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The night sky tonight and on any clear night offers an ever-changing display of fascinating objects you can see, from stars and constellations to bright planets, often the moon, and sometimes special events like meteor showers. Observing the night sky can be done with no special equipment, although a sky map can be very useful, and a good beginner telescope or binoculars will enhance some experiences and bring some otherwise invisible objects into view. You can also use astronomy accessories to make your observing easier, and use our Satellite Tracker page powered by N2YO.com to find out when to see the International Space Station and other satellites. Below, find out what's up in the night sky tonight (Planets Visible Now, Moon Phases, Observing Highlights This Month) plus other resources (Skywatching Terms, Night Sky Observing Tips and Further Reading).

The night sky is more than just the moon and stars, if you know when and where to look.
The night sky is more than just the moon and stars, if you know when and where to look.
Credit: Karl Tate/SPACE.com

Monthly skywatching information is provided to Space.com by Chris Vaughan of Starry Night Education, the leader in space science curriculum solutions. Follow Starry Night on Twitter @StarryNightEdu.

Editor's note: If you have an amazing skywatching photo you'd like to share for a possible story or image gallery, please contact managing editor Tariq Malik at spacephotos@space.com.

Yearly Night Sky Guides:

When, Where and How to See the Planets in the 2018 Night Sky

The Top Skywatching Events to Look for in 2018

The Brightest Planets in October's Night Sky: How to See them (and When)

Best Night Sky Events of October 2018 (Stargazing Maps) 

Tuesday, October 2 at 5:45 a.m. EDT — Last Quarter Moon

At its last quarter phase, the moon rises around midnight and remains visible in the southern sky all morning. At this phase, the moon is illuminated on its western side, towards the pre-dawn sun. Last quarter moons are positioned ahead of the Earth in our trip around the sun. About 3½ hours later, Earth will occupy that same location in space. After this phase, the waning moon traverses the last quarter of its orbit around the earth, on the way to new moon. 

Thursday, October 4 pre-dawn — Moon Buzzes the Beehive

When the waning crescent moon rises in the early hours of Thursday, October 4, it will be located less than 2 degrees to the right of the large open star cluster known as the Beehive and Messier 11 in Cancer. Minimum separation will occur at 5 a.m. EDT. At that time, the moon will be 1 degree to the cluster's lower right, and both objects will fit within the field of view of a telescope at low magnification (orange circle). 

Monday, October 8 — Draconids Meteor Shower Peaks

The annual Draconids Meteor Shower will peak overnight on the night of Monday, October 8. This shower, generated by debris dropped by Comet 21P/Giacobini-Zinner, usually delivers relatively few meteors. But it has occasionally been much more prolific. The best time to watch for Draconids will be after dusk, when the radiant in Draco is high in the northern sky.

Monday, October 8 pre-dawn — Morning Zodiacal Light for Mid-Northern Observers

During moonless periods in October and October annually, the steep morning ecliptic favors the appearance of the zodiacal light in the eastern sky for about half an hour before dawn. This is reflected sunlight from interplanetary particles concentrated in the plane of the solar system. During the two weeks starting just before the new moon on October 8, look east below the stars of Cancer for a broad wedge of faint light rising from the horizon and centered on the ecliptic (marked by green line). Don't confuse it with the Milky Way, which is sitting further to the southeast. 

Tuesday, October 8 at 11:47 p.m. EDT — New Moon

At its new phase, the moon is travelling between Earth and the sun. Since sunlight can only reach the far side of the moon, and the moon is in the same region of the sky as the sun, the moon will be completely hidden from view. 

Thursday, October 11 evening — Young Moon meets Jupiter

Low in the southwestern sky for a short period after sunset on Thursday, October 11, the young crescent moon will sit 3 degrees to the lower right of the very bright planet Jupiter. The pair of objects will be visible together in the field of view of binoculars (orange circle) until they set shortly after 8 p.m. local time. 

Sunday, October 14 evening — Moon Passes Saturn

After dusk in the southwestern evening sky on Sunday, October 14, the waxing crescent moon will sit less than 2 degrees to the right of Saturn. The pair of objects will be visible together in the field of view of binoculars (orange circle) and will set at about 10:30 p.m. local time. Over the course of the evening, the moon's eastward orbital motion (green line) will carry it past Saturn. Their closest approach of 0.75 degrees, which occurs at 04:00 GMT, will be visible to observers in western North America.

Tuesday, October 16 overnight — Juno Reverses Direction

On Tuesday, October 15, the main belt asteroid designated (3) Juno will cease its regular eastward orbital motion (red path) through the stars and commence a westward retrograde loop that will last until late December. Look for the magnitude 7.9 object in the eastern evening sky among the stars of southern Taurus.
On Tuesday, October 15, the main belt asteroid designated (3) Juno will cease its regular eastward orbital motion (red path) through the stars and commence a westward retrograde loop that will last until late December. Look for the magnitude 7.9 object in the eastern evening sky among the stars of southern Taurus.
Credit: Starry Night software

On Tuesday, October 15, the main belt asteroid designated (3) Juno will cease its regular eastward orbital motion (red path) through the stars and commence a westward retrograde loop that will last until late December. Look for the magnitude 7.9 object in the eastern evening sky among the stars of southern Taurus. 

