Astronomical Events in October 2025: Comets Take Center Stage
October is shaping up to be an unforgettable month for stargazers! This month has everything: three spectacular comets, the year's first Supermoon, bright meteors, dazzling conjunctions, and more. With so many celestial events happening, all you need is our free Sky Tonight app to easily track celestial objects. Whether you're a seasoned observer or a beginner, October offers the perfect opportunity to explore the night sky. Let's dive into what October has in store for us!
Contents
- October Celestial Events Calendar: What’s Up in the Sky This Month
- October 2025 Is A Month of Comets
- Lunar Events in October 2025
- Planets in the Sky – October 2025
- Best Constellations – October 2025
- Shooting Stars in October 2025: Meet Seven Meteor Showers
- October 4-10: Celebrate World Space Week & Get a Cosmic Gift!
- Bottom Line: October Sky Events 2025
October Celestial Events Calendar: What’s Up in the Sky This Month
Event dates are listed in GMT (Greenwich Mean Time). For your location, they may differ due to different time zones. To find out the exact time and date of an event in your city, use the Sky Tonight app.
- October 2: Ceres (mag 7.6) at opposition, Mercury (mag -0.5) near Spica (mag 1);
- October 5: October Camelopardalids’ peak (ZHR=5);
- October 6: Saturn (mag 0.6), and Neptune (mag 7.8) near Moon;
- October 7: Supermoon 🌟;
- October 8: C/2025 K1 (ATLAS) passes perihelion 🌟; Draconids’ peak (ZHR=5);
- October 10: Moon near Aldebaran (mag 0.8); lunar occultation of the Pleiades (mag 1.6); Uranus (mag 5.6) near Moon;
- October 11: Delta Aurigids’ peak (ZHR=2); Jupiter (mag -2.2) near Pollux (mag 1.2);
- October 13: Southern Taurids’ early activity (ZHR=5); Jupiter (mag -2.2) near Moon; Pollux (mag 1.2) near Moon; Last Quarter Moon;
- October 14: Moon near the Beehive Cluster (mag 3.1);
- October 16: Lunar occultation of Regulus (mag 1.4);
- October 18: Epsilon Geminids’ peak (ZHR=3);
- October 19: Mercury (mag -0.2) near Mars (mag 1.4); Venus (mag -3.9) near Moon;
- October 20: C/2025 R2 SWAN passes perigee 🌟;
- October 21: Orionids’ peak (ZHR=20) 🌟; New Moon; C/2025 A6 (Lemmon) passes perigee 🌟;
- October 23: Mercury (mag -0.2) and Mars (mag 1.4) near Moon;
- October 24: Leonis Minorids’ peak (ZHR=2); lunar occultation of Antares (mag 1.0);
- October 29: Comet 3I/ATLAS passes perihelion 🌟; First Quarter Moon; Mercury (mag −0.1) at greatest eastern elongation (≈ 24° from the Sun) 🌟.
*The highlighted events are the most interesting events of the month.
About magnitude: the faintest magnitude for stars and planets visible to the naked eye in cities with moderate light pollution is about 4. The limiting magnitude of an optical device depends on its specification but rarely exceeds 11.
October 2025 Is A Month of Comets
October 2025 promises to be a comet-hunter’s dream, with three different comets making newsworthy appearances.
The first is Comet C/2025 K1 (ATLAS), which will reach perihelion on October 8. If it survives its close approach to the Sun, it could reach a magnitude of 5.2, making it visible through binoculars. Those in the Northern Hemisphere will have the best view in the morning sky, while observers in the Southern Hemisphere can see it in both the morning and evening.
Comet C/2025 R2 (SWAN), discovered at the beginning of September, is another highlight. It will make its closest approach to Earth on October 20, at just 0.26 AU. The comet has a magnitude of 7. If it continues to brighten, it may become visible to the naked eye under dark skies around October 20. It is best seen from the Southern Hemisphere, but northern stargazers should start spotting it low in the evening sky in mid-October.
Finally, Comet C/2025 A6 (Lemmon) comes into play later in the month. On October 21, it will pass just 0.6 AU from Earth and could reach a magnitude of 8, making it visible with binoculars. Some optimistic forecasts suggest that it could brighten to a magnitude of 3 near its perihelion on November 8, making it an easy target for the naked eye.
