SCAS – Southern Colorado Skies / January 17 – 23, 2016

Consider a planetarium program to help you plan your observations. There are many commercial products available, and a very good program (Cartes du Ciel) is available free at

Atmospheric Conditions

Other than relying on the local news and hoping that “things will clear up in time,” what can you do to predict if it will be a good night for stargazing? Here are a couple important terms …

Transparency is a measure of how bright a star appears to be. A synonym may be “clarity.” Haze, smoke, smog or dust can reduce transparency, as will light pollution if you live in a city or are affected by neighborhood lights.

Seeing refers to the steadiness of an image. Heat and turbulence in the atmosphere are big factors in ‘seeing.’ The buildup of heat during the day can cause images to “boil” or otherwise deform when magnified through a telescope or binoculars. Turbulence is caused by layers of contrary air currents in the upper and lower atmosphere. The good news is that lower-level turbulence usually dissipates by midnight (if you can manage to stay up that late!).

There are a couple apps that I recommend (we will be discussing other astronomy apps at this Thursday’s SCAS meeting). The first app I recommend is actually a computer application from Allan Rahill of the Canadian Meteorological Center ( There are pre-established viewing locations to choose from all over Canada and the U.S. As you can see, a full two-day forecast is provided, including cloud cover, wind, humidity and temperature. The color coding is explained on the web site.


Another useful app for phones and tablets is called “Astro-Panel.” It’s available at the Google Play Store (I am an android user – I presume it’s available for you apple users as well). The same sort of information is provided as above, but in a slightly different format.



Monday (January 18)

Callisto, the outermost Galilean moon of Jupiter, is eclipsed by the giant planet’s shadow Jupiter’s about 10:32 this evening.

Tuesday (January 19)

The waxing gibbous (82 percent sunlit) Moon occults (comes in front of) Aldebaran tonight beginning at about 6:30 p.m. MST. The occultation will start on the dark limb of the Moon and end as Aldebaran reappears on the sunlit side about an hour later. This should be easy enough to watch with the naked eye, binoculars or a telescope.

Saturday (January 23)

Full Moon at 6:46 p.m. MST. Pollux and Castor (Gemini) will appear above and little to the left of the Moon, and Procyon (Canis Minor) will be below and little to its right.


Mercury (in Sagittarius)

Lost in the Sun’s glare. Make a note – on May 9th this year Mercury will transit part of the Sun for the first time since 2006.

Venus and Saturn (in Ophiuchus)

These two planets remain pretty close to each other all week, but Venus is getting lower as Saturn rises higher in the sky. Look for them in the east just before dawn.

Mars (in Virgo)

High in the south at dawn.

Jupiter (in Leo/Virgo)

Rises about 10 p.m., highest about 3:30 a.m., and in the southwestern sky at dawn.

Uranus (in Pisces)

High in the southwest sky by early evening.

Neptune (in Aquarius)

Getting lower in the west-southwestern sky in early evening.

Iridium Flares and International Space Station (ISS)

Sorry – these are too numerous to list here! If you’re serious, load the ISS DETECTOR app on your smart phone or tablet. Alternatively, refer to SCAS member Chuck Percival’s column in the Sunday Pueblo Chieftain.

Have fun!

Dave Furry, SCAS Director of Education

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