Skywatch Line for Monday and Tuesday, February 22 and 23, 2016

This is the Dudley Observatory Skywatch Line for Monday and Tuesday, February 22nd and 23rd written by Joe Slomka.

The Sun sets at 5:35 PM; night falls at 7:08. Dawn begins at 5:07 AM and ends with sunrise at 6:41.

The twilight sky contains only Uranus and the Moon. The Full Moon rises ten minutes after sunset. Native Americans of the Northeast had names for the Moons of different seasons. This Full Moon was called the “Snow Moon,” since the usually deep snow hampered hunters. Some tribes called it the “Hunger Moon,” also because it impeded hunters trying to find food for their tribe. The Moon sets at 7 AM Tuesday, and 7:30 AM on Wednesday. Monday night, the Moon hovers beneath Leo’s belly. Tuesday finds it two degrees away from Jupiter near Leo’s hind leg.

Uranus can be found at nightfall in Pisces. It appears as a sixth magnitude dot in our telescopes. It requires finder charts from astronomical magazines, websites and apps and sets by 9:45 PM.

Jupiter rises after the Full Moon. Jupiter is one of the few objects that resist the lunar glare. While binocular users can see the planet and its Galilean moons, telescopic observers can see weather bands on Jupiter and the Great Red Spot, a giant storm. The Great Red spot can be seen at 9:34 PM on Monday, and at 3:21 AM on Wednesday. They can also see the moon Ganymede cast its shadow on Jupiter at 2:56 AM Wednesday, followed by the moon itself at 4:17 AM. Jupiter is best seen at 1:11 AM and sets at 7:32 AM.

After Midnight, Mars rises at 12:23 AM. Zero magnitude Mars still inhabits Libra. It should be an obvious red dot amid the dim constellation. Saturn rises at 2:02 AM in Ophiuchus. Its cream color should distinguish it from surrounding stars, and its eight degree separation from Antares, the bright red star in Scorpius, helps find it. Venus, rises at 5:35 AM, blazes at minus 4 magnitude and occupies Capricornus. In telescopes, it appears about 90 percent illuminated. Mercury is last, rising at 5:55 AM. It is only two degrees above the horizon. A sky watcher should use brilliant Venus as a start, and look five degrees below to find the minus 0.4 magnitude planet. An unobstructed horizon assists in finding both Venus and Mercury.

After sunset, the giant constellation Orion appears. Canis Major, the Big Dog, follows at Orion’s heels. Sirius, the Dog Star and its brightest star, is the seventh closest star to our Solar System, at 8.6 light-years. Although stars seem fixed in our sky, they are actually traveling in different directions and speeds. Sirius is one of these. In sixty thousand years, it will approach to 7.8 light-years and increase its brightness marginally. Sirius is not a solitary star; it has a companion, appropriately nicknamed “The Pup.” Telescope makers, testing a new telescope, accidentally discovered “The Pup” in January 1862. This star closely orbits Sirius once every fifty years. Sirius B, as the companion is formally called, is much smaller and dimmer than the primary. The Pup is currently distancing itself from Sirius and can be seen with high powers in medium to large amateur telescopes, once Sirius’ glare is blocked.

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