Mercury will reach its greatest eastern elongation on Oct. 29, marking one of the best evenings to see the planet this fall as it appears farthest from the sun's glare in the twilight sky.

As the solar system's innermost planet, Mercury travels an extremely tight orbit around our parent star, with an average separation of under 36 million miles (58 million kilometers). As a result, it never appears far from the sun in Earth's sky and is only ever visible near the horizon in the hours following sunset or preceding dawn, depending on the time of year.

Mercury will reach its most distant point from the sun in its current evening appearance at 4:28 p.m. EDT (2028 GMT) on Oct. 29, when it will be separated by roughly 24 degrees from our parent star, according to the practical astronomy website in-the-sky.org. Remember, the width of your clenched fist held at arms length accounts for 10 degrees of sky.

That evening, the rocky world will appear as a bright "evening star" above the southwestern horizon at sunset for viewers in the U.S, with the stars of the constellation Scorpius to its left and Libra on its right, though they will initially be lost in the glow of the setting sun.

Mercury will have an altitude of just 7 degrees at sunset on Oct. 29, so it's best to find a viewing location with a clear line of sight to the southwestern horizon to ensure that you get a good glimpse at fleet-footed World. The planet will remain visible for less than an hour after sunset, so timing is key. Atmospheric turbulence brought about by Mercury's low position on the horizon may cause it to shimmer like a star as its light makes a prolonged journey through Earth's dense atmosphere.

Observing the planet through a telescope with an aperture of 4 inches or more under dark sky conditions will reveal the moon-like phases of the distant world, though utmost care must be taken to ensure that the sun is safely below the horizon before pointing telescopic equipment in its direction. Mercury currently has the appearance of a waxing gibbous moon, with its right side lit by direct sunlight and its left bathed in shadow.

Stargazers hoping to get a closer look at Mercury should check out our roundups of the best telescopes and binoculars for observing the planets. Those new to exploring the night sky should also read our guide to the top smartphone astronomy apps, which can help pinpoint the locations of stars, galaxies and a treasure trove of other deep sky and solar system objects using augmented reality technology.

Look to the southwestern horizon at sunset on Oct. 23 to see the slender form of the crescent moon shine close to Mercury and Mars in the evening sky.

The 6%-lit waxing crescent moon will be visible roughly 5 degrees above the horizon as the sun sets on Oct. 23, with Mercury appearing as an "evening star" to the upper right of its sickle-like form and the red light of Mars shining just beyond, to form a cosmic lineup in the evening sky.

All three worlds will lie within 10 degrees of each other — roughly the width of your clenched fist held at arm's length against the night sky — with Mercury and Mars close enough to comfortably share the field of view of a pair of 10x50 binoculars. But remember - even just glancing at the sun with a pair of binoculars can lead to permanent loss of vision. Be sure to use a trusted website like TimeandDate to check sunset times for your locale and ensure that our parent star is well below the horizon before attempting to view the moon beside these planets with a magnifying aid.

The razor-thin form of the crescent moon will make for a challenging target to spot against the glow of the setting sun on Oct. 23, just two days out from its new moon phase on Oct. 21. The moon, Mercury and Mars will set less than an hour after the sun, so be sure to stake out a vantage point with a clear view of the southwestern horizon to ensure a good view of the solar system parade.

Mercury's tight orbit around the sun will see it depart Mars to travel leftward in the direction of the constellation Scorpius in the days ahead, as the crescent moon grows thicker ahead of its first quarter phase on Oct. 29, when its entire right side will be lit by direct sunlight.

Stargazers interested in getting a closer look at the wonders of the night sky should check out our roundups of the best telescopes and binoculars available in 2025, while those new to the hobby should read our roundup of the best smartphone astronomy apps for navigating the post sunset realm.

Editor's Note: If you would like to share your astrophotography with Space.com's readers, then please send your photo(s), comments, and your name and location to spacephotos@space.com.

Autumn has draped itself across the northern hemisphere, heralding the onset of longer, darker nights that serve as the perfect backdrop for amateur astronomers looking to explore the wonders of the night sky.

Our sky is constantly changing as the relentless passing of the seasons and movement of the planets, moon, comets and Earth itself bring an ever-shifting array of astronomical targets into view.

