Every week, SkyNews publishes a list of key events in the Canadian sky in This Week’s Sky. This series gives you all the latest news in Solar System movements, including where the planets are in our sky and Moon phases. From eclipses to meteor showers, This Week’s Sky keeps you updated on the best in upcoming astronomical highlights.
Tuesday, March 15 – Moon occults Eta Leonis (after 7:55 p.m. EDT)
On Tuesday, March 15, observers in eastern North America and northwestern Africa can see the nearly full Moon cross in front of, or occult, the bright, magnitude 3.45 star named Eta Leonis and Algeiba, in Leo. Surrounding regions will see the Moon pass very close to the star. Occultations of bright stars can be watched through backyard telescopes and binoculars. The start and end times for the event vary by location. Use an astronomy app like Starry Night to look up the times for your site. In Montreal, the unlit leading edge of the Moon will cover the star at 7:56 p.m. EDT (or 23:56 UTC). Eta Leonis will pop out from behind the bright, trailing edge of the Moon, near Mare Crisium, at 9:04 p.m. EDT (or 01:04 UTC on March 16). For best results, start watching several minutes ahead of each of the times quoted.
Wednesday, March 16 – Venus closest to Mars (pre-dawn)
In the lower part of the southeastern sky before dawn on Wednesday, March 16, extremely bright Venus and much fainter Mars will reach their minimum separation of 3.9 degrees, making a nice photo opportunity. That’s more than close enough for them to share the field of view in binoculars (green circle). Mars will be positioned several finger widths to the lower right (celestial south) of Venus. The two planets will be nearly as close on the surrounding mornings. After Wednesday, Venus’ swing sunward will steadily increase its distance from Mars.
Thursday, March 17 – Comparing the Twins (evening)
While the Moon is bright and the planets are absent, skywatchers can still enjoy viewing bright stars. The twin stars of Gemini, Castor and Pollux, shine high in the southwestern sky after dusk. A closer look with your unaided eyes or binoculars (green circle) will reveal that the twins are quite dissimilar. The left-hand (easterly) star Pollux is nearly twice as bright as sibling Castor to its right (west). Pollux’ K0 spectral class gives it a warmer colour than does white, A1-class Castor. In a backyard telescope Castor is revealed to be a delightful multiple star system, with several fainter companions distributed around a bright, close-together pair.
Friday, March 18 – Full Moon (at 07:18 UTC)
The March full Moon will occur on Friday, March 18 at 3:18 a.m. EDT (or 07:18 UTC), causing it to appear full in the Americas on both Thursday night and Friday night. The March full Moon, known as the Worm Moon, Crow Moon, Sap Moon or Lenten Moon, always shines in or near the stars of Leo or Virgo. The Indigenous Ojibwe people of the Great Lakes region call the March full Moon Ziissbaakdoke-giizis, “Sugar Moon,” or Onaabani-giizis, the “Hard Crust on the Snow Moon,” signifying a time to balance our lives and to celebrate the new year. The Cree of North America call it Mikisiwipisim, the “the Eagle Moon” — the month when the eagle returns. The Cherokee call it Anvyi, the “Windy Moon,” when the planting cycle begins anew. Full moons always rise in the east as the Sun sets, and set in the west at sunrise. When fully illuminated, the Moon’s geology is enhanced, especially the contrast between the ancient cratered highlands and the younger smoother maria.
Saturday, March 19 – Full Moon occults Porrima (after 04:52 UTC)
In the wee hours of Saturday, March 19, observers in northeastern North America and the North Atlantic can see the full Moon cross in front of, or occult, the bright, magnitude 3.4 double star named Gamma Virginis and Porrima, in Virgo. Surrounding regions will see the Moon pass very close to the star. Occultations of bright stars can be watched through backyard telescopes and binoculars. The start and end times for the event vary by location. Use an astronomy app like Starry Night to look up the times for your site. In Halifax, Nova Scotia, the bright, leading edge of the Moon will cover the two stars at 1:52 a.m. EDT (or 04:52 UTC on March 20). Porrima’s pair will pop out from behind the darkened, trailing edge of the Moon, near Mare Fecunditatis, at 3:05 a.m. EDT (or 06:05 UTC on March 20). For best results, start watching several minutes ahead of each of the times quoted.
Sunday, March 20 – Venus at greatest western elongation (predawn)
On Sunday, March 20, Venus will reach its maximum angle from the Sun for the current appearance – 46.5 degrees west. At that time the planet will shine at a brilliant magnitude -4.5 in the lower part of the southeastern sky for about 90 minutes before sunrise. Viewed in a telescope (inset), the planet will exhibit a half-illuminated phase and an apparent disk diameter of 24.6 arc-seconds. Mars and Saturn will shine nearby.
Sunday, March 20 – March Equinox (at 15:33 UTC)
On Sunday, March 20 at 11:33 a.m. EDT (or 15:33 UTC) the Sun will cross the celestial equator traveling north, marking the vernal equinox in the Northern Hemisphere and the beginning of northern spring. Days and nights will be of equal length on that day, and the Sun will rise due east and set due west. At mid-northern latitudes on the March Equinox, the amount of daylight added to each day reaches its maximum of 3 minutes.
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 AstroGeo.ca to tour the Universe together.