🌠 How to See a Comet Tonight Over Phoenix — Your Binocular Guide to the October Sky

Last Updated on October 18, 2025 by Daily News Staff

Phoenix skywatchers are in for a treat tonight as not one, but two comets — C/2025 A6 (Lemmon) and C/2025 R2 (SWAN) — make their way across the evening sky. Both are now bright enough to be seen through a good pair of binoculars, and one may even flirt with naked-eye visibility under dark conditions.

If you’ve ever wanted to catch a comet without fancy equipment, tonight’s your chance.

🌌 What You’ll See

Comet Lemmon (C/2025 A6) has been gaining brightness through October and now glows with a faint greenish hue, a sign of vaporized gases and carbon compounds in its tail. Under Phoenix’s clear skies, you may spot it as a fuzzy, glowing patch — brighter than most surrounding stars when viewed through binoculars.

The second visitor, Comet SWAN (C/2025 R2), is also within binocular range, adding to this rare double-comet spectacle. Though smaller and dimmer than Lemmon, it’s still worth the hunt.

🕗 When and Where to Look

• Best viewing time: About 30–60 minutes after sunset (roughly between 7:00 and 7:30 PM in Phoenix).
• Comet Lemmon: Look toward the northwest to west horizon, about midway between the bright star Arcturus and the handle of the Big Dipper.
• Comet SWAN: Scan the southwest sky, just above where the Sun has recently set.

Both comets will be low on the horizon, so find an open spot with no buildings or trees blocking your view.

🔭 Tips for Best Viewing

• Use binoculars (7×50 or 10×50 are ideal).
• Step away from bright city lights — South Mountain, Papago Park, or the outskirts of Phoenix offer better visibility.
• Allow your eyes 10–15 minutes to adjust to darkness.
• Bring a stargazing app (like Sky Tonight or Star Walk 2) and search the comet names to track them in real-time.
• If you have a tripod, use it — even slight hand movements can blur the view.

🌙 What to Expect

Comets aren’t as bright or defined as the ones we see in movies. Through binoculars, expect a small, glowing orb with a hint of a tail — especially for Lemmon. As the comet continues to approach the Sun in late October, it may brighten even further.

For many observers, simply knowing you’re seeing an object that’s traveled millions of miles through space makes the experience unforgettable.

⚠️ A Few Things to Note

• Visibility can change night to night depending on brightness, weather, and moonlight.
• If clouds or haze roll in, try again over the next few evenings — both comets will remain visible for several more nights.
• Don’t be discouraged if you don’t spot it immediately — comet hunting takes patience, but the reward is worth it.

📸 Share the Moment

If you manage to snap a photo of Comet Lemmon or SWAN from Phoenix, tag @stmdailynews on social media and use #STMSkyWatch — we might feature your photo in an upcoming article.

For more astronomy updates, local skywatching events, and science news, visit STM DailyNews Astronomy.

About the Comets

• How to See Rare Comet Lemmon During Its Once-in-a-Lifetime Visit – People
• Comet Lemmon: How and When to Watch – Wired
• Two Bright, Once-in-a-Lifetime Comets Visible This Month – Washington Post
• Comet Lemmon Shines in October Skies – Astronomy.com
• How to See Comet SWAN (C/2025 R2) in October – Space.com
• Comet SWAN 2025: What to Expect – EarthSky.org

Skywatching Tools

• Sky Tonight – Stargazing App (App Store)
• Star Walk 2 – Interactive Astronomy Guide
• Heavens-Above: Current Comet Positions

For Phoenix Skywatchers

• Phoenix Clear Sky Chart – Weather for Astronomers
• Phoenix Light Pollution Map – Dark Site Finder
• Arizona Science Center – Astronomy Events