> 00:00:02,000 Humming sound 2 00:00:02,000 --> 00:00:09,220 Music 3 00:00:09,220 --> 00:00:12,075 Since the 1960's, scientists have suspected that 4 00:00:12,075 --> 00:00:15,115 frozen water could survive in permanently shadowed craters 5 00:00:15,115 --> 00:00:18,165 at the Moon's poles. Both hydrogen and oxygen 6 00:00:18,165 --> 00:00:20,555 could be trapped within the lunar soil. 7 00:00:20,795 --> 00:00:23,115 So to find water on the Moon, scientists 8 00:00:23,115 --> 00:00:26,025 are looking for indications of hydrogen using the Lunar 9 00:00:26,025 --> 00:00:28,885 Reconnaissance Orbiter's LEND neutron detector. 10 00:00:29,125 --> 00:00:32,185 By observing the interaction of neutrons with the lunar soil, 11 00:00:32,185 --> 00:00:35,640 scientists can interpret how much hydrogen is likely to be present. 12 00:00:35,900 --> 00:00:38,385 In order to make a detailed interpretation, however, 13 00:00:38,385 --> 00:00:41,840 LEND needs to observe a large number of neutrons 14 00:00:42,565 --> 00:00:45,135 Because LRO is constantly moving, LEND is never over 15 00:00:45,135 --> 00:00:48,075 one place long enough to count many neutrons. 16 00:00:48,075 --> 00:00:51,085 So, to make a detailed interpretation of neutron flux, 17 00:00:51,085 --> 00:00:54,680 scientists add together many measurements from many orbits. 18 00:00:55,300 --> 00:00:58,300 With each orbit LEND's dataset gets larger 19 00:00:58,305 --> 00:01:01,105 and its picture of neutron flux continually improves 20 00:01:01,105 --> 00:01:04,620 over time. The dark blue regions in this visualization 21 00:01:04,620 --> 00:01:07,015 are places on the south pole of the Moon with a 22 00:01:07,015 --> 00:01:10,425 suppressed flux of neutrons because of their interaction of hydrogen. 23 00:01:10,795 --> 00:01:13,555 These areas strongly suggest the presence of water 24 00:01:13,555 --> 00:01:15,005 frozen within the soil. 25 00:01:15,005 --> 00:01:16,285 Music 26 00:01:16,285 --> 00:01:19,295 While previous lunar missions have observed indications of hydrogen 27 00:01:19,300 --> 00:01:22,720 at the Moon's south pole, the LEND measurements for the first time 28 00:01:22,720 --> 00:01:24,775 pinpoint where hydrogen, and thus water, 29 00:01:24,775 --> 00:01:26,335 is likely to exist. 30 00:01:27,005 --> 00:01:29,755 By combining years of LEND data, scientists 31 00:01:29,755 --> 00:01:33,065 see accumulating evidence that there is water on the Moon. 32 00:01:33,505 --> 00:01:36,045 And as LRO continues to return data, 33 00:01:36,045 --> 00:01:39,315 our picture of the Moon and its water will continue to get better 34 00:01:39,315 --> 00:01:40,695 in the years ahead. 35 00:01:40,700 --> 00:01:44,560 Music 36 00:01:44,600 --> 00:01:49,760 Beep, Beep, Beep 37 00:01:49,760 --> 00:01:53,600 Music