WEBVTT 1 00:00:00.470 --> 00:00:02.830 [pleasant music playing] 2 00:00:02.830 --> 00:00:04.720 What's Up for December. 3 00:00:04.720 --> 00:00:07.110 Your early evening highlights. 4 00:00:07.110 --> 00:00:08.890 A chance to catch a comet 5 00:00:08.890 --> 00:00:11.510 and the annual Geminid meteors. 6 00:00:11.510 --> 00:00:13.250 line:15% On December 6th through the 10th, 7 00:00:13.250 --> 00:00:15.940 line:15% look westward following sunset for the Moon, 8 00:00:15.940 --> 00:00:19.180 line:15% visiting Venus, Saturn, and Jupiter in turn. 9 00:00:19.180 --> 00:00:21.490 line:15% The Moon's crescent fills out as it appears higher 10 00:00:21.490 --> 00:00:24.450 line:15% in the sky each evening, over the course of the week. 11 00:00:24.450 --> 00:00:27.600 Enjoy the view of dazzling Venus as our "evening star" 12 00:00:27.600 --> 00:00:29.070 while it lasts though. 13 00:00:29.070 --> 00:00:31.910 Our cloud-covered neighbor planet will sink ever closer 14 00:00:31.910 --> 00:00:34.010 to the horizon during the month disappearing 15 00:00:34.010 --> 00:00:36.140 for most of us by New Years'. 16 00:00:36.140 --> 00:00:38.920 It'll reappear in late January as a morning planet 17 00:00:38.920 --> 00:00:40.320 preceding the sunrise, 18 00:00:40.320 --> 00:00:41.780 and won't be back in evening skies 19 00:00:41.780 --> 00:00:44.055 until December of next year. 20 00:00:44.055 --> 00:00:45.180 [Whoosh] 21 00:00:45.180 --> 00:00:46.150 Next in December, 22 00:00:46.150 --> 00:00:48.080 line:15% there's a recently discovered comet 23 00:00:48.080 --> 00:00:49.750 line:15% on its way into the inner solar system 24 00:00:49.750 --> 00:00:51.990 line:15% that might be worth trying to observe. 25 00:00:51.990 --> 00:00:53.430 It's known as Comet Leonard 26 00:00:53.430 --> 00:00:56.270 line:15% and it'll be at its closest to Earth on December 12th, 27 00:00:56.270 --> 00:00:58.140 line:15% just a couple of weeks before it reaches 28 00:00:58.140 --> 00:01:00.650 line:15% its closest distance from the Sun. 29 00:01:00.650 --> 00:01:03.310 Now comets are notoriously difficult to predict 30 00:01:03.310 --> 00:01:05.500 in terms of brightness and visibility. 31 00:01:05.500 --> 00:01:07.950 line:15% Comet Leonard is predicted to peak at a brightness 32 00:01:07.950 --> 00:01:11.040 line:15% that will probably require binoculars to spot it. 33 00:01:11.040 --> 00:01:12.510 There's a chance it could be bright enough 34 00:01:12.510 --> 00:01:14.070 to see with the unaided eye, 35 00:01:14.070 --> 00:01:16.960 but again, with comets you really never know. 36 00:01:16.960 --> 00:01:18.790 line:15% In the first couple of weeks of December, 37 00:01:18.790 --> 00:01:22.080 line:15% Comet Leonard can be found in the east before sunrise 38 00:01:22.080 --> 00:01:25.230 line:15% passing between Arcturus and the handle of the Big Dipper. 39 00:01:25.230 --> 00:01:27.270 line:15% It approaches the horizon right around the time 40 00:01:27.270 --> 00:01:28.700 line:15% of its closest approach to worth, 41 00:01:28.700 --> 00:01:30.200 line:15% meaning it'll likely be brighter, 42 00:01:30.200 --> 00:01:32.150 line:15% but more challenging to observe. 