Graphic courtesy of Andy Veh
The diagram depicts the sky around 10 p.m. early in the month and 8 to 9 p.m. in the middle of March, which is actually only one hour after sunset. Toward the end of the month more of the now-eastern constellations will be visible and fewer of the western. I also outlined a few prominent constellations and labeled them with three letter abbreviations as well as the brightest stars with a capital letter. Throughout the text and the diagram, look for some special objects visible with binoculars (the darker your observing site, the better), labeled with lower-case letters.
Three planets can be seen in the evening this month. Saturn finally relinquishes its dominance, though due to its proximity to Castor and Pollux in Gemini, it's easy to find. Jupiter rises between 9 and 10 p.m. You won't be able to miss it because during spring it'll be the brightest object in the night sky apart from our moon.
The diagram shows specifically the evening of March 11 where Mercury, the elusive inner planet, can be seen most easily because the thin sliver of our moon is right next to it. Mercury is otherwise hard to find because it's only visible very low on the horizon during twilight. During this month's apparition there are no other bright stars close by that could point to it. You can try to find Mercury the week preceding March 11 when it shows as a lonely point in the deep blue sky and during the following week when our waxing moon helps point it out (note, though, that the moon will reach Saturn by March 19. Since Mercury orbits so quickly in only 87 days around our sun, it's only visible in a favorable position for a week or two at a time, like during the evening this year in March, July and November and during the morning this year in April, August and December.
As far as the stars go, find Orion the hunter with red Betelgeuse and blue Rigel in the southwest with the "Orion nebula" (I put these in quotes and use lower case letters on the map to point them out as objects for binoculars) beneath the belt. To its lower left is Sirius, the brightest star in the sky, then Procyon and Castor and Pollux, the twin stars, to its upper left. Finally, the arrow-shaped snout of the bull Taurus with reddish Aldebaran including the star clusters "Hyades" and "Pleiades" are above Orion. Yellow Capella in its pentagon of Auriga is almost overhead, which hosts three "open clusters." The visitor among these bright stars of winter is Saturn, forming an obtuse triangle with Castor and Pollux.
Other bright stars that are visible in the night sky include Leo's Regulus high in the southeast. The lion appearing in the evening means that spring is right around the corner. There's also the faint constellation of Cancer between Saturn and Regulus, which hosts the pretty star cluster Praesepe or "Beehive" and the yellow and blue double stars "iota." Skimming the northern horizon there is Arcturus in Bootes in the northeast, easily found because the Big Dipper's handle curves toward it, as well as Lyra's Vega and Cygnus' Deneb (the Swan or Northern Cross) in the north with the globular "Hercules cluster" nearby.
To conclude this tour, find the Great Square of Pegasus in the west with the "Andromeda Galaxy." High in the sky are the three circumpolar constellations Cassiopeia, the Queen, visible as a small W, and Ursa Major and Minor, also known as the Big Dipper and Little Dipper with the double stars "Mizar and Alcor" in the bend of the Big Dipper's handle and "Comet Machholz" near Polaris.
Just beneath the lower left portion of Cassiopeia's W is the double cluster in Perseus. The comet is so high that I recently had a young man in my astronomy class lying down in the snow so he wouldn't have to crane his neck to see it. He found the comet relatively easily.
Note that globular clusters, galaxies, nebulae and comets all appear somewhat smudgy with binoculars and small telescopes. The pictures you see published are long-time exposures taken through larger telescopes that are able to show much more detail.
Andy Veh is the physics and astronomy instructor at Kenai Peninsula College. This column appears on the first Sunday of each month. He can be reached at firstname.lastname@example.org.
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