Grab your camera for a double treat! On October 19, Comets SWAN and Lemmon will be visible in the sky together, separated by 80°. Don’t miss this celestial date!
Read more: Upcoming Comets
Track Comets Like a Pro
Comets often appear as faint, blurry smudges in the sky, so knowing their exact position is crucial. The Sky Tonight app makes this simple:
- Tap the magnifier icon at the bottom of the screen.
- Type the comet’s name or designation in the search bar.
- From the results, tap the blue target icon next to the name of the needed comet — the app will take you straight to its position in the sky.
- Hold up your device and follow the white arrow to locate the comet.
For more details, tap the comet’s name in the search results and open the Events tab. There you’ll see important dates like perihelion or closest approach to Earth. Tap on the event to learn even more about it.
Lunar Events in October 2025
Moon Phases in October 2025
- Full Moon: October 7, 03:48 GMT
- Last Quarter: October 13, 18:13 GMT
- New Moon: October 21, 12:25 GMT
- First Quarter: October 29, 16:21 GMT
Check our comprehensive lunar calendar, where you can easily track the Moon phase for any date. Plan your stargazing adventures with precise moonrise and moonset times, all in one convenient place.
You can also find out the Moon’s phase, brightness, location, and other details in the Moon calendar of the Sky Tonight astronomy app. Just open the app, tap the calendar icon at the bottom of the main screen, and go to the “Moon” tab to get all the up-to-date information about our natural satellite. The images of the Moon in the calendar correspond to the actual appearance of the Moon on that day.
Harvest Full Moon on October 7 – First Supermoon of 2025
On October 7, at 03:48 GMT, skywatchers will see the Harvest Full Moon, which also happens to be the first Supermoon of the year.
The Harvest Moon is simply the Full Moon closest to the autumnal equinox. In the Northern Hemisphere, it typically falls in September, but every few years, it shifts to October – as seen in 2025. The last October Harvest Moon was in 2020, and the next won’t happen until 2028. For the Southern Hemisphere, the Harvest Moon typically occurs in March or April, with the next one scheduled for April 2, 2026.
In 2025, the October Full Moon occurs near perigee, its closest point to Earth, making it a Supermoon. It will appear about 6.6% larger and 13% brighter than an average Full Moon. While that sounds impressive, the size difference is barely noticeable to the naked eye. If you really want the Moon to look huge, here’s a trick: watch it as it rises or sets near the horizon. Thanks to the Moon illusion, it will appear much larger than when it’s high in the sky.
Want to know when the next Supermoons are and what they mean? Explore our infographic on Supermoons and Micromoons!
New Moon on October 21 – Dark Skies for the Orionids & Comet Lemmon
On October 21, 2025, at 12:25 GMT, the New Moon will bring the darkest skies of the month – perfect conditions for stargazing. With no bright moonlight to interfere, this night offers an ideal chance to enjoy the Orionid meteor shower, which peaks between midnight and dawn. At the peak, you may spot up to 20 meteors per hour, streaking across the sky from the constellation Orion.
But that’s not all. The same night, Comet C/2025 A6 (Lemmon) will make its closest approach to Earth at 0.6 AU. In the Northern Hemisphere, it will be conveniently placed for observations in the evening sky above the northwest horizon, near the Big Dipper. Optimistic predictions suggest it could brighten to magnitude 4, making it visible to the naked eye from dark locations and a fine target for binoculars.
Read more: Orionid Meteor Shower, Comet Lemmon
More photo-worthy lunar events in October 2025
October brings not only comets and meteors but also several beautiful close approaches of the Moon to bright planets and stars.
October 19 – Moon and Venus
On October 19, at 18:41 GMT, the waning crescent Moon (3% illuminated) will pass within 3°48′ of Venus (mag -3.9) in Virgo. Later, at 21:00 GMT, they’ll reach the conjunction, separated by 4°00′. Venus will be dazzlingly bright and easy to spot with the naked eye, while the thin Moon will be more challenging but still rewarding to catch in the morning twilight.
