Can I see the ISS transit the Moon with the naked eye?

Barely — it is fast and small. Most people catch it with binoculars or a telescope, or by filming the Moon at high frame rate and finding the silhouette frame by frame. A safe solar filter is required for the daytime Sun version; the Moon needs no filter.

The Moon · Sky tonight

See the ISS cross the Moon

Q: What is an ISS lunar transit?

An ISS lunar transit is when the International Space Station passes directly between you and the Moon, appearing as a small dark silhouette crossing the Moon's face. Because the station moves at about 28,000 km/h, the crossing lasts only 0.5 to 1 second.

Q: How often can I see the ISS cross the Moon?

Transits happen somewhere on Earth often, but the narrow shadow path is usually only a few kilometres wide, so from any fixed spot a visible ISS lunar transit is rare — often months apart. You typically need to travel a short distance to stand inside the transit path.

Q: Is the black dot crossing the Moon a UFO?

No. A dark, fast dot crossing the Moon in under a second is almost always the ISS or another large satellite in silhouette. It is predictable and trackable — a live satellite tracker will confirm the station's position over you.

Q: How do I photograph an ISS lunar transit?

Set up on the Moon well before the predicted time, use a telephoto lens or telescope with a fast shutter (1/1000s+) and burst or high-frame-rate video, and start recording several seconds before transit. Precise timing to the second — from a transit predictor — is essential.

An ISS lunar transit is the International Space Station passing directly in front of the Moon — a tiny dark silhouette that races across its face in under a second. It's one of the most striking things you can catch in the night sky, it's completely predictable, and no — that fast black dot on the Moon isn't a UFO. Here's what it is, how to catch one over your location, and how to photograph it.

The International Space Station silhouetted as a tiny dark shape crossing the face of the full Moon

~0.6 sHow long a transit lasts

28,000 km/hISS orbital speed

~400 kmISS altitude

few kmWidth of the transit path

🛰️ Track the ISS over your location →

🌙What an ISS lunar transit actually is

The Moon is about 384,000 km away; the ISS orbits just ~400 km up. When the station passes directly on the line between your eye and the Moon, you see it in silhouette — a sharp little dark shape (you can often make out the solar panels) sliding across the bright lunar disc. Because the ISS is moving at roughly 28,000 km/h, the whole crossing is over in about half a second. Blink and you miss it.

Why it's not a UFO: a dark dot that crosses the Moon in a fraction of a second, on a perfectly straight path, is a large satellite in silhouette — almost always the ISS. It's 100% predictable from orbital data, which is exactly why transit predictors and live trackers exist.

✅How to catch one — step by step

Find a transit near you. Use a transit predictor (search "ISS transit finder") — it maps the narrow ground path where the silhouette is visible, usually only a few kilometres wide.
Confirm the ISS pass with a live tracker. Open the SkyLens tracker to see where the station is and when it's overhead — handy for lining up the timing.
Get inside the path. You often need to drive a short distance to stand on the exact line. A few hundred metres off and you'll miss the silhouette.
Set up on the Moon early. Point binoculars or a telescope (or a telephoto lens) at the Moon minutes ahead — the Moon needs no filter.
Record continuously. Shoot high-frame-rate video or a fast burst starting several seconds before the predicted time — then find the silhouette frame by frame. Timing to the second is everything.

📸Photographing the transit

A telephoto lens (300 mm+) or a small telescope, a fast shutter (1/1000 s or faster), and burst/high-fps video are the winning combo. The ISS is only a few arc-minutes across against the Moon, so you're relying on precise timing, not luck. The most reliable method: film the whole Moon at 60–120 fps for ten seconds around the predicted time, then scrub through for the two or three frames that catch the station.

Prefer the naked-eye experience? You'll more easily see the ISS as a bright steady light passing near the Moon on many nights — here's how to catch a normal ISS pass tonight.

❓Frequently asked questions

What is an ISS lunar transit?

The ISS passing directly between you and the Moon, appearing as a small dark silhouette crossing the Moon's face. At ~28,000 km/h it lasts only 0.5–1 second.

How often can I see the ISS cross the Moon?

Transits happen often somewhere on Earth, but the visible path is only a few km wide, so from a fixed spot they're rare — often months apart. You usually travel a short way to stand in the path.

Can I see it with the naked eye?

Barely — it's fast and small. Most people use binoculars, a telescope, or high-frame-rate video and find the silhouette frame by frame.

Is the black dot crossing the Moon a UFO?

No — a fast, dark dot crossing the Moon in under a second is the ISS or another large satellite in silhouette. It's predictable and trackable.

How do I photograph an ISS lunar transit?

Set up on the Moon early, use a telephoto/telescope with a fast shutter (1/1000s+) and burst or high-fps video, and start recording several seconds before the predicted second.

ISS position on SkyLens comes from the public CelesTrak catalog, propagated with SGP4. Independent educational platform — not affiliated with any government agency.