Skywise! For October 2025
Every month we'll start with the brightest objects and work our way out to the dimmest objects. This method favors the easiest or most obvious targets. It also facilitates viewing under the most challenging skies first. The order will always be:
-Moon Phases
-Planets (the bright ones)
-Constellations
-Their Brightest Stars
-Constellations highlights listed by brightness
-Special Phenomena - eclipses, meteor showers, comets, and conjunctions
Every month we'll start with the brightest objects and work our way out to the dimmest objects. This method favors the easiest or most obvious targets. It also facilitates viewing under the most challenging skies first. The order will always be:
-Moon Phases
-Planets (the bright ones)
-Constellations
-Their Brightest Stars
-Constellations highlights listed by brightness
-Special Phenomena - eclipses, meteor showers, comets, and conjunctions
Comet Alert! - Comet Lemmon
You've heard the hype, now here's the lowdown.
Comet Lemmon is visible this month in the northwest evening sky, reaching its closest approach to Earth this week. It's just bright enough to be visible using binoculars under dark, clear skies. Comet Lemmon will not become a bright celestial spectacle. If you've never seen a comet before, it'll be tricky to spot. Images seen online use photography to create stunning images that our eyes cannot see.
How To Find Comet Lemmon
Your best chance of finding it comes Wednesday evening, Oct. 22nd, just after dark, when the comet will be close to a bright star in the constellation Bootes (pron. 'boo-OH-teez'). To find it, look to the northwest and locate the Big Dipper's handle. The handle's last star, Alkaid, points downward to Arcturus, the brightest star of Bootes. The Comet Lemmon locator star, Mirak, is the next brightest star above Arcturus. Now using binoculars, Lemmon is the fuzzy patch you see just to the left of Mirak. Take note of Lemmon's position and appearance next to Mirak because on following nights, Lemmon will be a short step farther to the left and a touch dimmer. Use this Stellarium starmap to locate Comet Lemmon's current position.
Happy comet hunting!
You've heard the hype, now here's the lowdown.
Comet Lemmon is visible this month in the northwest evening sky, reaching its closest approach to Earth this week. It's just bright enough to be visible using binoculars under dark, clear skies. Comet Lemmon will not become a bright celestial spectacle. If you've never seen a comet before, it'll be tricky to spot. Images seen online use photography to create stunning images that our eyes cannot see.
How To Find Comet Lemmon
Your best chance of finding it comes Wednesday evening, Oct. 22nd, just after dark, when the comet will be close to a bright star in the constellation Bootes (pron. 'boo-OH-teez'). To find it, look to the northwest and locate the Big Dipper's handle. The handle's last star, Alkaid, points downward to Arcturus, the brightest star of Bootes. The Comet Lemmon locator star, Mirak, is the next brightest star above Arcturus. Now using binoculars, Lemmon is the fuzzy patch you see just to the left of Mirak. Take note of Lemmon's position and appearance next to Mirak because on following nights, Lemmon will be a short step farther to the left and a touch dimmer. Use this Stellarium starmap to locate Comet Lemmon's current position.
Happy comet hunting!
Moon Phases for October 2025
Oct. 6 - Full Moon (Harvest Moon - first full moon following Autumnal Equinox, Supermoon)
Oct. 14 - Last Quarter
Oct. 21 - New Moon
Oct. 28 - First Quarter Moon
Oct. 6 - Full Moon (Harvest Moon - first full moon following Autumnal Equinox, Supermoon)
Oct. 14 - Last Quarter
Oct. 21 - New Moon
Oct. 28 - First Quarter Moon
Planets for October 2025
Venus is quite bright as a pre-dawn object well up in the East as the month starts, but incrementally sinks towards the horizon each morning. A very thin crescent moon slides past Venus, 30 minutes before sunrise Oct. 18th and 19th. look to the east and find super-bright Venus. The thin, waning crescent moon will be just to the right of Venus.
Mars begins the month very low in the West and sinks quickly out of view.
Jupiter rises around midnight as the month begins and is high in the Southeast by dawn. The moon rises with Jupiter on Oct. 14.
Saturn becomes easily visible above the Southeast horizon as the sun sets. It sets a few hours before sunrise. The moon slides past on Oct. 6.
Mercury is typically too close to the Sun for safe viewing. Uranus, Neptune, and Pluto are extremely dim, as you might expect, and are best seen with a telescope.
Venus is quite bright as a pre-dawn object well up in the East as the month starts, but incrementally sinks towards the horizon each morning. A very thin crescent moon slides past Venus, 30 minutes before sunrise Oct. 18th and 19th. look to the east and find super-bright Venus. The thin, waning crescent moon will be just to the right of Venus.
Mars begins the month very low in the West and sinks quickly out of view.
Jupiter rises around midnight as the month begins and is high in the Southeast by dawn. The moon rises with Jupiter on Oct. 14.
Saturn becomes easily visible above the Southeast horizon as the sun sets. It sets a few hours before sunrise. The moon slides past on Oct. 6.
Mercury is typically too close to the Sun for safe viewing. Uranus, Neptune, and Pluto are extremely dim, as you might expect, and are best seen with a telescope.
October Constellations
October is a fine month to pull together your knowledge of the night sky. The sky darkens earlier now and the evening temps are still pleasant. To get yourself properly oriented for sky viewing, check out my "How To" corner under the "Resources" tab above.
