This month, lots of merry and bright
December’s sky offers a goody bag full of fun: bright planets, shooting stars, a new season, more light — and perhaps a comet tossed in.
Venus starts December on a dazzling note at -4.9 magnitude. Throughout December, find the planet in the southeast before sunrise. You can’t miss it: It looks like a jetliner with its landing lights on.
On Dec. 3, enjoy the brilliant Venus beneath the sliver of a waning crescent moon, and on the following night, the thinner wisp of the crescent moon will be to the lower left of Venus.
By mid-month, the morning heavens offer the large gaseous Jupiter surfacing from a brief autumnal hiatus. Catch Jupiter later this week in the east-southeast peeking over the morning horizon to grab coffee with the fleet Mercury before sunrise. Jupiter, with a -1.7 magnitude (bright), gets higher in the morning sky, while Mercury is -0.4 magnitude (bright enough to find), according to U.S. Naval Observatory data.
Make sure you have a clear view of the east-southeast horizon, as Jupiter and Mercury dance a cosmic tango and nudge closer, so that by Dec. 21, the two planets appear less than a degree apart.
Evening planetary action starts in the western sky at dusk, when the ringed Saturn hangs low in the southwest after dark. The young, new crescent moon is found below Saturn on Dec. 8, but leapfrogs the ringed planet the next night.
Our red neighbor Mars saunters in the south at nightfall early in December. It’s a zero-magnitude object, bright enough to see, and chills in the constellation Aquariusnow. The nearly firstquarter moon appears to pass underneath the planet Dec. 14.
Comet Wirtanen (46P), a periodic comet passing through our neck of the solar system in mid-December, may approach naked-eye visibility for urban areas — but seeing it through binoculars may be a good choice. The University of Maryland has a website for updated detail: wirtanen.astro.umd.edu. The comet in the middle of the month may be found in the Taurus constellation, in the eastern sky in the early evening, and then in the western sky around 2 a.m., near the Pleiades (Messier 45), according to astronomer Geoff Chester of the Naval Observatory.
Zipping through the heavens, the Geminid meteors peak on the night of Dec. 13-14, at about 120 per hour, according to the American Meteor Society (amsmeteors.org). Normally comets can be tapped as the cause for shooting stars, but asteroid 3200 Phaethon prompted this show. (Journeying through the solar system, the comets leave dust behind when they round the sun. The Earth smacks into a comet’s dusty path and it lights up our atmosphere, giving us a meteor show.)
A few nights before Christmas, catch the sparse Ursid meteor shower, which peaks at 10 per hour Dec. 22-23, according to the society. The parent comet (8P/Tuttle) of these shooting stars was discovered by Horace Tuttle in 1858 at Harvard College Observatory in Cambridge, Mass. — years before he was a Naval Observatory astronomer.
Dark days will soon be behind us, as the winter solstice arrives Dec. 21 at 5:23 p.m., according to the Naval Observatory. Washington will have nine hours and 26 minutes of light that day — the least amount all year. On Jan. 1, we’ll see nine hours, 30 minutes. The good news for the next six months is that we’ll slowly gain more light. Down-to-Earth events:
Dec. 3 — Unwrap the gift of the night sky at “Stars Tonight” at the David M. Brown Planetarium, 1426 N. Quincy St., Arlington, adjacent to Washington-Lee High School. 7:30 p.m. $3. friendsoftheplanetarium.org.
Dec. 5 — Student astronomy research presentations at the University of Maryland’s Observatory open house, College Park. Following the presentations, tour the heavens through telescopes, weather permitting. 8 p.m. astro.umd.edu/openhouse.
Dec. 8 — “New Astronomy with Gravitational Waves,” a talk by University of Maryland physicist Peter Shawhan at the National Capital Astronomers’ regular meeting. The meeting is held at the University of Maryland Observatory, College Park. 7:30 p.m. capitalastronomers.org.
Dec. 20 — “Cosmic Dust Near and Far,” a talk by research astronomer Ludmilla Kolokolova at the University of Maryland’s Observatory, College Park. Enjoy the heavenly views of the night sky through telescopes, weather permitting. 8 p.m. astro.umd.edu/openhouse.
Dec. 21 — Accompany the new winter season at 5:23 p.m. with “The Day of the Sun’s Return: The Winter Solstice,” a program at the Montgomery College Planetarium, Takoma Park. 5 p.m. goo.gl/q9iwrS.