Archive for March 4, 2021

03/04/2021 – Ephemeris – A very crabby constellation

March 4, 2021 Comments off

Mar 4. This is Ephemeris for Thursday, March 4th. Today the Sun will be up for 11 hours and 20 minutes, setting at 6:34, and it will rise tomorrow at 7:12. The Moon, 1 day before last quarter, will rise at 1:26 tomorrow morning.

Lying between the stars Castor and Pollux in Gemini high in the southeast and the star Regulus in Leo the Lion in the east-southeast is the dimmest constellation of the zodiac, Cancer the crab. To me its 5 brightest stars make an upside down Y. There are the stars in the center of the constellation Asellus Borealis and Asellus Australis, the north and south donkeys. There’s a fuzzy spot between and just west of them called Praesepe, the manger from which they are supposedly eating. In binoculars, it resolves into a cluster of stars called the Beehive star cluster. We amateur astronomers also know it as M 44, the 44th object on 18th century comet hunter Charles Messier’s list of fuzzy objects that might be mistaken for comets.

The astronomical event times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.



The constellation Cancer finder chart. Created using Cartes du Ciel (Sky Charts).

The Beehive

The Beehive star cluster, M44. Its ancient name was the Praesepe or manger when glimpsed by the naked eye. Created using Cartes du Ciel (Sky Charts)

Note in the top image above the star cluster M 67 at the bottom of Cancer, near the star Acubens. M 67 requires a small telescope to spot. They are both open or galactic star clusters which lie in or very near the plane of the Milky Way, denoted by the milky band. Part of the milky band can be seen at the upper right of the chart. M 44 is quite close to us, at only 610 light years away so is physically close to the plane of the Milky Way. M67, however is 2,610 to 2,930 light years away and is quite a bit farther than M 44 from the plane of the Milky Way. It is also much older (4 billion years old) than the stars of the Beehive (600 to 700 years old).

M67 photograph

M67 is a beautiful telescopic object. Credit Nigel Sharp, Mark Hanna, AURA/NOAO/NSF.