Join us as we explore a selection of spectacular sights picked to highlight the diversity of the autumn sky, which will be visible both through telescopes and binoculars, or even the naked eye, assuming one particular comet continues its brightening trend!

8 skywatching targets to look out for this autumn

Orion, the hunter

The constellation Orion rises in the east around midnight in mid-October and makes for a spectacular sight in the predawn sky, by which time the stellar formation will have drifted to a position high above the southern horizon.

Orion's Belt

Look for the three stars that make up the distinctive formation of Orion's Belt — Alnitak, Alnilam and Mintaka — shining roughly 40 degrees above the southern horizon before sunrise. To estimate 10 degrees in the sky, use the width of your clenched first held at arm's length.

Betelgeuse

Above Orion's Belt, the red giant Betelgeuse marks the hunter's right shoulder in constellation drawings, though it appears on the left when viewed in the sky. Betelgeuse, formally known as Alpha Orionis, will one day end its life in a spectacular supernova explosion upon exhausting the last of its fuel, which could be as bright as the full moon.

Orion Nebula

Those viewing from a dark sky location may also notice a blurry patch of light hanging about 5 degrees below Orion's belt. That smudge is the Orion Nebula, which at a distance of just 1,500 light-years is one of the closest star-forming regions to Earth and makes for a beautiful target through binoculars or a 6-inch telescope.

The Orionid meteor shower

The Orionid meteor shower is active from Oct. 2 to Nov. 7 and reaches a peak of activity on Oct. 20-21, when up to 20 shooting stars may be seen streaking through the night sky each hour.

Orionid meteors appear to emanate from a point in the sky known as a radiant located close to the red giant Betelgeuse. To find meteors with the longest trails, it's best to allow up to 30 minutes for your eyes to adjust to the dark and find a point 40 degrees above the radiant, where the meteor trails will be at their longest.

The shower is best viewed in the hours between midnight and dawn on Oct. 21 and unfolds against a stunningly dark, moonless sky.

The Andromeda Galaxy

The Andromeda Galaxy lies almost directly overhead in the hours surrounding midnight on October nights, presenting a perfect opportunity to observe the Milky Way's closest neighbor without the atmospheric interference that comes from being close to the horizon.

Andromeda is a vast spiral galaxy formed from the merging of multiple smaller galaxies billions of years ago. The vast cosmic structure spans about 260,000 light-years and contains over a trillion stars.

The galaxy is bright enough to be spotted by the naked eye in dark sky conditions as a faint oval-shaped blur in the night sky, while a telescope with an aperture of around 6-inches will help reveal its bright core surrounded by a haze of light.

To find Andromeda, locate the constellation Cassiopeia, which forms a prominent 'M' shape high in the northern sky. The left three stars of the 5 star formation will form a pointer, with Alpha Cassiopeiae, or Shedar as its tip, guiding you to our galactic neighbor.

Comet C/2025 A6 (Lemmon)

Now to the wildcard on our list. Comet C/2025 A6 (Lemmon), discovered on Jan. 3 by astronomers using a 60-inch telescope located in the Mt. Lemmon Observatory in Arizona. The wandering comet has brightened significantly as it has drawn closer to the sun throughout the year, prompting an increase in activity as masses of dust and gas are shed by the wandering body and subsequently illuminated by sunlight.

Comet Lemmon's bright nucleus and ethereal tail are already visible as a hazy patch of light through backyard telescopes and astronomy binoculars, while many are excited by it brightening enough to become a naked eye target in the coming weeks!

Lemmon is constantly shifting against the background stars beyond and is best viewed in the hours preceding dawn for those in the northern hemisphere. It can be found in mid-October, passing close to the bright star Psi Ursae Majoris in the constellation Ursa Major, moving towards the brightest stellar body in the constellation Canes Venatici, known as Cor Caroli.

Check out our guide on how to view and photograph comets if you're interested in capturing your own image of Comet C/2025 A6 Lemmon before it disappears from Earth's sky for over a thousand years.

The gas giant Saturn

Saturn makes for a particularly bright and magnificent target in the Autumn months, having recently reached opposition — the point at which it is opposite the sun in our sky — just a few weeks ago.

