The Sky This Week, 2017 January 17 - 24
|Messier 42, the Great Orion Nebula, imaged 2016 December 31
with a 102mm f/6.6 Explore Scientific AR-102 refractor
and a Canon EOS Rebel T2i DSLR from Mollusk, Virginia
The Moon wanes in the morning sky this week, starting the week among the springtime constellations, then moving into the first rising stars of the summer sky. Last Quarter occurs on the 19th at 5:13 pm Eastern Standard Time. Early risers have a couple of good photo opportunities in the pre-dawn hours as Luna passes just north of the planet Jupiter and the bright star Spica on the morning of the 19th. She stands close to Saturn in the southeastern sky as twilight gathers on the morning of the 24th.
The first citizen-science observing campaign for 2017’s Globe at Night program gets underway on the evening of the 19th and runs through the 28th. The goal of the program is to monitor the brightness of the night sky on a global scale to map out areas that can be considered "dark sky friendly" to amateur and professional astronomers alike. The web-based program invites anyone with an interest in the night sky to submit their observations of key constellations throughout the year. In 2016 over 14,000 people contributed observations, and this year they hope to surpass that number. This is a perfect time to get started, since the constellation that is the center of attention is Orion, perhaps the brightest and most recognized star pattern in the heavens. Located along the celestial equator, Orion is visible from every inhabited place on the planet and sports a variety of stars over a wide range of visible magnitudes. To participate in the program visit the Globe at Night website. There you’ll receive instructions and can view star maps with different magnitude cutoffs. If you have a smart phone you can download apps that will guide you through the process. You may submit as many observations as you wish, and I encourage everyone to do so, especially when vacationing away from city lights. Why should we do this? Dark skies are becoming harder to find; it is estimated that some 80% of the U.S. population has never seen the Milky Way! Artificial lighting not only robs us of a clear view of the sky, it also upsets biological cycles in many of the planet’s species, including humans. Fortunately controlling "light pollution" is easily done with today’s lighting technology, and it saves energy resources that can be applied to another purpose. Your participation is the key.
After you’ve counted stars in Orion, take a few minutes to sweep over the constellation with binoculars. This simple optical aid really enhances the colors of the Hunter’s stars and brings a host of fainter ones into view. One of my favorite areas to look at is the Hunter’s "Sword", which dangles just below the left side of the famous "Belt" stars. With the naked eye you can see three faint clumps of stars, but the binoculars reveal much more. The top and bottom "stars" turn out to be clusters of blue luminaries, while the middle member shows stars embedded in a glowing mass of light. This is the famous Great Nebula, Messier 42, the site where most of the stars in the constellation formed. Often regarded as one of the telescopic showpieces of the sky, it is one of the largest stellar nurseries in the Galaxy.
Venus dominates the western sky in the early evening. There is no mistaking the dazzling planet; under a dark sky she is bright enough to cast shadows. She is now at her best placement in the evening sky and will remain a fixture until March, when she will undergo a precipitous drop toward the Sun.
Mars remains a few steps ahead of Venus as the two planets move into the dim constellation of Pisces. The two objects are just over six degrees apart by the week’s end. For the next few weeks they will stay in his configuration before Venus falls away from the red planet.
Jupiter crosses the meridian at around 6:00 am EST, placing him in an ideal spot for a telescopic view before starting your day. Old Jove is now just over three degrees from the bright star Spica, and he’ll spend the next few weeks near the star. The Moon pays a visit on the morning of the 19th.
You’ll find Saturn low on the southeast about 45 minutes before sunrise in the gathering morning twilight. The Moon is close to the ringed planet on the morning of the 24th.