The Ones That Arrived

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Small objects enter the atmosphere constantly. Most burn up tens of kilometres above the ground and are seen by nobody. Since 1988, government sensors watching the whole sky for other reasons have recorded the brighter ones, and NASA/JPL publishes what they saw.

Largest Recorded

887 entries recorded with a location, showing 60. Sorted by energy. Show most recent instead.

NASA/JPL CNEOS fireball database, fetched 2026-10-03 11:10 UTC. Energy is the total impact energy in kilotons of TNT equivalent; one kiloton is a bright fireball, not an explosion on the ground. Altitude is where the brightness peaked.

What the Numbers Mean

The largest entry in the database by a wide margin is 15 February 2013 over Chelyabinsk, at roughly 440 kilotons — an object about twenty metres across that broke up some thirty kilometres up. The damage on the ground came almost entirely from the shock wave breaking windows, and nobody saw it coming: it arrived from the direction of the Sun, where no telescope can look.

Everything else in the list is far smaller. Energy on a logarithmic plot makes that hard to feel, so put it plainly: the great majority are under one kiloton, which means a bright light in the sky and perhaps a few fragments reaching the ground as meteorites. The population is heavily tilted towards the small, and that is the normal state of affairs rather than a lucky period.

Note also what the list is not. It records detected events. Most of the planet is ocean and the sensors do not catch everything, so the real arrival rate is higher than the count here — and the geographic spread says more about coverage than about where asteroids prefer to land.

Seen Before They Arrived

A much shorter list, and the one that shows the detection systems working. Only about a dozen objects have ever been discovered in space and then tracked all the way to an atmospheric entry predicted in advance, usually with a few hours' notice. The first was 2008 TC3, found about twenty hours before it entered over Sudan in October 2008; fragments were later collected in the desert, which made it also the first object whose meteorites could be matched to a telescopic observation of the parent body.

Every one of them has been small — metres rather than tens of metres. That is not a coincidence: small objects are faint until they are very close, so they are found late, while anything large enough to be dangerous is usually found years ahead. The warning time is short precisely because the object is harmless. The count rises every year or two as surveys improve, which is the trend worth watching rather than any individual entry.

Jupiter, and Why Not Saturn

Jupiter is struck far more often than Earth — it is much larger and its gravity draws objects in. The famous case is Shoemaker–Levy 9, a comet pulled apart by Jupiter's tides and observed striking the planet in fragments over several days in July 1994, leaving dark scars visible in small telescopes for months. It remains the only impact on another planet ever observed as it happened from start to finish, and it was predicted in advance.

Since 2009, a series of briefer flashes has been recorded on Jupiter, most of them caught by amateur astronomers recording video of the planet and noticing a point of light lasting a second or two. These are small objects, and the detections depend on somebody happening to be filming — which is why the rate we observe says more about how many people point cameras at Jupiter than about how often it is hit.

Saturn has no comparable record. No impact has been observed in progress there. What exists instead is indirect: patterns in the rings, read as the long-lived ripples left by a debris cloud passing through, which imply an impact decades ago rather than showing one. Saturn is further away, fainter, and far less watched, so absence of observation is not absence of impacts.

There is no public feed for either, unlike everything above — planetary impact observations are individual published results, not a database. This section is written rather than fetched, and it will not update itself.