Space Science at UTK

Cool Things in the Sky

Cool Things

For the month of December 2017

The Geminid Meteors will race across our skies this month but peak activity is on the night of the 13th and morning of the 14th. The source of the Geminids is an asteroid (and sometimes called a rock comet) named 3200 Phaethon. Its orbit brings it close enough to the sun every 524 days to heat the 3 mile wide rock sufficiently to cause the surface to fracture and leave behind bits of rocky particles. As usual, find a dark location, lie on the ground feet pointed south and enjoy the show. If the weather is good this could be the best shower of the year with about 120 meteors per hour.


Venus dips too close to the sun very early this month in the morning sky.


Mercury and Saturn are chasing the setting sun this month and very low in the west at sunset.


Look for reddish Mars about 30 degrees above the East-southeastern horizon with yellowish Jupiter about 10 degrees below around 7:30 AM. Look for a waning crescent moon to join these two on the morning of the 14th along with a few meteors.


The moon phases for this month are full on the 3rd, last quarter on the 10th, new on the 18th and first quarter on the 26th.