Happy October! It’s getting dark noticeably earlier nowadays, and winter favorites Taurus, Gemini, and Orion are rising in late evening. An annual meteor shower called the Orionids starts this week, so keep an eye out anywhere in the sky for “shooting stars” that are moving in a direction away from Orion.
The Moon and Planets
The moon reaches its full phase, directly opposite the sun in the sky at 2:40 pm on Thursday, so it will already have a dark sliver on its right side when it rises about four hours later. The full moon of October, traditionally called the Hunter’s Moon, Blood Moon, or Sanguine Moon, always shines in or near the stars of Cetus (the Whale) and Pisces (the Fishes). This month’s full moon is also the Harvest Moon, traditionally defined as the full moon closest to the September equinox.
By next Sunday evening, the waning gibbous moon will reach the stars making the triangular face of Taurus (the Bull). Through Sunday night and into Monday morning, the moon will pass among them. Observers in central and northeastern Asia will get to see the moon pass in front of (or occult) the bright star Aldebaran, which represents one of the bull’s eyes, at about 19:00 UT.
If you are out under a clear early evening sky this week, look for Jupiter very low in the west, a short distance south of where the Sun went down. The giant planet sets less than hour after the sun, at about 7:30 pm local time. Our views of Jupiter will be heavily distorted because we have to look through such a deep blanket of air when it is sitting so low.
Saturn is the obvious yellowish object partway up the southern sky as the evening darkens. It sets in the west just about 10:20 pm local time. Once it’s dark, pull out your telescope and look for some of Saturn’s moons sprinkled around the ringed planet. Up to six or seven can be seen in amateur telescopes. The reflected sunlight from Saturn is taking about 85 minutes to reach us!
Blue-green Uranus is situated about halfway along the eastern (left-hand) string of stars that form Pisces (the Fishes). It’s low in the east at dusk and is observable for the rest of the night in binoculars under a dark sky. We’re approaching the days when the planet is closest and brightest for this year. To help guide you, there’s a medium-bright star about a finger’s width below Uranus. Tiny blue Neptune is also observable all night long, located in the southeastern evening sky about two finger widths to the lower left of the medium-bright star Hydor in Aquarius (the Water-Bearer). But it is too faint to be seen with unaided eyes.
Extremely bright Venus rises in the eastern sky after 5 am local time. This week, the planet continues to descend slowly sunward below Leo (the Lion). In the eastern pre-dawn sky of Thursday, October 5, Venus will sit very close indeed to much dimmer Mars. At only 0.25 degrees separation, the two planets will fit within the view of a backyard telescope’s eyepiece. The two planets will be slightly farther apart on the surrounding mornings. Speaking of Mars, it rises in the east about 5:15 am, a short while after Venus.
Keep looking up to enjoy the sky! Stargazing News for this week (from October 1st, 2017) by Chris Vaughan.