Southern Colorado Skies / December 10-16, 2017

Consider a planetarium program to help you plan your observations. There are many commercial products available; an excellent program (STELLARIUM) is available free at


The Moon comes within a couple degrees of Mars on December 13, and then (as a bonus) comes within a couple degrees of Jupiter on the 14th. (Not sure what that “M” object is? Check out my short article at

Wednesday (December 13)

Early in the morning look for the waning crescent Moon just above faint Mars by a couple degrees. as shown in the above graphic. Spica, a bit brighter than Mars, may be found to the right (west) of the Moon as shown.

The Geminid meteor shower, often called the best meteor shower of the year, should be reaching its peak tonight, and – good news – the Moon will not be around to “wash out” the sky.

Look toward the constellation Gemini, as the meteors will appear to radiate from that location. The Geminids are famous for “Earth-grazing” meteors that enter the atmosphere at a shallow angle just after dusk on the night of the 13th, and therefore seem to originate at or from below the horizon. About 120 meteors per hour are predicted at the shower’s maximum, which occurs when the radiant (Gemini) is due south about 2:00 a.m. (after midnight the Earth is turning into the shower, which makes this the best time to view any meteor shower).

Friday (December 15)

Before dawn look for an alignment of the crescent Moon, Jupiter, Mars, and Spica (from bottom to top, as shown above). PA photo opportunity?




Mercury (in Ophiuchus), Venus (in Ophiuchus), and Saturn (in Sagittarius)

Lost in the glare of the Sun this week.

Mars (in Virgo), and Jupiter (in Libra)

Look for both planets rising before dawn in the east-southeast. By dawn they are both well up in the southeastern sky (see above graphic).

Uranus (in Pisces):

Look high in the southeast by early evening.

Neptune (in Aquarius):

Look high in the south by early evening.


The following data are based on my location in Pueblo West, Colorado. If you live well outside this area, you should consider checking this information for your location in order to be assured of accurate times, elevations, etc. If you’re unfamiliar with Iridium flares, check out my short article at:

Monday (December 11) 6:59:00 a.m. / Magnitude -8.2 / NNW / Elevation 73 degrees

Monday (December 11) 6:27:34 p.m. / Magnitude -1.3 / S / Elevation 29 degrees

Tuesday (December 12) 6:52:58 a.m. / Magnitude -3.4 / NNW / Elevation 72 degrees

Tuesday (December 12) 6:21:33 p.m. / Magnitude -1.0 / S / Elevation 29 degrees

Wednesday (December 13) 5:40:06 p.m. / Magnitude -2.7 / W / Elevation 12 degrees

Wednesday (December 13) 6:15:30 p.m. / Magnitude -5.0 / S / Elevation 29 degrees

Thursday (December 14) 5:25:06 p.m. / Magnitude -5.5 / W / Elevation 15 degrees

Friday (December 15) 4:46:oo p.m. / Magnitude -5.4 / SW / Elevation 17 degrees

Friday (December 15) 5:10:05 p.m. / Magnitude -1.4 / W / Elevation 19 degrees

Saturday (December 16) 5:04:12 p.m. / Magnitude -5.7 / W / Elevation 19 degrees


These are too numerous to list here! If you’re seriously interested, load the ISS DETECTOR app on your smart phone or tablet.

Carpe noctem

Dave Furry

Pueblo West, Colorado

Leave a Reply