The Night Sky This Month – October 2020

The Milky Way as seen in late summer and early autumn from the northern hemisphere.

October is a lovely month for stargazing, and the skies this October are especially eventful. The ‘Harvest Moon’ leads off the month, the first October Harvest Moon in 46 years. Mars makes its closest approach to Earth and its finest apparition of for the next 15 years. Best of all in October, you can get in a good night of stargazing without staying up too late. Add in a couple of meteor showers, a ‘Blue Moon’, the lingering arc of the Milky Way, and you’re in for some good stargazing. Here’s what to see in the night sky this month…

1 October 2020. Full Moon, 21:05 UT. This is a rare October ‘Harvest Moon’, the full Moon closest to the first day of autumn in the northern hemisphere. It’s the first October Harvest Moon in 46 years. Because the Moon lies near apogee, its also one of the smallest full Moons of the year.

Venus makes a close approach to Regulus in the eastern pre-dawn sky on October 2-3, 2020.

2-3 Oct. Venus continues its splendid apparition in the eastern sky before dawn. Today it has company and at 0h UT (Universal Time), the planet passes just 5 arc-minutes from the first-magnitude star Regulus. This closest approach lines up well for European and African observers, but the rest of us will see a slightly wider separation later in the day. But it’s still a modestly spectacular conjunction as the planet appears about half a degree west and east of the star, respectively, on these two days.

6 Oct. Already spectacularly bright, the planet Mars, which reaches opposition next week, makes its closest approach to Earth.

6 Oct. If you can’t wait for the stars of northern winter to arrive, then wake up well before sunrise to behold Orion, Canis Major, Taurus, Auriga, and Gemini lined up from overhead down to the south. Today, the waning gibbous Moon joins the show near the star Aldebaran in the constellation Taurus.

8 Oct. The waning gibbous Moon lies very close to the star cluster Messier 35 in the constellation Gemini in the early morning hours. Grab a pair of binoculars and have a look.

8 Oct. The Draconid meteor shower peaks over the next few days. This meteor shower occurs each year when the Earth passes through a stream of debris left from periodic Comet Giacobini-Zinner. While it’s usually a spartan meteor shower, with just a handful of meteors visible each hour, the Draconids have flared up from time to time. In 1933 and 1946, observers reported thousands of meteors per hour, so this modest shower became a meteor storm. There was also a good show in 1988. There’s no word of a flare up this year, but if you’re out stargazing, take a look. You never know.

10 Oct. Last Quarter Moon, 00:40 UT.

The planet Mars in the constellation at opposition in Pisces at about 10 p.m. local time on October 13, 2020.

13 Oct. Mars reaches opposition tonight some 26 months after the disappointing opposition of 2018, a time when the planet was low in the sky for northern observers and cloaked in a planet-wide dust storm. This year Mars lies about 5 degrees north of the celestial equator in the constellation Pisces, perfectly placed for observers of all latitudes. This is the best Martian opposition this decade, and the best until 2035. Keen to get a good look at the Red Planet this time around? This detailed guide at Cosmic Pursuits is packed with practical information to help you get the best view of Mars this month.

14 Oct. Look to the east before sunrise to see brilliant Venus rising along with a very slender crescent Moon.

16 Oct. New Moon, 19:31 UT

A Orionid meteor. Image credit: Jeff Sullivan via Flickr.

21 Oct. The Orionid meteor shower peaks in the early morning hours. One of the finest of all meteor showers, the Orionids display about 20-40 fast-moving meteors per hour in dark sky. The radiant lies near the club of Orion, but meteors will be visible anywhere in the sky with the peak likely occurring between midnight and dawn. The Moon, just 5 days past new, stays out of the way this year and makes it easier to see the faintest meteors. Like the Eta Aquariid meteor shower in May, the Orionids are tiny pieces of Comet Halley that hit the upper atmosphere as the Earth passes through the comet’s debris field.

22 Oct. Look to the southwest after sunset to see the first-quarter Moon form a small triangle with Jupiter and Saturn. The two big planets are slowly turning westward for the year, but they have some life left in them and are well worth observing in a telescope. Jupiter still shines brightly at magnitude -2.2 while Saturn has faded to magnitude +0.6

23 Oct. First Quarter Moon, 13;23 UT

Uranus reaches opposition near the ‘head’ of the constellation Cetus on October 31, 2020.

31 Oct. On this Halloween night, Uranus reaches opposition and rises in the east as the Sun sets in the west. This big ice giant shines at magnitude +5.7, just at the edge of naked-eye visibility, with a disk that spans a tiny 3.8 arc-seconds. Tonight the planet lies about 18.8 astronomical units (2.8 billion kilometers) from Earth. Look for this blue-green planet just northwest of the head of Cetus, southeast of Aries, and some 5.5º northeast of the 4th-magnitude star Xi Ceti. The full Moon makes it a little harder to spot Uranus tonight but the planet remains visible through the rest of the month and year in this part of the sky.

31 Oct. Full Moon, 14:49 UT. This second full Moon of a month is sometimes called a ‘Blue Moon’, although its not typically any shade of blue.