Astronomical Observing News (12/21 to 12/27)

This week's AON is brief, but there's plenty to see. Without adieu, here's the news:

• Through March 2012—The Garradd comet shines in the sky! Here's how to observe it!

• December 21, 2011—The moon is at its perigee (364,800 km from Earth).
• December 22, 2011—Winter solstice.
• December 23, 2011—There's a Mercury-moon conjunction. This means Mercury is at greatest elongation (22 degrees west of the sun), and the moon is at its most southern declination.
• December 24, 2011—Mercury and the bright star Antares conjure in the sky. This is interesting because Antares is a binary star system, meaning it had a companion star. Antares' companion star, which is called Antares B, is smaller than Antares, which means it rotates around Antares. If a companion star was the same size, they would rotate around each other.

Also, there's a new moon, which is fun to observe! If I missed anything, please post in the comments below.