The gas giant will appear as a bright "evening star" shining above the eastern horizon at sunset in October, below the head of the great Western Fish represented in the constellation

A telescope with an aperture of 6 inches or more will allow you to resolve the cloud bands dividing its majestic disk, along with the razor-thin profile of its sweeping rings, which are currently oriented almost edge-on to Earth, following its ring plane crossing in March earlier this year. It may be beneficial to fit color filters to your telescope to help reveal subtle details in Saturn's cloud surface, according to telescope maker Celestron.

If you're looking to upgrade your equipment, check out our guides to the best telescopes and binoculars for viewing the night sky as we move towards peak astronomy season. Our guides on the best cameras and lenses for imaging the night sky can help to ensure that you're ready to make the most of the next big skywatching event.

Editor's Note: If you would like to share your astrophotography with Space.com's readers, then please send your photo(s), comments, and your name and location to spacephotos@space.com.

If you're up late on Monday night (Oct. 13), or awake in the predawn hours of Tuesday (Oct. 14), look east for a striking sight.

The moon, just hours past its last quarter phase, will rise above the east-northeastern horizon shortly before midnight local time. Shining about 6 degrees to its right will be Jupiter, the largest planet in our solar system.

To estimate the distance between them, hold out your clenched fist; it measures roughly 10 degrees across at arm's length, so the moon and Jupiter will be separated by roughly a little more than half of a fist. It is, of course, an illusion of perspective: the moon is only 235,000 miles (378,000 kilometers) from Earth. Meanwhile, Jupiter is 477 million miles (768 million km) away, more than 2,000 times farther out in space compared to our natural satellite.

Best views early Tuesday morning

Next to dazzling Venus, Jupiter is the best observer's planet during fall and much of the upcoming winter season. Currently, however, Venus is a morning object, not appearing until the break of dawn and appearing only as a brilliant dot in telescopes, leaving Jupiter unchallenged during the late evening and predawn morning hours. Look for it currently glimmering balefully just above the east-northeast horizon by 11:40 p.m. local daylight time. But Jupiter will not reach an altitude of 30 degrees above the horizon — one third of the way up in the sky — until 2:30 a.m. For some, that's considered to be the dividing line between objects that are "low" versus objects that are considered to be "well placed." Sharp telescopic views are seldom possible until an object reaches an altitude of 30 degrees, given the typical turbulent state of Earth's atmosphere.

Jupiter soaring high in Gemini

Right now, Jupiter is in the constellation of Gemini, the Twins, near the star that marks the right hand of the twin brother Pollux (Kappa Geminorum). Gemini is also where the ecliptic, the pathway of the sun, moon and planets, comes farthest north. This gives northern observers a decided advantage, for the farther north a planet is, the more time it spends above the horizon and the higher up over the southern part of the sky it will appear.

When Jupiter reaches its highest point in the southern sky, at around the time of local sunrise, it will stand about 65 degrees high for Portland, Oregon and Minneapolis/St. Paul; 70 degrees for Salt Lake City and Philadelphia; 80 degrees for Houston and New Orleans and 85 degrees (practically overhead) for Brownsville, Texas and the Florida Keys.

What to see through a telescope

In a telescope, Jupiter is always a fascinating sight. Light and dark cloud belts in the giant planet's atmosphere appear to parallel the equator and slowly change. Meanwhile, the famous Great Red Spot, appears to be contracting in size as well as wobbling like a bowl of jelly while undergoing dynamic fluctuations and changing shape, squeezing in and out. Once large enough to fit two to three Earths, the spot now fits only about one Earth.

The other attractions are the four Galilean satellites. During the overnight hours of late Monday night into Tuesday morning, steadily-held binoculars or a telescope will readily show all four of these big moons. Late Monday night into Tuesday morning, you'll see Callisto, Europa, and Io lined up on one side of the planet, with Ganymede alone on the other.

A rare 2026 occultation awaits

In a little less than a year from now, Jupiter and the moon will be part of one of the best celestial highlights of 2026. On the morning of Oct. 6, much of North America will be treated to a spectacular eclipse (occultation) of Jupiter by a waning crescent Moon just 4 days before new.

This event will be visible across much of eastern and central North America. Nocturnal (nighttime) occultations of Jupiter are quite rare for any one given place. For most U.S. locations, for instance, the last opportunity was in December 2004. The sheer beauty of a crescent moon hiding such a brilliant object as Jupiter — along with the bonus of the Galilean Satellites in binoculars and telescopes — will likely place this event near the top of "must-see" events in 2026.

