October is jam-packed with sky-watching delights, from shooting stars created by a famed comet to a celestial dance featuring the moon, Mars, and Venus. The night skies will also showcase a far-flung planet at its best for the year, while early mornings will offer a lunar hide-and-seek with a brilliant star.
So dust off those binoculars, and mark your October calendar!
Mars and Venus Join Forces—October 5
Early risers looking toward the low eastern sky an hour before local sunrise will be greeted by the planetary duo Venus and Mars. Try using binoculars to pierce the morning glow and pick out super-bright Venus from fainter, ruddy Mars as they seem to hover over the horizon.
Moon Meets Stellar Bull's Eye—October 9
On this night, the waning gibbous moon will be rising near local midnight in the eastern sky, where it will glide through the constellation Taurus, the bull. That path will bring the moon near the bright orange star Aldebaran, which marks the eye of the mythical bull.
Moon Buzzes Beehive—October 13
For a great early morning observing challenge, look for the pairing of our moon with the Beehive star cluster in the constellation Cancer, the crab. Using binoculars or a telescope, look toward the eastern sky for the waning crescent moon starting in the predawn hours.
About seven degrees to its lower left, or the width of your fist held at arm’s length, you should find the star cluster. Known to the ancient Greeks, this mass of about a thousand stars lies 610 light-year away and stretches across 40 light-years.
From a dark site far away from city lights, the Beehive is visible to the naked eye as a small hazy patch in the sky. But with the moon so close, your best bet to spot the cluster will be to use binoculars to cut through the lunar glare.
Moon Eclipses Leo’s Heart—October 15
Lucky observers across much of North America will get to see the moon play hide-and-seek with one of the brightest stars in the overnight sky. Look for the waning crescent moon to glide up to the star Regulus, the brightest member of the constellation Leo, the lion.
The pair will be low in the eastern sky about 45 minutes before your local sunrise. Around this time, the blue-white star will appear to wink out on the lit side of the moon; it will reappear on the moon’s unlit side about an hour later. The best seats in the house will be in eastern North America, where the entire event will be visible. Those in the west will only catch the second half of the show, as the moon rises and the star pops back into view.
Zodiacal Lights—October 15-30
For about two weeks, observers in the Northern Hemisphere will have their best chance to see an ethereal display called the zodiacal lights thanks to a nearly moonless sky in the predawn hours. The phenomenon is caused by sunlight reflecting off countless dust particles that are scattered between the planets along the plane of the solar system.
In the dark countryside far from city lights, look for a pyramid-shaped glow fainter than the Milky Way rising above the eastern horizon. This month, Venus and Mars will be visible at the base of this pyramid of light.
Planetary Pair Hosts Moon—October 17
The beautiful morning pairing of Venus and Mars will get even more eye-catching as the planetary pair is joined by the thin sliver of the moon low in the eastern sky about 45 minutes before local sunrise. The glow from the early morning twilight might make viewing Mars with the naked eye a bit of a challenge, so try using binoculars to scan for the orange-red dot to the upper right of the moon.
Big, Bright Uranus—October 19
The distant ice giant Uranus reaches opposition this month, which means it will sit opposite to the sun in our sky and will be visible all night long. Opposition also marks the planet’s closest approach to Earth, which will make it brighter to our eyes than at any other time of the year.
Over the next few weeks, the distant world will be about 1.7 billion miles from Earth, which means sunlight reflected off its icy cloud tops will take nearly three hours to reach us. Even shining at its brightest, ranus is barely visible with the naked eye from a very dark location and is best seen through mounted binoculars or a backyard telescope.
Start looking in the southeast sky within the constellation Pisces, the fish. Scan the constellation carefully, and look for a tiny blue-green disk to pop out against the background of fainter stars.
Orionid Meteor Shower Peaks—October 21
Look for a flurry of shooting stars later in the month as Earth slams into the Orionid meteor cloud, the debris field shed from Halley’s comet. While the famed icy interloper won’t be back in our neck of the woods until 2061, we can see bits and pieces of it burning up in our skies every year around the end of October.
This year, the meteor shower will be peaking under moonless skies, so viewing is expected to be exceptionally good as long as clear skies prevail. Under ideal conditions, expect to count as many as 10 to 15 shooting stars an hour in the dark predawn skies. Look for the meteors to radiate from their namesake constellation, Orion, the hunter, which will be visible in the northeastern sky at that time.
Bouncing Saturn—October 23-24
After darkness falls on both of these nights, face the southern sky and look for the crescent moon to pair with bright, yellow-hued Saturn. Earth’s moon will appear to pop from the ringed planet’s right side to its left from night to night. (Explore our interactive of NASA's most recent mission to Saturn.)
Pallas Prime Time—October 29
The second largest asteroid in the solar system will reach opposition on this night, making it appear its brightest in binoculars and telescopes for 2017. At just over 155 million miles from Earth, Pallas shines at magnitude 8.3, putting it well within the reach of binoculars. Late at night, face the southeastern sky and hunt for the asteroid in the constellation Eridanus, the river, just next to the more familiar constellation Orion.