Mars poised for invasion as the Red Planet gets close
Meteor showers, Mars and winter constellations make for some great but chilly starwatching in December.
If you see something red in the sky, it might not be Rudolph.
Mars has invaded our eastern evening sky and is less than 52 million miles away. This is as closest Mars and Earth have been to each other in over two years, meaning the second-brightest star-like object in the evening sky this month — only Jupiter in the western half of the sky is brighter — will be just a little brighter.
Thursday, Dec. 8, the Earth and Mars will be in what astronomers call opposition, meaning Mars and the sun are on opposite sides of the sky. Just like a full moon, Mars rises at sunset and sets at sunrise so it’s available for viewing all night long. Speaking of a full moon, that’s what we’ll see Wednesday, Dec. 7, and that same evening the moon will cross in front of Mars, eclipsing the red planet, what astronomers call an opposition. This is a must-see event. A small telescope or even a pair of binoculars will make it even sweeter.
During evening twilight Wednesday evening Mars and the moon will rise really close to each other in the eastern sky. Mars will be just to lower left of the moon. As early evening progress the full moon will draw closer and closer to Mars until around 9:03 p.m. Mars will disappear behind the lunar disk and reappear at the right edge of the moon just after 10:10 p.m.
Unfortunately that same full moon will spoil the annual Geminid meteor shower Dec. 13-14, one of the best of the year, as there interfering moonlight will persist with the waning gibbous moon rising around 9 p.m. Despite that, the Geminids are such a prolific shower you should be able to catch at least some meteors, especially away from light pollution in the countryside.
Later this month, there will be another meteor shower, the Ursids, peaking the night of Dec. 21-22. There won’t be any competing moonlight, but this is a minor meteor shower producing only around 10 to 15 meteors an hour. It’s still worth a look-see.
December nights are blessed with some of the brightest constellations of the year, more than worth bundling up in order to catch a glimpse. The great horse Pegasus is riding high in the south-southwestern sky with Cassiopeia the Queen, looking like a bright “W” in the high northern sky. The Big Dipper, the rear end and tail of the constellation Ursa Major, or Big Bear, is still very low in the early evening northern sky. The Little Dipper, otherwise known as Ursa Minor, the Little Bear, is hanging by its handle above the Big Dipper. The North Star is at the end of its handle. Because Polaris shines directly above Earth’s North Pole, it appears that all the stars in the sky revolve around Polaris once every 24 hours, including our sun.
The later you stay up in the evening, the more you’ll see as the best part of the December skies rise in the east. By 8 to 9 p.m., you’ll see Orion the Hunter, the wonderful winter constellation, proudly showing off its bright stars. Its calling card is the three bright stars in a row that make Orion’s belt. The bright constellation Taurus the Bull, with the great Pleiades star cluster, precedes Orion. Just north of Orion is the constellation Gemini the Twins, with the bright stars Castor and Pollux that mark the heads of twin half-brothers Castor and Pollux. I call this part of the sky “Orion and his gang.”
Have a fun-filled and star-filled holiday season.
Mike Lynch is an amateur astronomer and professional broadcast meteorologist for WCCO Radio in Minneapolis/St. Paul and is author of the book, “Stars, a Month by Month Tour of the Constellations” published by Adventure Publications. Send questions to firstname.lastname@example.org .
The Rochester Astronomy Club welcomes new members and puts on public star parties. Their website is rochesterskies.org .