12 Must-See Skywatching Events in 2012

The top 12 "skylights" for this coming year include a "double planet" in May and a Venus transit of the sun in June 2012.

By Joe Rao 

As the year 2011 comes to a close, some might wonder what is looming sky-wise for 2012? What celestial events might we look forward to seeing? 

I've selected what I consider to be the top 12 "skylights" for this coming year, and list them here in chronological order. Not all these events will be visible from any one locality … for the eclipses, for instance, you'll probably have to do some traveling … but many can be observed from the comfort of your backyard.

Hopefully your local weather will cooperate on most, if not all, of these dates. Clear skies!

Jan. 4: Quadrantid meteor shower peaks

This meteor shower reaches its peak in the predawn hours of Jan. 4 for eastern North America. The Quadrantid meteor shower is a very short-lived meteor display, whose peak rates only last several hours. The phase of the moon is a bright waxing gibbous, normally prohibitive for viewing any meteor shower, but the moon will set by 3 a.m., leaving the sky dark for a few hours until the first light of dawn; that's when you'll have the best shot at seeing many of these bluish-hued meteors. 

From the eastern half of North America, a single observer might count on seeing as many as 50-to-100 "Quads" in a single hour. From the western half of the continent the display will be on the wane by the time the moon sets, with hourly rates probably diminishing to around 25 to 50 meteors.

Feb. 20 to March 12: Best evening apparition of Mercury

In February and March, the "elusive" innermost planet Mercury moves far enough from the glare of the sun to be readily visible soon after sunset. Its appearance will be augmented by two other bright planets (Venus and Jupiter), which also will be visible in the western sky during this same time frame.

Mercury will arrive at its greatest elongation from the sun March 5. It will be quite bright (-1.3-to-0 magnitude) before this date and will fade rapidly to +1.6 magnitude thereafter. Astronomers measure the brightness of objects in terms of magnitude, with lower numbers corresponding to brighter objects.

March 3: Mars arrives at opposition

On March 3, the Earth will be passing Mars as the two planets wheel around the sun in their respective orbits. Because Mars reaches aphelion — its farthest point from the sun — on Feb. 15, this particular opposition will be an unfavorable one. In fact, two days after opposition, Mars will be closest to Earth at a distance of 62.6 million miles.

Compare this with the August 2003 opposition when Mars was only 34.6 million miles away.  Nonetheless, even at this unfavorable opposition the fiery-hued Mars will be an imposing naked-eye sight, shining at magnitude -1.2, just a bit dimmer than Sirius, the brightest star, and will be visible in the sky all night long.    

March 13: Brilliant "double planet"

The two brightest planets, Venus and Jupiter, team up to make for an eye-catching sight in the western sky soon after sunset. They will be separated by 3 degrees on this evening, Venus passing to the northwest (upper right) of Jupiter and shining nearly eight times brighter than "Big Jupe." Although they will gradually go their separate ways after this date, on March 25 and 26,