Weekly astronomy blog for the week ending December 31, 2011
The new year starts with a first quarter moon. It thickens up a little bit as it passes 5 degrees north of Jupiter two days later. Then, nearly full, the moon will be nearly 6 degrees north of Aldebaran on the 6th. It’ll be full when it’s 10 degrees south of Pollux on the 9th, waning just a little when it’s almost 6 degrees south of Regulus on the 12th, and more visibly waning 9 degrees south of Mars on the 14th. A last quarter moon will be 2 degrees south of Spica and more than 6 degrees south of Saturn on the 16th. Antares will be 4 degrees north of the waning crescent on the 19th. And there won’t be much of a crescent left when Mercury is almost 5 degrees north of it in the dawn’s light on the 22nd. A Venus-Moon pairup happens in our evening sky on the 26th. There’s another Moon-Jupiter pairup on the 30th.
January is regarded in the northern hemisphere as a great month for beginning stargazers. The nights are long and start early. And winter constellations are fairly bright and easy to recognize. Chances are, you can find Orion easily. Learn a little about the stars in Orion and a few nights later you can start finding your way to other constellations nearby. Orion is rising at sunset and stays up almost all night.
A little above Orion in the evening (to the west), you’ll see a V shaped arrangement of stars. One of the stars is bright orange. That group is called the Hyades. A little further west and you’ll find the Pleiades, looking like a kite or a lowercase Y. Below Orion (to the east) are the twins, Gemini.
Venus is the bright object setting not long after sunset this month. It’s staying up later and later throughout the month. Almost on the meridian at sunset is Jupiter, another very bright object.
Late in the evening, you’ll find ruddy Mars near a triangle of stars in the tail of Leo the lion. A little later than that, Saturn rises. In the early days of January, you might find Mercury in the morning sky.
Earth will be at perihelion, closest to the sun, on the 5th. People in the middle and high northern hemisphere latitudes, who usually find January to be the coldest month, sometimes think the planet is farthest from the sun at this time. However, the angle at which the sun shines on you has more to do with how warm or cold it is than how far away it is.
If you’re hoping for a meteor shower to start the new year, wait just a few days after 2012 starts. The Quadrantid meteor shower is expected to put on a brief show. NASA says it’s such a brief show, you’ll either see it early in the morning of January 4 or you won’t see it at all. This is a northern hemisphere meteor shower. If 2012 turns out to be a good year for them, you may see them at a rate of one or two a minute.