Does NASA have an asteroid tracker?

Yes. NASA's Center for Near-Earth Object Studies publishes close approach data and maintains the Sentry impact monitoring system. Orbitfall reads NASA's Near Earth Object Web Service and presents the same data in a readable ranked view.

Is Orbitfall official NASA software?

No. Orbitfall is an independent tracker built on NASA's public API. All measurements come from NASA; the Orbitfall Index ranking is ours.

How often does the asteroid data update?

The NASA feed is queried live on each page load, and NASA's underlying orbit solutions are refined whenever new observations arrive.

NASA Asteroid Tracker

Orbitfall reads NASA's near-Earth object data directly and turns it into a ranked, readable list of asteroid close approaches.

NASA does not publish a single consumer-facing "asteroid tracker" app. What it publishes is data: the Center for Near-Earth Object Studies (CNEOS) at JPL computes orbits for every catalogued near-Earth object and exposes the resulting close approach tables through public tools and an API. Orbitfall is a reader for that data.

The data source

Every number in the tracker comes from NASA's Near Earth Object Web Service (NeoWs). For a given date window, the feed returns each catalogued object with its close approach records, and Orbitfall flattens that into one row per approach containing:

object name and NASA/JPL reference ID
close approach date and time
miss distance in kilometres, astronomical units and lunar distances
relative velocity in kilometres per second
estimated diameter range in metres, from absolute magnitude
whether NASA flags the object as potentially hazardous

Nothing is modelled or estimated on our side. The only value Orbitfall adds is the Orbitfall Index, a 0–100 ranking that combines proximity, size, velocity and the hazard flag so the most notable pass surfaces first. This score ranks how notable the asteroid approach is. It is not an impact prediction.

How NASA builds the numbers

A new object is usually found by a survey telescope — Pan-STARRS, Catalina, ATLAS — as a moving dot across a few frames. Those positions go to the Minor Planet Center, which links them to a provisional designation. CNEOS then fits an orbit and propagates it forward, producing the close approach predictions the API serves. More observations mean a tighter orbit and a sharper prediction, which is why distances for newly found objects can shift more than for ones catalogued years ago. The longer version is in how NASA tracks asteroids.

What a tracker can and cannot tell you

A close approach list is a schedule of known flybys, not an early warning system. Impact risk is handled separately by CNEOS's Sentry system, which continuously screens catalogued objects for any non-negligible impact probability over the next century. Orbitfall does not reproduce Sentry, does not compute impact probabilities, and should not be read as an impact-warning service. See what a close approach means.

Start tracking

Open the Orbitfall tracker for the full sortable view, or jump to asteroids passing Earth today, asteroids passing Earth this week, or near-Earth objects today. Details on the ranking live on the methodology page.

Frequently asked questions

Does NASA have an asteroid tracker?: Yes. NASA's Center for Near-Earth Object Studies publishes close approach data and maintains the Sentry impact monitoring system. Orbitfall reads NASA's Near Earth Object Web Service and presents the same data in a readable ranked view.
Is Orbitfall official NASA software?: No. Orbitfall is an independent tracker built on NASA's public API. All measurements come from NASA; the Orbitfall Index ranking is ours.
How often does the asteroid data update?: The NASA feed is queried live on each page load, and NASA's underlying orbit solutions are refined whenever new observations arrive.

Asteroid guide