Finding the trajectory and orbit of meteors like the one that rocked Chelyabinsk, Russia, in February could help scientists predict other impacts, and weather satellites could help.
When a huge meteor blazed across the sky over the Russian city of Chelyabinsk in February, dashboard cameras in Russians' cars weren't the only eyes on the sky recording the event.
Weather satellites operated by the US as well as countries in Europe and Asia also captured the meteor's fall, and astronomers have now gone back to cull those data, tracing a debris trail in enough detail to allow them to reconstruct the object's trajectory and orbit, according to a new study.
In case of the Chelyabinsk event, scientists had already worked out the meteor's trajectory and calculated an orbit using videos from Russia dashboard cams. But their success in now replicating that feat with satellite data represents a promising new tool. After all, not every meteor will streak through the sky in a region filled with dash cam, and this new method could help scientists predict potentially damaging meteor strikes in the future.
It's important to establish an object's orbit, because astronomers can look along that orbital path to see if the first object to arrive has others coming in behind it – and, if so, what sort of risk they present. This is especially true when the meteor arrives without warning, as the Chelyabinsk meteor did, researchers say.
The vast majority of Chelyabinsk-scale objects, which can inflict significant damage, remain undiscovered, notes Donald Yeomans, a researcher at NASA's Jet Propulsion Laboratory in Pasadena, Calif., who manages NASA's Near-Earth Object Program Office.
In principle, weather satellites could help fill big geographic gaps in the ability to directly observe impactors, says Steven Miller, deputy director of the Cooperative Institute for Research in the Atmosphere at Colorado State University in Fort Collins, who led the team that conducted the study..