A pair of astronomers have found and categorised half a million new asteroids lurking in old data. Figuring out exactly where these objects came from could be crucial to understanding the early solar system.
Alexey Sergeyev and Benoit Carry of the Côte d’Azur University in France found the objects by combing images from the Sloan Digital Sky Survey (SDSS). This research, which uses a telescope at the Apache Point Observatory in New Mexico, took images of a large swath of sky from 1998 to 2009. It also measured the colors of the objects it saw.
The research monitors hundreds of thousands of small bodies in our solar system. The message gives the object’s coordinates at the time of its discovery so other astronomers can track it. And they’ll want to know that is any asteroid or comet that will come within about 30 million miles of Earth’s orbit. The asteroid may blew up with the energy of the largest hydrogen bombs ever detonated on Earth, vaporizing the desert and unleashing deadly supersonic winds for many miles.
Sergeyev and Carry examined the images for fast-moving objects, which could be asteroids or comets. They found over 1 million observations of objects we already knew about, along with 506,200 observations of objects unrelated to anything we’ve seen before, most of them asteroids.
Continuous observations with other telescopes will allow researchers to find millions more asteroids, he says. In the meantime, these will have to be monitored to discover their trajectories, in order to determine if they are really new or if they have been observed before, and to find out if any of them could be dangerous for the Earth.
The number of asteroids that have not yet been cataloged was surprising, says Carry. “We were expecting about 30,000 or 40,000 more asteroids and all of a sudden we had this catalog of monsters,” he says. “It was supposed to be a couple of weeks’ work, and it turned out to be a year.”