Mark your calendars!

If you're looking for a telescope to view Jupiter our best telescopes for deep space guide may help. We also have a guide to astrophotography for beginners which covers everything from equipment to shooting modes and more.

Joe Rao serves as an instructor and guest lecturer at New York's Hayden Planetarium. He writes about astronomy for Natural History magazine, Sky and Telescope and other publications.

Editor's Note: If you snap a photo of Jupiter and the moon and would like to share it with Space.com's readers, send your photo(s), comments, and your name and location to spacephotos@space.com.

The past month has seen Comet C/2025 A6 (Lemmon) brightening rapidly ahead of its close approach to the sun, leading to growing excitement that it could shine brightly enough to be seen by the naked eye in mid-late October.

Solar system comets tend to become increasingly active and bright in the weeks and months leading up to perihelion — their closest approach to the sun in a given orbit — and Comet Lemmon is no exception. Heat and energy from the sun vaporizes the comet's icy deposits, transforming them into a gaseous central coma and tail that drags dusty particles along with it, which reflect sunlight and create the dramatic spectacles we see through telescopes or in the night sky.

Read on to discover where and when to look for Comet Lemmon before, during and after its flyby of Earth on Oct. 21.

Comet Lemmon has brightened from magnitude +21.5 upon its discovery in January to approximately +5.7, according to the Comet Observation Database (COBS) maintained by the Crni Vrh Observatory in Slovenia. That technically places it above the +6 detection limit of the human eye in perfect dark sky conditions, though the light cast by the waning gibbous moon will add an extra barrier to visibility in the week ahead.

If Comet Lemmon continues its current brightening trend, it could become a beautiful, hazy naked eye target in the coming weeks, with its light becoming easier to define through a pair of binoculars, or a backyard telescope.

Much like the planets and the moon, Comet Lemmon is constantly shifting relative to the stars beyond. Mid-October will see the wandering body pass close to the star Alkaphrah, or Chi Ursae Majoris in the constellation Ursa Major, just below the 'dipper' portion of the Big Dipper asterism, before beating a path through the night sky towards the star Cor Caroli in the constellation Canes Venatici.

Comet Lemmon will be in the heart of the constellation Boötes, the Herdsman, as it makes its closest approach to Earth on Oct. 21, before travelling on to pass beneath the head of the great serpent represented in the constellation Serpens on Oct. 26 to 27.

The optimal hour to search for the comet will shift depending on the time of the month in which you are looking. Comet Lemmon will be positioned high above the northeastern horizon in the hours preceding dawn in early October, but will have transitioned to the evening sky by the time it makes its close approach to Earth on Oct. 21, when it will appear low on the northwestern horizon.

Interested in capturing Comet Lemmon with a camera for yourself? Then be sure to read our guide on how to image a comet, along with our picks of the best cameras and lenses available for astrophotography in 2025. Amateur astronomers should also check out our roundups of the best telescopes and binoculars for viewing the night sky.

Editor's Note: If you would like to share your astrophotography with Space.com's readers, then please send your photo(s), comments, and your name and location to spacephotos@space.com.

If you’re delighted by the ever-changing sky, here are some of its brightest inhabitants to watch for this week just before dawn.

Just before dawn, you'll be able to view four bright planets. And now that October is here, and the days are getting shorter for those of us in the northern hemisphere, the sun rises around 7 a.m., so you don't have to get up particularly early to check out the predawn view.

Venus, as usual, is the brightest of the bunch, with Jupiter close behind. Mars and Mercury are more challenging, and you may need binoculars to spot them. Watch them over the next few weeks, and you'll see a changing pattern of bright objects. [10 Must-See Stargazing Events to Look Up for in 2015]

Venus and Mercury are tethered close to the sun, but the other planets and stars will be marching westward night by night.

This week, the waning crescent moon will be moving through the four planets toward the horizon, heading to new moon on Oct. 12.

The Moon

Thursday morning, Oct. 8, the moon will be close to Venus. In fact, the moon will even pass in front of Venus for observers in Australia, New Zealand and Melanesia.

Friday morning, Oct. 9, the moon will be in a close grouping with Mars and Jupiter.

