Full Beaver Moon and penumbral lunar eclipse (Chris Vaughan, Starry Night Education)

This Week’s Sky: November 30 to December 6, 2020

The week starts off with a penumbral lunar eclipse, then keep your eyes on the Moon over the next few days as it crosses Messier 35 and passes Messier 44.

Monday, November 30 – Full Beaver Moon and penumbral lunar eclipse (maximum at 9:44 GMT)

Full Beaver Moon and penumbral lunar eclipse (Chris Vaughan, Starry Night Education)

The November Full Moon, traditionally known as the Beaver Moon or Frost Moon, always shines in or near the stars of Taurus and Aries. Full moons occurring during the winter months in North America will climb as high in the sky as the summer noonday Sun, and cast similar shadows. This full Moon’s orbital motion (green line) will carry it into Earth’s outer shadow, producing a penumbral eclipse that will be visible in its entirety across most of North and Central America as well as northern Asia. The Moon will first contact the shadow at 07:32:22 GMT. At greatest eclipse at 09:44:02 GMT, approximately 83 per cent of the Moon’s disk will be within the Earth’s southern penumbral shadow. The subtle darkening of the Moon’s right-hand (northern) limb will be visible only within about 30 minutes of greatest eclipse. The eclipse will end at 11:53:26 GMT. South America and northern Europe will only see the early stages, while Australia, southeast Asia, China and parts of Russia will only see the latter stages.

Tuesday, December 1 – Bright Moon crosses Messier 35 (overnight)

Between the evening of Tuesday, December 1 and the following morning, observers in most of North America will see the orbital motion (green line) of the waning gibbous Moon carry it in front of a large open star cluster in Gemini known as Messier 35, or the Shoe-Buckle Cluster. While the Moon climbs the eastern sky during Tuesday evening, it will be slowly approaching the cluster from the celestial west. To best see Messier 35’s stars at that time, wait until they are higher in mid-evening, and then hide the bright Moon beyond the upper right edge of your binoculars (red circle). The Moon will obscure all or part of the cluster for about two hours centered on 3:40 a.m. Eastern Standard Time (or 8:40 GMT), and then it will depart from the cluster’s upper left (or celestial east) edge while both objects descend in the western sky.

Friday, December 4 – Moon and the Beehive (overnight)

When the waning gibbous Moon rises in the eastern sky in late evening on Friday, December 4, it will positioned only two finger widths to the left (or 2 degrees to the celestial north) of the large open star cluster in Cancer known as the Beehive, or Messier 44. The cluster, which contains at least 1,000 stars, extends for two full Moon diameters across the sky. The Moon and the cluster will fit together in the field of view of binoculars (red circle). During the rest of the night the Moon’s eastward orbital motion (green line) will carry it farther from the Beehive. To best see the cluster’s stars, hide the bright Moon just outside the left edge of your binoculars’ field of view.

Monday, December 7 – Moon near Asteroid Vesta (pre-dawn)

High in the southern pre-dawn sky on Monday, December 7, the waning gibbous Moon will be positioned a palm’s width to the upper right (or six degrees to the celestial west) of the magnitude 7.55 main belt asteroid Vesta in the constellation of Leo, the Lion. Though not visible from Canada, for about an hour centred on 21:00 GMT, observers in most of eastern and northern Europe, parts of Russia and China, Japan, northern Philippines and Micronesia can see the Moon cross in front of (or occult) Vesta.

Chris Vaughan is a science writer, geophysicist, astronomer, planetary scientist and an “outreach RASCal.” He writes Astronomy Skylights, and you can follow him on Twitter at @astrogeoguy. He can also bring his Digital Starlab portable inflatable planetarium to your school or other daytime or evening event. Contact him through to tour the universe together.