Super(bowl) Targets, Moon Renewed, Planet Fun in the Morning Sky, and Venus Dances with Deep Sky Partners!
Here are a few suggestions for your evening viewing this week. First, you can trace out the bright stars forming the gigantic football-shaped Winter Hexagon asterism — no binoculars needed! Start by finding the extremely bright star Sirius sitting low in the southern evening sky. From there, look for bluish Rigel sitting 2.5 fist diameters to Sirius’ upper right, then look well above Rigel for warm-tinted Aldebaran, and continue to Aldebaran’s upper left to reach yellowish Capella at the top of the asterism. Now descend on the football’s left side. The bright matched pair of stars Castor and Pollux is three fist diameters to the lower left of Capella. Finally, bright white Procyon is well below those twins — roughly between them and Sirius.
In early evening during early February, the constellation of Perseus (the Hero) is positioned nearly overhead in the northern sky. A very large open star cluster designated Melotte 20 surrounds Perseus’ brightest star Mirfak (Alpha Persei). The cluster is also known as the Alpha Persei Moving Group and the Perseus OB3 Association. It consists of about 100 young, massive, hot B- and A-class stars spanning 3 degrees (6 full moon diameters) of the sky. Melotte 20 can be seen with unaided eyes, and improves in binoculars and widefield telescopes. It is approximately 600 light years from the sun and is moving as a group. The star Mirfak, which is an elderly yellow supergiant that has evolved out of its blue phase and it is now fusing helium into carbon and oxygen in its core, is moving with them.
The constellation of Auriga (the Charioteer) occupies a position high in the eastern sky during evening. The Milky Way passes directly through Auriga, so that part of the sky is rich in open star clusters that are visible with unaided eyes from dark sky locations. And binoculars and telescopes will readily show them in moderately light-polluted skies. The bright clusters named Messier 38, Messier 36, and Messier 37 form a downward curving chain that starts a fist’s diameter to the right of the constellation’s brightest star, Capella.
The Moon and Planets
The moon will reach its new moon phase, hidden from view and close to the sun, on Monday afternoon, so we’ll benefit from nice dark skies for most of this week. Sharp-eyed observers might spot the delicate crescent of the young moon low in the west-southwestern sky for a few minutes after sunset on Tuesday. For the rest of the week, the moon will wax fuller and climb higher, lingering longer in the evening sky.
From Tuesday to Sunday, the moon will traverse the dim constellation of Aquarius (the Water-Bearer), and also skip back and forth between Pisces (the Fishes) and Cetus (the Whale) (Their shared border is crooked!) In the western evening sky on Sunday, February 10, the waxing crescent moon will pass a slim palm’s width to the lower left (south) of Mars and Uranus. Reddish Mars will be visible to the naked eye, but much more distant Uranus, which will be sitting 1.6 finger widths to Mars’ upper left, will require binoculars or a telescope.
Mars remains an obvious target this week. After dusk, the Red Planet will appear as a medium-bright, reddish pinpoint of light halfway up the southwestern sky. It will set at about 11:30 pm local time. Mars is slowly shrinking in size and brightness as we increase our distance from it.
As I just mentioned, you can use Mars to help you find blue-green Uranus nowadays. The distant ice giant planet is also situated about 1.25 finger widths above, and slightly to the left of the modestly bright star Torcular (or Omega Piscium). This week, Uranus will already be at its highest point, over the southern horizon (the best position for seeing it clearly) after dusk, then set at around 11:30 pm local time. Dim, blue Neptune is setting too soon after sunset to be worth looking for.
Mercury has joined the evening sky this week. It will become easier and easier to see after sunset on each consecutive evening. Look just above the west-southwestern horizon.
The real planet fun is in the morning sky for the next weeks. Bright Jupiter will rise in the southeastern sky first; at about 4 am local time. Even brighter Venus will join the parade about 45 minutes later, although it is rapidly dropping sunward — and away from Jupiter. Both planets will remain visible while the morning sky brightens. Dimmer, yellowish Saturn will rise at about 6 am local time, forming a nearly straight line along the ecliptic with Venus and Jupiter.
In the southeastern pre-dawn sky from February 3 to February 11, Venus’ orbit will take it through the Milky Way and close to some well-known deep sky objects, setting up nice pairings in binoculars or telescopes at low magnification. On Sunday morning, the planet will pass 2 finger widths below the open star cluster designated Messier 23. On Monday, Venus will pass 2 fingers widths above of the Trifid Nebula (Messier 20) and the Messier 21 open cluster. On Friday and Saturday morning, Venus will pass 3.5 finger widths below the bright Sagittarius Star Cloud (Messier 24). And on Sunday morning, it will land 2 finger widths to the lower right of the Messier 25 cluster.
Astronomy Skylights for the week of February 3rd, 2019 by Chris Vaughan.
Keep looking up, and enjoy the sky when you do. I love questions and requests — so, send me some!