Astronomers have announced two new moons discovered orbiting Jupiter bringing its total to 69, something to wonder about as you see it you sky this week. Meanwhile, Saturn reaches opposition on Thursday making it visible from sunset to sunrise. Here is your guide to the sky for June 12 to 1188, 2017…
Constellations – Aquila rising
Last of the constellations rounding out the Summer Triangle is Aquila the Eagle. This diamond shaped group of stars is marked by Altair the 12th brightest star in the sky which is only 16.8 light years from Earth making it one of our nearer stellar neighbors. In 2007 astronomers determined this star spins on its axis once every 10 hours compared to 24 hours for the Earth. This rapid rotation flattens the star a bit, making it an oblate spheroid, or a star with a middle-aged bulge. The star is also a variable one, but it requires advanced instruments to detect this. In Greek mythology Aquila was an eagle favored by Zeus who played a role in the abduction of Ganymede whom he carried off to Mount Olympus on Zeus’ command to become the cupbearer to the gods. In India, Altair with its two flanking stars, Tarazed and Alshain are thought to footprints of the god Vishnu in the stars. Do check out this rising eagle in your eastern sky after sunset.
Planets in the Sky – Two new moons for Jupiter, Saturn at Opposition
Monday morning try catching Mercury early just before sunrise. To find it look for the planet 5 degrees north of the bright red star Aldebaran in Taurus. Thursday evening Saturn reaches opposition meaning is 180 degrees from the Sun. It will rise at sunset and set at sunrise on that evening. Mars is lost in the glow of sunset, while Venus rises around 2:40 am and is bright in the sky before dawn. Jupiter is in the southwestern sky after sunset, and the brightest star like object visible in the evening sky. This week astronomers announced the discovery two new small moons bringing the giants total to 69. While these new moons are too small to be seen in backyard telescopes, it is amazing that we continue to find new ones around this gas giant. Both of these moons have retrograde orbits, with inclinations greater than 90 degrees, meaning that they move opposite that of the planet’s spin. These orbits imply that they formed elsewhere in the outer solar system and were captured by Jupiter.
Sun – Earth – Moon
Sunrise this week is 4:49 am and sunset at 8:23 pm, yet civil twilight begins at 4:11am. Last Quarter moon takes place on Saturday at 7:33 am.
Satellites to See – Tiangong 1 this week
Look for the Tiangong 1 on Monday morning from 3:51 am 3:57 am moving from west-southwest to east. See it again on Tuesday from 4:11 am to 4:17 am moving from west to east-southeast. On Thursday night it makes its brightest pass for the week from 3:17 am to 3:22 am moving from southwest to southeast. See it on Friday from 3:36 am to 3:41 am moving from west to southeast.
Look for the rising eagle of Aquila, check out Saturn and Jupiter and enjoy the warm weather outside under star lit skies. Happy stargazing and keep your eye on the sky!