Tuesday, October 16 at 2:02 p.m. EDT — First Quarter Moon

After the moon has completed the first quarter of its orbit around Earth, the relative positions of the Earth, sun, and moon cause us to see it half-illuminated - on its eastern side. A first quarter moon always rises around noon and sets around midnight local time, so it is also visible in the afternoon daytime sky. The evenings around first quarter are the best times to see the lunar terrain when it is dramatically lit by low-angled sunlight. 

Wednesday, October 17 evening — Moon Hops over Mars

In the southern sky on the evening of Wednesday, October 17, the first quarter moon will be positioned about 6 degrees to the right of Mars. From dusk until they set at around 1 a.m. local time, the moon's eastward orbital motion (green line) will carry it towards the Red Planet. The following evening, the moon will appear a similar distance from Mars, but now on the left side of the planet. 

Sunday, October 21 pre-dawn — Orionids Meteor Shower Peak

The annual Orionid meteor shower, composed of debris from repeated passages of Comet Halley, runs from September 23 to November 27. It peaks between midnight and dawn on Saturday, October 21 under a dark moonless sky. At that time the sky overhead is moving directly into the densest region of the particle field, producing 10-20 fast meteors per hour. The meteors can appear anywhere in the sky, but will be travelling away from the constellation of Orion. 

Tuesday, October 23 all night — Uranus at Opposition

 

Uranus will reach opposition on October 23, when it will be brightest (magnitude 5.7) and closest to Earth for the year and visible all night. But due to the presence of the nearly full moon, observers will have better luck seeing Uranus several nights ahead or after opposition night. During autumn this year, the blue-green planet will be moving retrograde westwards towards the two fishes of Pisces.

Tuesday, October 23 at 8:19 p.m. — Algol at Minimum Brightness

 

The "Demon Star" Algol in Perseus is among the most accessible variable stars for beginner skywatchers. Its naked-eye brightness dims noticeably for about 10 hours once every 2 days, 20 hours, and 49 minutes because a dim companion star orbiting nearly edge-on to Earth crosses in front of the much brighter main star. On Tuesday, October 23 at 8:19 p.m. EDT, Algol will reach its minimum brightness of magnitude 3.4. At that time, it will sit partway up the northeastern horizon. By 1:19 a.m. EDT, it will be approaching the zenith and will have brightened to its usual magnitude of 2.1. 

Wednesday, October 24 at 12:45 p.m. EDT — Full Hunter's Moon

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 and Pisces. Since it's opposite the sun on this day of the lunar month, it rises at sunset and sets at sunrise.

Friday, October 26 over night — Moon Crosses the Bull

 

Overnight on Friday, October 26, the waning gibbous moon will approach and then pass through the Hyades star cluster, the stars that form the triangular face of Taurus the bull. The moon will enter the cluster at approximately 3 a.m. EDT. By sunset in the Eastern time zone, the moon will be central. Observers farther west will be able to see the moon pass only 0.75 degrees above Aldebaran, Taurus' brightest star at about 8 a.m. Pacific time. This is also an opportunity to look for Aldebaran in daylight using the nearby moon as a guide.

Sunday, October 28 after sunset — Mercury and Jupiter Meet

Very low in the southwestern sky after sunset on Sunday, October 28, bright Jupiter will sit 3 degrees above much dimmer Mercury. The pair of planets will be visible together for several evenings surrounding that date. Mercury will set first at about 7 p.m. local time. 

Wednesday, October 31 midnight to dawn — Moon Approaches the Beehive

For the second time this month, the moon will pass close to the Beehive Star cluster in Cancer. This time, the orbital motion of the last quarter moon (green line) will slowly carry it towards the cluster – starting 6 degrees to the upper right of the cluster when it rises after midnight, and closing to within half that distance as the dawn twilight begins. 

Wednesday, October 31 at 12:40 p.m. EDT — Last Quarter Moon Again

Because lunar phases repeat every 29.5 days, from time to time a phase that occurs in the opening days of a calendar month can repeat at the month end. At its last quarter phase, the moon rises around midnight and remains visible in the southern sky all morning. At this phase, the moon is illuminated on its western side, towards the pre-dawn sun.

 

Following its conjunction with the sun in late September, Mercury will spend October in the western evening sky in an apparition that will be a poor one for mid-northern latitude observers, but very good for Southern Hemisphere observers. Viewed through a telescope during October, Mercury's disk will exhibit a phase that will continuously wane from nearly fully illuminated to 72% full. During the month, the planet's apparent disk diameter will slowly increase. 

Venus' long evening apparition of 2018 will end as October begins. The very bright inner planet (visual magnitude -4.75) will only be visible during the first week of October, when it will set in the southwestern sky only half an hour after the sun. In a telescope,, it will exhibit a waning crescent that grows in apparent size as the planet moves towards Earth. For the rest of October, Venus will be too close to the sun for observing, passing below the sun in inferior conjunction on October 26. At month's end, Venus will enter the eastern pre-dawn sky. 