43 00:01:32.150 --> 00:01:34.360 line:15% It then switches over to being an evening object 44 00:01:34.360 --> 00:01:35.890 line:15% after around December 14th 45 00:01:35.890 --> 00:01:38.010 line:15% for just a little while after the sun sets, 46 00:01:38.010 --> 00:01:40.930 line:15% as it begins its long haul outward from the sun again, 47 00:01:40.930 --> 00:01:43.063 line:15% progressively fading in brightness. 48 00:01:43.063 --> 00:01:44.250 line:15% [Whoosh] 49 00:01:44.250 --> 00:01:45.830 Finally, the Geminid meteors 50 00:01:45.830 --> 00:01:48.450 are a highlight of December skies each year. 51 00:01:48.450 --> 00:01:50.240 line:15% This year's meteor shower peaks overnight 52 00:01:50.240 --> 00:01:52.350 line:15% on December 13th and 14th. 53 00:01:52.350 --> 00:01:53.350 Apart from the weather, 54 00:01:53.350 --> 00:01:55.500 the phase of the Moon is usually the main factor 55 00:01:55.500 --> 00:01:56.630 in whether a meteor shower 56 00:01:56.630 --> 00:01:58.910 will have good viewing any given year. 57 00:01:58.910 --> 00:02:01.500 This year, the Moon will be almost 80% full 58 00:02:01.500 --> 00:02:04.530 at the peak of the Geminids, which isn't ideal. 59 00:02:04.530 --> 00:02:07.480 However, that bright Moon will set somewhere around 2:00 AM, 60 00:02:07.480 --> 00:02:08.680 wherever you're located, 61 00:02:08.680 --> 00:02:12.170 leaving a couple of hours for meteor watching before dawn. 62 00:02:12.170 --> 00:02:15.330 line:15% The meteors appear to radiate from the constellation Gemini, 63 00:02:15.330 --> 00:02:17.510 line:15% which you'll find high in the west. 64 00:02:17.510 --> 00:02:19.960 Now while most annual meteor showers are caused 65 00:02:19.960 --> 00:02:21.580 by Earth passing through trails 66 00:02:21.580 --> 00:02:24.260 of dust-sized particles of comet debris. 67 00:02:24.260 --> 00:02:26.170 The Geminids are one of the few meteor showers 68 00:02:26.170 --> 00:02:28.070 that are caused by debris from an asteroid 69 00:02:28.070 --> 00:02:29.480 that crosses Earth's orbit. 70 00:02:29.480 --> 00:02:31.970 In this case, one called Phaethon. 71 00:02:31.970 --> 00:02:34.110 Recently NASA scientists shared findings 72 00:02:34.110 --> 00:02:36.770 that suggest the difference between an asteroid and a comet 73 00:02:36.770 --> 00:02:38.900 might be less clear than we realized. 74 00:02:38.900 --> 00:02:41.060 With fizzing sodium on Phaethon 75 00:02:41.060 --> 00:02:44.580 playing the same role as vaporizing ice on comets. 76 00:02:44.580 --> 00:02:46.720 And whether you catch a glimpse of Comet Leonard 77 00:02:46.720 --> 00:02:48.800 or meteors from asteroid Phaethon, 78 00:02:48.800 --> 00:02:50.870 both are reminders of the deep connections 79 00:02:50.870 --> 00:02:53.070 between Earth and the rest of the solar system 80 00:02:53.070 --> 00:02:56.193 that we discover because we look outward and we explore. 81 00:02:57.870 --> 00:03:00.120 Here are the phases of the Moon for December. 82 00:03:03.060 --> 00:03:05.020 You can catch up on all of NASA's missions 83 00:03:05.020 --> 00:03:08.610 to explore the solar system and beyond at nasa.gov. 84 00:03:08.610 --> 00:03:11.440 I'm Preston Dyches from NASA's Jet Propulsion Laboratory. 85 00:03:11.440 --> 00:03:13.240 And that's What's Up for this month.