On the night of 5 February 2026 the Vera C. Rubin Observatory filed about 20,000 candidate asteroid discoveries at once, drawn from roughly 246,000 observations. Its entire previous haul, across 1.6 years of test observing, was 12,700.
On the night of 5 February 2026 a telescope in the Chilean Andes filed about 20,000 candidate asteroid discoveries in a single batch. They came from roughly 246,000 individual observations, and they went to the Minor Planet Center, the International Astronomical Union body that keeps the world's official register of asteroids and comets. The centre processed the lot. Across its previous 1.6 years of test observing, the same telescope, the NSF-DOE Vera C. Rubin Observatory, had found 12,700 asteroids in total.
How we know
The count comes from the Minor Planet Center's own newsletter for February 2026, which records the submission as approximately 20,000 candidate discoveries corresponding to roughly 246,000 individual observations, and states that the entire batch was processed. Rubin does not send in raw tracklets, the short runs of observations that catch one dot moving against the stars over a single night. It links them into candidate objects itself first, and does so deliberately conservatively, under a strategy the observatory and the centre worked out together to keep false matches out of the catalogue. Every tracklet that arrives is still checked against the orbits of objects already known before anything is designated as new. Data that comes in already linked would be slow through the standard route, so the centre built a separate pipeline for it and added a stage of manual vetting on top.
Rubin's own account of an earlier batch fills in what the objects are. About six weeks of early survey data produced more than 11,000 new asteroids, inside a submission of roughly a million observations that also covered more than 80,000 asteroids already on record. Among the new ones were 33 near-Earth objects, asteroids and comets on orbits that bring them close to Earth's own, the largest about 500 metres across. In under two months the same search turned up around 380 trans-Neptunian objects, the icy bodies that orbit out beyond Neptune, against roughly 5,000 found in the previous three decades. The software doing the finding was written at the University of Washington by Ari Heinze and Jacob Kurlander.
Why it matters
Planetary defence begins as a clerical problem. Nobody can deflect an asteroid that has not been found, and about 40 percent of the near-Earth objects wider than 140 metres are on the books today. Rubin expects to add roughly 90,000 more of them over its ten-year survey, and to lift that share to about 70 percent.
The rate is the part that is hard to hold in your head. In the survey's early years the observatory expects to find 11,000 asteroids every two or three nights, enough to triple the number of known asteroids and to raise the count of trans-Neptunian objects by close to a factor of ten. Rubin's own summary of what that means is that discoveries which used to take years or decades will now arrive in months. A catalogue is not a defence. It is what any defence would have to be built from, and the open question is what gets done with a sky that is finally being written down.
These are candidate discoveries rather than confirmed ones. In this batch alone the Minor Planet Center identified several hundred cases in which Rubin's tracklets may correspond to objects already on record, and those are still being analysed, so the final count of genuinely new objects will come in below 20,000. The centre also treated the submission as an end-to-end stress test and found things to fix, including a bug that stopped correctly computed orbits from being exported into the next day's public update, since corrected. And a catalogue of near-Earth objects is the first step in planetary defence, not the answer to it. The larger figures, roughly 90,000 near-Earth objects and a tripled asteroid catalogue, are projections for a ten-year survey that has barely started.
What is a candidate discovery, and why is it not a discovery yet?
Rubin links its own observations into candidate objects before sending them in, and the Minor Planet Center then checks every tracklet against the orbits of objects already known. Where there is a match, the observations are attached to the known body and no new designation is created. In the February batch the centre flagged several hundred cases that may turn out to be already known, so the confirmed total will come in below 20,000.
How does 20,000 in one night compare with what Rubin had found before?
Across about 1.6 years of observing, Rubin had found 12,700 asteroids in total: 73 in late 2024, 1,514 across April and May 2025, and roughly 11,000 over that summer. The single batch filed on 5 February 2026 held about 20,000 candidate discoveries drawn from some 246,000 observations. The observatory expects to keep finding asteroids at around 11,000 every two to three nights in the survey's early years.
What is the Minor Planet Center, and why does everything go through it?
It is the International Astronomical Union body that keeps the world's official register of asteroids and comets, designating new objects and maintaining their orbits. Because Rubin sends data that is already linked, at a volume the standard route was not built for, the centre wrote a dedicated pipeline for it and added an extra stage of manual vetting. It describes the February batch as an end-to-end stress test that the pipeline came through, while exposing a few bottlenecks to improve.
Does finding more asteroids make Earth safer?
It is the first step rather than the answer. About 40 percent of near-Earth objects larger than 140 metres are catalogued today, and Rubin expects to lift that towards 70 percent while adding roughly 90,000 more over its ten-year survey. Knowing where an object is and where it is going is what any warning or deflection would have to rest on.
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