Mars, well positioned for viewing all month, will spend October moving eastward through the stars of central Capricornus. It will be relatively low in the southern evening sky and set after 1 a.m. local time. During the month, as Earth pulls away from the Red Planet, Mars will remain a bright reddish naked-eye object, but its visual brightness will diminish from magnitude -1.3 to -1.5. Meanwhile, the planet's apparent disk diameter will decrease from 15.6 arc-seconds to 11.9 arc-seconds. On the evenings of Wednesday, October 17 and Thursday, October 18, the waxing gibbous moon will land 5.5 degrees to the right and left of Mars, respectively. 

The available time for observing Jupiter will shorten considerably during October. The very bright planet (visual magnitude -1.8) will be positioned low in the southwestern evening sky all month. It will be moving eastward through the stars of central Libra, pulling away from the nearby bright double star Zubenelgenubi. Jupiter will set at about 8:45 p.m. local time on October 1 and at 7 p.m., in twilight, at month's end. On Thursday, October 11, the young crescent moon will sit 3 degrees to the lower right of Jupiter. The pair of objects will be visible together in the field of view of binoculars. 

Saturn will be visible during October as a medium-bright (visual magnitude 0.5), yellowish object in the lower part of the southern evening sky. It will be moving slowly eastward within the Milky Way, to the upper right of the stars that form Sagittarius' teapot-shaped asterism. All month long, the planet will be positioned only a few degrees to the upper left of two fine deep sky objects – The Trifid Nebula and the Lagoon Nebula. Saturn's rings, which subtend an angular size of about 37 arc-seconds, continue to be well open because the planet's northern pole is tilted roughly sunward. On the evening of Sunday, October 14, the waxing crescent moon will sit less than 2 degrees to the right of Saturn. 

Blue-green Uranus (magnitude 5.7) will spend October moving slowly retrograde westward among the stars of western Aries. On October 1, it will sit less than 3.5 degrees to the left of the naked-eye star Omicron (o) Piscium, closing to within 2.5 degrees left of that star at month end. Uranus will be observable all night after rising in the eastern sky after 9 p.m. local time. The planet will reach opposition, its closest approach to Earth and its brightest and largest appearance on October 23. 

As October opens, blue-tinted Neptune will be recently past opposition, leaving it visible all night, and nearly at its largest and brightest (magnitude 7.8) for 2018. It will spend October moving retrograde westward through the stars of eastern Aquarius - shifting slowly toward that constellation's naked-eye star, Hydor (Lambda (λ) Aquarii). In early October, the planet will sit approximately midway between Hydor and the slightly fainter star Phi (φ) Aquarii. At month end, it will be 2 degrees to the left of Hydor. 

Gibbous: Used to describe a planet or moon that is more than 50 percent illuminated.

Asterism: A noteworthy or striking pattern of stars within a larger constellation.

Degrees (measuring the sky): The sky is 360 degrees all the way around, which means roughly 180 degrees from horizon to horizon. It's easy to measure distances between objects: Your fist on an outstretched arm covers about 10 degrees of sky, while a finger covers about one degree.

Visual Magnitude: This is the astronomer's scale for measuring the brightness of objects in the sky. The dimmest object visible in the night sky under perfectly dark conditions is about magnitude 6.5. Brighter stars are magnitude 2 or 1. The brightest objects get negative numbers. Venus can be as bright as magnitude minus 4.9. The full moon is minus 12.7 and the sun is minus 26.8.

Terminator: The boundary on the moon between sunlight and shadow.

Zenith: The point in the sky directly overhead.

  • Adjust to the dark: If you wish to observe faint objects, such as meteors or dim stars, give your eyes at least 15 minutes to adjust to the darkness.
  • Light Pollution: Even from a big city, one can see the moon, a handful of bright stars and sometimes the brightest planets. But to fully enjoy the heavens — especially a meteor shower, the constellations, or to see the amazing swath across the sky that represents our view toward the center of the Milky Way Galaxy — rural areas are best for night sky viewing. If you're stuck in a city or suburban area, a building can be used to block ambient light (or moonlight) to help reveal fainter objects. If you're in the suburbs, simply turning off outdoor lights can help.
  • Prepare for skywatching: If you plan to be out for more than a few minutes, and it's not a warm summer evening, dress warmer than you think necessary. An hour of observing a winter meteor shower can chill you to the bone. A blanket or lounge chair will prove much more comfortable than standing or sitting in a chair and craning your neck to see overhead.
  • Daytime skywatching: When Venus is visible (that is, not in front of or behind the sun) it can often be spotted during the day. But you'll need to know where to look. A sky map is helpful. When the sun has large sunspots, they can be seen without a telescope. However, it's unsafe to look at the sun without protective eyewear. See our video on how to safely observe the sun, or our safe sunwatching infographic.

Moon Phases: How the lunar cycle works, from full moon to new moon. Also find out when is the next full moon.

Constellations: The history of the Zodiac constellations and their place in night sky observing.

Lunar Eclipses: How they work, plus find out when's the next lunar eclipse.

Solar Eclipses: How they work, the types, and when the next one occurs.