Saturday morning, Oct. 10, the moon will be about halfway between Jupiter and Mercury, and will be a useful guide for spotting Mercury.

Finally, on Sunday morning, Oct. 11, for those of you with low eastern horizons, a thumbnail of a moon will be very close to Mercury, even passing in front of it in southern South America. Look for Mercury just above and to the left of the moon.

Parallax effect

A good way to see the effects of parallax, an object's movement against a more distant background, is during a close passage of the moon in front of four planets. Depending on where you live on Earth, north or south, you will see the moon as nearer or farther away from individual planets. At present, Venus is the only planet south of the ecliptic — the sun's path through the stars — so it is the most likely planet to get covered by the moon, which is also south of the ecliptic.

Another thing to look for this week is the earthshine or earthlight, from sunlight reflected onto the moon's "dark" side by the Earth. A close look will show a faintly glowing "full moon" just above the sunlit crescent.

Early gems

If you get up a little earlier this week, you will get a fine preview of the winter sky. Look for the constellation of Orion close to the meridian, and the bright star Capella directly overhead. No fewer than eight first-magnitude stars are visible in the nighttime sky. This is a wonderful chance to observe the gems of the winter sky when the temperature is a lot warmer than it will be in January, when these same objects will appear in the evening sky.

Editor's note: If you capture an amazing image of the night sky that you would like to share with Space.com and its news partners for a story or photo gallery, send photos and comments in to: spacephotos@space.com.

This article was provided to Space.com by Simulation Curriculum, the leader in space science curriculum solutions and the makers of Starry Night and SkySafari. Follow Starry Night on Twitter @StarryNightEdu. Follow us @Spacedotcom, Facebook and Google+. Original article on Space.com.

Look in the eastern sky for the next few nights and you will see a celestial treat.

Full moon was on Monday night (Oct. 29), so the waning gibbous moon will be rising a few hours past sunset. Jupiter, a month away from opposition on Dec. 2, will also be rising a few hours past sunset. The result will be what astronomers call a conjunction: a close encounter between two astronomical bodies.

The moon will be closest to Jupiter on Thursday night (Nov.1), but the two will also be close on Wednesday and Friday nights (Oct. 31 and Nov. 2).

The location of the moon relative to Jupiter will depend on your exact location because of something called parallax. [October 2012 Night Sky Observing Guide (Sky Maps)]

Hold a finger up at arm's length and look at a distant object. If you blink one eye and then the other, your finger will appear to jump from left to right. That's parallax, and it's what lets us view the world in three dimensions. Our two eyes are a couple of inches apart and each sees the world from a slightly different vantage. Our brains seemlessly integrate these two views into one three-dimensional picture, but if you close one eye at a time you can sense their different perspectives.

The same thing happens when people observe the moon against the starry backdrop from different spots on Earth: These slightly different perspectives create differing views.

In addition, the moon is revolving in its orbit around the Earth, causing it to appear to move from right to left against the background stars, including the planet Jupiter. Jupiter is moving too, but much more slowly than the moon, so its motion is not as obvious.

On Wednesday night, the moon will be well to the right of Jupiter, about halfway between two of the brightest and nearest star clusters, known by their ancient Greek names: the Pleiades and the Hyades.

To the unaided eye, the Pleiades looks like a tiny "dipper," except with only six stars instead of seven. It is located 410 light-years away, and contains hundreds of stars visible in binoculars or a small telescope.

The Hyades is closer to us, only 150 light-years distant, causing its stars to appear spread over a wider area of our sky.

On Thursday night, the moon will have moved to less than a degree away from Jupiter, so close that the two will fit together in the field of a telescope. For skywatchers in South Africa the moon will actually pass right in front of Jupiter, hiding it from view for over an hour in some locations, such as Cape Town.

By Friday night, the moon will be well to the left of Jupiter, not rising until around 9 p.m. local time.

Halloween is an excellent opportunity to do some "sidewalk astronomy." It's the one night in the year when there are lots of people out and about in a friendly family atmosphere.

If it's clear, set up your telescope and "share the view" with the trick-or-treaters. Impromptu Halloween star parties have become a tradition in some neighborhoods.

This article was provided to SPACE.com by Starry Night Education, the leader in space science curriculum solutions. Follow Starry Night on Twitter @StarryNightEdu.