Let's start at 8:30p, looking almost directly overhead, top of the sky. Look for five bright-ish stars outlining a big cross, oriented North-South. That's the Northern Cross, proper name - Cygnus(SIG-nuss). It's one of the brightest star shapes of the season and it leads us to other bright star groups. The brightest star of Cygnus is called Deneb and is at the head of the cross. The star at the foot - Albireo - is a bit dimmer and the crossbar stars are Gienah, Sadr, and Delta. Deneb is 2,600 light years away. Albireo, just 433 light years away, is an optical double star with one blue star and one gold star; they look like they're right next to each other but they are actually quite far apart but close to our line of sight.
To the right of Cygnus(west) is the bright star Vega, brightest of the Lyra constellation. Vega is 100 times closer than Deneb but the two look similar in brightness. Shouldn't Vega be much brighter? Not if Deneb is so large and so bright that even at 100 times the distance it nearly outshines Vega!
Below Cygnus, towards the south horizon, you'll see another bright star almost as bright as the other two. This is Altair, the brightest star of the constellation Aquila. Altair is even closer than Vega, only 16 light years distance, but it looks nearly the same brightness as the other two bright stars. How? If all three were set next to each other and at the the distance of Vega, neither star would be visible in the presence of Deneb. Deneb is about 108 times the diameter of our Sun!
One constellation farther to the right, west, beyond Lyra, we find four not so bright stars that make the body box of Hercules, the leader of the summer constellation group. Hercules is home to a dense gathering of stars called a globular cluster. Made up of 100,000+ gravitationally-bound stars, globulars are the oldest members of our galaxy and form an extended sphere around the core of the galaxy. You'll need a pair of binocs to see this fuzzy sphere of stars under clear, dark skies. Not gonna lie, it's virtually impossible to see from anywhere near nighttime city lights. Use stellarium-web.org/
to locate Hercules, the cluster and any other star groups.
Let's go back to Cygnus and look to the left (East) of the Cross where we'll find the leader of the Fall constellations group, Pegasus. This one is also four stars marking the corners of a box, but this box is much bigger. It's not the box we want but really the star at the top left corner of the box. That one - Alpheratz - connects to another star group, Andromeda, where we can find the next closest spiral galaxy to ours, the Andromeda galaxy. You'll need binocs and dark sky for this one also. The softly glowing patch of light may not look impressive but that's what we look like from Andromeda - 350 billion stars all spinning around a supermassive black hole at the center! this is the most distant object we can see without a telescope. Here's the mind-blowing part: the light we see tonight left Andromeda 2.9 million years ago! Amazing.
Now let's get back to something more familiar and more easily visible.
What's the best known star shape in the night sky? Yep, the Big Dipper! During this time of year, the Big Dipper is almost directly north and right down on the horizon. Its seven bright stars are all bright enough to be easily seen in almost all night light situations. If you have those binocs handy, take a look at the second star in the handle of the dipper. How many stars to you see? Look for two. This is a famous double star named Mizar and Alcor, the first double star pair ever known. They are gravitationally bound to each other such that Alcor orbits around Mizar once every 750,000 years. Even more amazing is that Mizar itself is a double double and Alcor has been identified as a double, so there are six stars in the group altogether!
Eclipses, Meteor Showers, Comets and Conjunctions
There are no eclipses this month but the next set of eclipses comes in 2026:
Feb. 17: Annular Solar - Antarctica, partial in Africa, S. America and surrounding oceans
March 3: Total Lunar - Western Hemisphere
August 12: Total Solar – Greenland, Iceland, Spain, Russia; partial N. America, Europe, Africa
August 27-28: Partial Lunar – Eastern Americas, Europe, Africa, Western Asia
The Orionid Meteor Shower peaks on the night of Oct. 20-21. The Orionids is what I refer to as one of the year's secondary showers; not very prolific. If you should see a few, gee that's nice. This year, the moon is at new phase so the night sky will be moonless. The peak hourly rate for a group of observers under clear, dark skies, is 10-30 per hour. The best time to view is between midnight and sunrise (Oct. 20-21) as the Earth is turning into this stream of dust left over from Halley's Comet. If you can't do the graveyard shift, the sand-grain sized particles will start to show as soon as the sky gets dark and the path of the streaks will trace back over to the eastern sky where the namesake constellation will rise around 11p. Although small, the meteors will streak quickly through the Earth's upper atmosphere, blasting in at 148,000mph! Slamming the atmosphere at that speed will reduce them to dust in the blink of an eye! For a more prolific shower, stay tuned for the Geminids in December!
There are no eclipses this month but the next set of eclipses comes in 2026:
Feb. 17: Annular Solar - Antarctica, partial in Africa, S. America and surrounding oceans
March 3: Total Lunar - Western Hemisphere
August 12: Total Solar – Greenland, Iceland, Spain, Russia; partial N. America, Europe, Africa
August 27-28: Partial Lunar – Eastern Americas, Europe, Africa, Western Asia
The Orionid Meteor Shower peaks on the night of Oct. 20-21. The Orionids is what I refer to as one of the year's secondary showers; not very prolific. If you should see a few, gee that's nice. This year, the moon is at new phase so the night sky will be moonless. The peak hourly rate for a group of observers under clear, dark skies, is 10-30 per hour. The best time to view is between midnight and sunrise (Oct. 20-21) as the Earth is turning into this stream of dust left over from Halley's Comet. If you can't do the graveyard shift, the sand-grain sized particles will start to show as soon as the sky gets dark and the path of the streaks will trace back over to the eastern sky where the namesake constellation will rise around 11p. Although small, the meteors will streak quickly through the Earth's upper atmosphere, blasting in at 148,000mph! Slamming the atmosphere at that speed will reduce them to dust in the blink of an eye! For a more prolific shower, stay tuned for the Geminids in December!