WHITT COLUMN: The darkest month of the year
By Kelly Kizer-Whitt, Sauk Prairie Eagle columnist
In Wisconsin, December provides the shortest days and longest nights of any month.
Unfortunately for stargazers, it is often the cloudiest month as well.
The solstice occurs at 6:04 a.m. on December 21, bringing with it the first day of winter.
The sun will rise at approximately 7:30 a.m. and set at 4:30 p.m. during the solstice.
Venus, Jupiter, Mercury, and M75
The essential elements for observing this month are clear skies and a view to the west. On December 1, Venus, Jupiter, and a crescent moon will be gathered together in the southwest after sunset. Every night afterward, Venus climbs away from the horizon until it reaches its highest and brightest for the year. On December 6 and 7, use a pair of binoculars or a telescope to catch the globular cluster M75 about one degree away from Venus. At 8th magnitude, M75 can be hard to see. This grouping of thousands of stars lies about 67,500 light-years away on the edge of our galaxy and will appear as a fuzzy patch through optical instruments.
On Dec. 27, Venus comes within one and a half degrees of Neptune. Venus, the brightest star-like object in the sky, will be very close to the star Delta Capricorni on this night. On the opposite side of Venus from Delta is Neptune at magnitude 7.9; it will lie just below an arc of three dim stars. Use binoculars or a telescope to see the most distant planet from the sun.
Mercury bestows its presence on us the week of Christmas when it reappears above the western horizon. On December 28, a crescent moon, Mercury, and Jupiter follow the setting sun in a closely spaced line. The solar system's smallest planet, Mercury, and its largest, Jupiter, make their closest encounter on December 31, with Jupiter the slightly brighter of the two. This night also provides another opportunity to spot M75, as it is just a quarter of a degree from Mercury. On New Year's Eve the moon and Venus will also be a brilliant sight in the west. For those up past midnight, look for Saturn rising in the east.
Because the full moon occurs on December 12, the Geminid meteor shower, which peaks the next night, will be mostly a bust. A second meteor shower called the Ursids occurs on December 22, but it is less active than the Geminids.
Buying a telescope for Christmas
A telescope is often a tempting purchase at Christmas time. But the first steps for someone who wants to learn the night sky are to get a good pair of binoculars, a planisphere or star chart, and a book such as Nightwatch by Terrence Dickinson.
If you are set on a telescope, two good ones for beginners that are priced under $100 are the Bushnell 3-inch reflector or the Celestron ExploraScope 100.
Go-to scopes, such as Meade's Autostar, are very popular for beginners because after a short set up routine, the telescope will track down sky objects for you. But the price for this convenience is steep and once you learn the location of objects in the sky the go-to feature will be unnecessary.