The game’s afoot! A cosmic menagerie offers sky-watchers an exciting chase this week, with everything from a mythical steed to a red bull’s eye.
Moon and Pegasus. After nightfall on Monday, February 3, folks in the Northern Hemisphere can look for the Great Square of Pegasus. Appearing tipped on one corner, the distinct four-sided pattern represents the chest of the mythological horse, Pegasus. Hanging midway up the southwest sky, the waxing crescent moon (in Pisces) will appear just to the left of the equine constellation and point toward it.
Beyond the Great Square, the rest of the constellation is a little more of a challenge to pick out, requiring either binoculars or a trip to dark skies, well away from city lights, to view all of its stars.
A large piece of celestial real estate, the Great Square spans the width of more than 30 full moons set side by side. Though each corner star is only moderately bright, they are relatively easy to locate because there are no stars near them that are as luminous.
Green Giant Companion. Another celestial attraction arrives on Monday evening. The moon will guide you to Uranus, the seventh planet from the sun. Shining at around magnitude 5, it is technically visible with the naked eye as a very faint green star, but binoculars or a small telescope will make it much easier to locate, as will viewing from a dark location. The gas giant will appear less than 2 degrees below and to the left of the moon, less than the width of your thumb held at arm’s length.
At a stately distance of 1.9 billion miles (3.1 billion kilometers) from Earth, the sunlight reflected off the green giant’s cloud-tops takes 2 hours and 52 minutes to reach us.
Double Shadows on Jupiter. In the early morning hours of Thursday, February 6, two of Jupiter’s largest moons will simultaneously cast their shadows onto the upper cloud deck of the largest planet in the solar system. Look for the two tiny, black dots to cross from 3:22 a.m. MST (2:22 a.m. PST) to 5:40 a.m. MST (4:40 a.m. PST).
The moons, Europa and Callisto, will appear to transit at the same time. While Europa is slightly smaller than Earth’s own moon and Callisto is about the size of planet Mercury, both are thought to harbor ice-encrusted oceans that may offer environments suitable for life. Sky-watchers in the western half of North America and Hawaii will be in the best position to catch this fleeting event, since Jupiter will be too low, as it sets in the western horizon, for those in the eastern time zone to view.
Moon and Seven Sisters. In the early evening of Friday, February 7, look for the stunning first-quarter moon to point the way to the Pleiades star cluster high in the southwestern sky, hanging to the upper right of the moon (lower right of the moon in the northwest for those in the Southern Hemisphere). Also known as the Seven Sisters from Greek mythology, this fuzzy patch of stars, which takes the shape of a tiny version of the Big Dipper, is easily glimpsed with the naked eye, even from light-polluted city suburbs.
However, binoculars and small telescopes will reveal a jewel-box of dozens of white diamonds huddled together in the sky. Look carefully through the eyepiece under low magnification and try to catch sight of the faint blue nebulosity that still swaddles these hot, young stars, which lie some 400 light-years from Earth.
Eye of the Bull. By the evening of Saturday, February 8, the moon will have slid farther south, resting to the left of the sparkling orange-yellow star Aldebaran, the red eye of Taurus, the bull (the moon will be lying below Aldebaran in the Southern Hemisphere). At 65 light-years away, we see this red giant star as it looked in 1949. That same year, NATO was established, the Soviets began testing atomic weapons, and George Orwell’s famous book 1984 was published.
As a fun observation challenge, try to see if you can spot Aldebaran during the day on Saturday. Because it will be only 3 degrees to the right of the moon, it should be easy to locate with binoculars. Let us know how early in the day you can spot this brilliant star!