October 23 – Moon, Mercury, and Mars
From around October 19, Mercury (mag -0.2) and Mars (mag 1.4) will be seen together in the evening sky, at a distance as close as 2°07′. On October 23, the waxing crescent Moon will join the planetary pair. This celestial meet-up is hard to catch, so be sure you have a clear, open horizon. Look for the lunar crescent (3% illuminated), Mars, and Mercury on the south-western horizon after sunset in the constellation Libra.
October 24-25 – Moon and Antares (with occultation)
On the night of October 24-25, the 11%-lit Moon will pass very close to Antares (mag 1.0), the fiery red heart of Scorpius. The closest approach occurs on October 25 at 00:46 GMT, when the two will be just 0°30′ apart.
Even better, observers in southern Argentina, Chile, and the Falkland Islands will see a lunar occultation of Antares, when the Moon will cover and then reveal the star. The occultation takes place from 22:45 GMT on October 24 to 00:46 GMT on October 25. Elsewhere, the close pairing will still be a beautiful sight, perfect for binoculars or a telephoto lens.
Read more: What Planet Is Near the Moon Tonight?
Planets in the Sky – October 2025
Planets Visible in the Northern Hemisphere – October 2025
Mercury (Virgo, Libra, Scorpius): Hidden in solar glare for most of the month. By late October, begins to appear very low above the southwestern horizon after sunset. Reaches the greatest eastern elongation on October 29, becoming easier to spot. Fades slightly from magnitude -0.5 to -0.2.
Venus (Leo, Virgo): Shines as the bright “Morning Star” low in the eastern sky at magnitude -3.9. Best seen shortly before sunrise.
Mars (Virgo, Libra): Too close to the Sun to be observed. May be glimpsed for no more than half an hour after sunset, low in the southwestern sky. Slightly dims from magnitude 1.6 to 1.5.
Jupiter (Gemini): Rises after midnight in early and mid-month, and by late October, becomes visible through the night until dawn. Brightens slightly from magnitude -2.1 to -2.3, an excellent target for naked-eye and telescopic views.
Saturn (Pisces, near Aquarius): Still well-placed after its September opposition. Visible in the evening and first half of the night, glowing steadily at magnitude 0.7 to 0.9. The shortening days and longer nights make viewing conditions favorable.
Uranus (Taurus): Rises in the early evening and remains visible throughout the night by late October. Too faint for the naked eye, but binoculars or a telescope easily reveal it. Has a magnitude of 5.6.
Neptune (Pisces): Visible in the evening and night sky. Has a magnitude of 7.8 and requires binoculars or a telescope to spot.
Planets Visible in the Southern Hemisphere – October 2025
Mercury (Virgo, Libra): Visible briefly after sunset, very low above the western horizon. Best seen around October 29, when it reaches its greatest eastern elongation. Shines at magnitude -0.4 but remains tricky to spot without a clear view to the horizon.
Venus (Leo, Virgo): Appears as the dazzling Morning Star low on the eastern horizon at dawn. Shines bright and steady at magnitude -3.9.
Mars (Libra): Can be spotted in the western evening sky, glowing faintly at magnitude 1.5. Hangs low above the horizon and is not a standout object this month.
Jupiter (Gemini): Visible in the northern sky before sunrise, shines bright at magnitude -2.0. A reliable and easy-to-spot planet for morning observers.
Saturn (Pisces, near Aquarius): Still well-placed after its September opposition. Visible in the evening and night sky, shining at magnitude 0.6 to 0.7.
Uranus (Taurus): Rises in the evening and remains visible late at night and in the early morning. Too faint for the naked eye, but binoculars or a telescope easily reveal it. Has a magnitude of 5.6.
Neptune (Pisces): Visible in the evening and night sky at magnitude 7.8. Requires binoculars or a telescope to observe.
Mercury Greatest Elongation on October 29 – Best Time to See the Planet
On October 29, at 21:59 GMT, Mercury will reach its greatest eastern elongation, appearing 23° 54′ away from the Sun in the sky. This is the best time to observe the elusive planet, which usually hides in the Sun’s glare. Shining at a magnitude of -0.1, Mercury will be visible just after sunset in the constellation Libra.
Although the greatest elongation always marks the planet’s prime viewing window, not all elongations are equal. This one favors the Southern Hemisphere, where Mercury will appear noticeably higher above the horizon. In the Northern Hemisphere, the planet will sit lower and require a very clear western horizon for a good view.
