A new report says 2020 was a record year for discovering new asteroids, particularly those with near-Earth orbits in spite of the COVID-19 pandemic shutting down a number of observatories.
The report, published Thursday in the science journal Nature, says astronomers registered 2,958 previously unknown near-Earth asteroids over the course of the year, the most since 1998, the year the U.S. space agency, NASA, began tracking such objects.
More than half of the asteroids and other objects recorded came from the Catalina Sky Survey in Arizona, which uses its three telescopes to hunt for potentially threatening space rocks. Astronomers there discovered 1,548 near-Earth objects, even with the center closed briefly last spring because of the pandemic, and a longer closure in June, due to a wildfire in the area.
Among the Catalina 2020 discoveries was a rare “minimoon” named 2020 CD3, a tiny asteroid less than 3 meters in diameter that had been temporarily captured by Earth’s gravity. The minimoon broke away from Earth’s pull last April.
The report says another 1,152 discoveries came from the Pan-STARRS survey telescopes in Hawaii. One of the objects discovered there was not a space rock at all, but a leftover rocket booster that had been looping around in space since 1966 when it helped to launch a NASA spacecraft to the Moon.
The report says at least 107 of the objects discovered last year came closer to Earth than the distance between the planet and the Moon.
Among last year’s near-misses was the tiny asteroid 2020 QG, which skimmed just 2,950 kilometers above the Indian Ocean in August. That was the closest known approach by an outer space object, until just three months later when another small object, named 2020 VT4, passed less than 400 kilometers (about the length of New York State) from the planet.
Observers did not discover 2020 VTA until 15 hours after it had flown by the earth. The scientist say had it hit, it would probably have broken apart in Earth’s atmosphere.
NASA created the Center for Near Earth Objects (CNEO) in 1998, fulfilling a Congressional request to track and catalogue at least 90% of space objects a kilometer or larger that may come near Earth and/or cause a threat. Since then, CNEO and its contributing astronomers have logged more than 25,000 such objects.