The Night Sky This Month – January 2020
Happy new year! The first month of 2020 begins with the brief but often spectacular Quadrantid meteor shower, which can on a good year produce about 100 meteors an hour near its peak. A partial lunar eclipse takes place for observers in Europe and Africa. Mars cruises through the constellation Scorpius in the pre-dawn sky, while Jupiter emerges from the Sun’s glare. And Venus and Neptune are just a hair’s width apart at the end of the month, offering observers with a small telescope a chance to see these two worlds in a single field of view. Here’s what’s up in the night sky this month.
22 December 2019. The Sun reaches the December Solstice, the southernmost point on the ecliptic at 04:19 UTC. This marks the longest night of the year in the northern hemisphere and the longest day of the year in the southern hemisphere. Happy Winter and Summer, respectively!
26 December 2019. New Moon, 5:13 UT
27-29 December 2019. Look for a slender crescent Moon along with bright Venus and fainter (and much lower) Saturn in the southwestern sky after just after sunset.
3 January 2020. First Quarter Moon, 04:45 UTC.
3-4 Jan. The early morning of January 4 features a brief but sometimes spectacular meteor shower. Named after the now-defunct northern constellation Quadrans Muralis, the Quadrantids can feature more than 100 meteors per hour. Conditions are favorable this year as the first-quarter Moon sets around 1 a.m. local time. The meteors will peak near 2-3 a.m., and you can see them anywhere in the sky. They trace their paths back to a point north of the bright star Arcturus which rises in the northeast in the pre-dawn hours.
5 Jan. Earth reaches perihelion, its closest point to the Sun in its orbit. At a distance to the Sun of 147,091,144 km, our planet is about 3% closer than aphelion, its furthest point from the Sun, which occurs in July.
8 Jan. Look for the waxing gibbous Moon just one degree from the 3rd-magnitude star zeta Tauri in the horns of the constellation Taurus, the Bull.
10 Jan. Full Moon, 19:21 UTC
10 Jan. The Moon undergoes a partial eclipse as it passes into the penumbra, the outer reaches of the Earth’s shadow. The event is visible in most of Europe, Africa, and Asia. The time of greatest eclipse is 19:10 UTC, and the event begins and ends about two hours before and after this time.
10 Jan. Mercury is in superior conjunction and lost in the Sun’s glare until later this month.
13 Jan. Saturn lies in conjunction with the Sun and find itself lost in the Sun’s glare. It re-emerges into the dawn sky later this month.
17 Jan. Last Quarter Moon, 12:58 UTC
20 Jan. The waning crescent Moon makes a lovely triangle with the bright star Antares and the planet Mars in the southeastern sky before dawn. Mars is slightly fainter than Antares, but the two are remarkably similar in color. Antares is named for Mars: its name means “against or compared to Ares”, another name for Mars, the Roman god of war. Mars slowly brightens throughout the year on its way to a splendid opposition in October 2020.
22 Jan. Look closely to the southeast before dawn for a very slender crescent Moon with Jupiter rising about three finger-widths (6o) to the east. Jupiter has just emerged into the morning sky and is still relatively distant. Still, at magnitude -1.9, it outshines every star in the sky.
24 Jan. New Moon, 21:42 UTC
27 Jan. The Moon returns to the evening sky and appears just 6o from brilliant Venus in the west after sunset. Today, the planet Neptune is less than 0.25 degrees north of Venus. If you have a telescope, try to see these two worlds in a single field of view. As January ends, Venus rises nearly 3.5 hours after the Sun and reaches well above the western horizon at sunset. Other than the Moon or Sun, it’s the brightest thing in the sky.