Read more: What Is Elongation in Astronomy?
Bonus: Dwarf Planet Ceres at Its Brightest on October 2
On October 2, at 13:12 GMT, the dwarf planet Ceres will reach opposition, marking the best time of the year to observe this small object. At opposition, Ceres will shine at its brightest, though still not bright enough to see with the naked eye. Ceres is the smallest dwarf planet in the Solar System, but it’s also the closest to Earth, which means that, unlike Pluto or Eris, it can actually be spotted with modest equipment.
During opposition, Ceres will lie in the constellation Cetus, remaining visible for much of the night and reaching its highest point around midnight local time. At a magnitude of 7.5, Ceres can be seen through 8x40 or 10x50 binoculars, making it a rare treat for casual skywatchers.
If you manage to spot it, you’ll be adding a dwarf planet to your stargazing achievements – something not many observers can claim. Don’t miss this opportunity!
Read more: What Is Opposition in Astronomy?
Best Constellations – October 2025
October evenings bring a rich mix of constellations. In the Northern Hemisphere, look for the zodiac constellations Pisces, Aquarius, and Capricornus. High overhead, you can easily find Pegasus*, leading to Andromeda, and nearby Cepheus. You can also get the last glimpse of the Summer Triangle (Cygnus, Lyra, and Aquila).
In the Southern Hemisphere, the zodiac constellations Pisces, Aquarius, Capricornus, and Sagittarius dominate the evening skies, joined by the large sea-creature Cetus. Southern observers are also treated to constellations unseen in the north, such as the elegant Grus, the fainter Octans near the south celestial pole, and Piscis Austrinus, marked by the bright star Fomalhaut.
Read more: October Constellations
Shooting Stars in October 2025: Meet Seven Meteor Showers
In October, seven meteor showers will reach their maximum activity.
The month starts with the peak of the October Camelopardalids (ZHR=5) on October 5, though bright moonlight will wash out most of their faint meteors.
Just a few days later, the Draconids (ZHR=5) peak on October 8. The nearly Full Moon will make the observing conditions very poor, but this meteor shower is famous for surprise outbursts. Some forecasts suggest a brief outburst of activity between 15:00 and 16:00 GMT, with rates possibly reaching 100-150 meteors per hour. The Draconids are best seen from the Northern Hemisphere east of 40°E longitude.
On October 11, the peak of the Delta Aurigids follows with only 2 meteors per hour, also hindered by moonlight.
A better show comes with the peak of the Southern Taurids on October 13, when the half-lit Moon allows for modest viewing of about 5 meteors per hour from both hemispheres.
The Epsilon Geminids on October 18 also benefit from dark skies, with 3 meteors per hour during the peak visible in both hemispheres, especially well in the north.
The real highlight for meteor hunters is the Orionids, peaking on the night of October 21 during the New Moon. With no moonlight interference, observers across both hemispheres can expect up to 20 swift, bright meteors per hour. The Orionid meteors are especially famous for leaving glowing trails behind.
Finally, the month closes with the peak of the Leonis Minorids on October 24. It’s a faint meteor shower providing only up to 2 meteors per hour, still worth trying to spot on the nearly moonless sky. This meteor shower favors the Northern Hemisphere.
Read more: October Meteor Showers
October 4-10: Celebrate World Space Week & Get a Cosmic Gift!
October is a special month for space-lovers! Every year from October 4 to 10, people around the world celebrate World Space Week, the largest international event dedicated to space science and technology. For 2025, the theme is “Living in Space,” which highlights humanity’s dream of making space a second home.
But World Space Week isn’t only about looking into the future — it’s also the perfect time to look up, whether you’re spotting the Orionids, tracking comets, or just admiring the Moon. And if you want to make your October stargazing even more fun, check our full article about the World Space Week — there’s even a special astronomy gift waiting for you!
Read more: World Space Week 2025
Bottom Line: October Sky Events 2025
In October 2025, you may see the first Supermoon of the year, the Orionid meteors on the moonless night, Mercury at greatest elongation, and even several bright comets. Add lunar encounters with planets and stars, brilliant constellations, and exciting deep-sky objects, and you’ll never be bored this month. Use the free Sky Tonight app to track all the celestial wonders and never miss a sky show!
