Greetings, stargazers.
I didn’t know Durango had a monsoon season in January, but that is certainly what it has felt like for the last week. There is nothing quite like some freezing rain to put a damper on night sky observations.
This is a good time to remind you about keeping your feet off the frozen ground if you do make it outside for some winter stargazing. Most people bundle up well enough, but if you are sitting on a nicely insulated cushion, your feet are typically still touching the ground. Because it will take at least 15 minutes for your eyes to get completely adjusted to the dark, staying warm while you are waiting is especially important.
A 1-inch thick scrap of Styrofoam to rest your feet on will prevent the heat from flowing out of them and into the frozen ground. Even with good snow boots, this trick will help keep your feet from getting too cold before your eyes have even adjusted to the dark.
The southeastern sky is dominated by easily recognizable Orion. The belt stars of Alnitak, Alnilam and Mintaka are positioned on the celestial equator so are an excellent indicator of east when Orion rises, and west when it sets.
Besides the belt, Orion is identified with the bright stars Betelgeuse and Rigel on opposite sides of the belt. I often use those two to point out differences in star color. Betelgeuse is similar in apparent brightness to Rigel but is noticeably redder in color.
Between the belt stars at Orion’s waist and Rigel at Orion’s foot is the cluster and nebula that make up Orion’s sword. Designated M42, this is one of the few nebulae visible to the naked eye and is one of the most rewarding objects to look at through binoculars or telescope.
Venus, still the brightest object in the sky after the moon, reaches its greatest eastern elongation tonight. This is the day it will be highest in the sky as the evening star. During the next few weeks, Venus will be moving between the Earth and the sun and taking on more of a crescent shape through a telescope. A crescent Venus, as first seen through a telescope by Galileo, was one of the significant facts supporting a heliocentric, rather than a geocentric, model for the solar system.
Mars is within 10 degrees, or about a one fist-width at arms-length above and to the left of Venus. During January, Mars and Venus will be getting closer to each other. On Jan. 31, the two planets and a crescent moon will be clustered within 5 degrees of each other.
At magnitude -2, Jupiter has been the brightest morning sky object. It is now rising just after midnight and will be rising about four minutes earlier every night, so we shouldn’t have to wait too long until it is an evening object.
Finally, I should mention a comet that might be visible with binoculars in early February. Besides being an observing challenge, Comet 45P/Honda-Mrkos-Pajdusakova is also a good spelling challenge. This comet has a short period of only 5.25 years and just passed perihelion, its closest approach to the sun, on Dec. 31. It will make its closest approach to Earth on Feb. 11 and might be as bright as magnitude 6 then. That would put it just at the limit of naked-eye visibility, so use an online chart, such as the one in the URL listed to get updated information and help find it.
Charles Hakes teaches in the physics and engineering department at Fort Lewis College and is the director of the Fort Lewis Observatory. Email him at hakes_c@fortlewis.edu.
Useful links
Comet 45P/Honda-Mrkos-Pajdusakova:
https://theskylive.com/45p-info
Astronomy picture of the day:
http://apod.nasa.gov/apod/
An astronomer’s forecast for Durango:
http://bit.ly/2eXWa64
Old Fort Lewis Observatory:
www.fortlewis.edu/observatory
Four Corners Stargazers:
