An agreement between NASA and the US Space Force recently authorized the public release of data collected over decades by US government sensors on fireballs (large, bright meteors, also known as fireballs) for the benefit of the scientific and planetary defense communities. This action is a collaboration between NASA’s Planetary Defense Coordination Office (PDCO) and the US Space Force to continue our nation’s planetary defense efforts, which include the search, tracking, characterization, and cataloging of Near-Earth Objects (NEOs). The newly released data consists of information about how fireballs change in brightness as they pass through the Earth’s atmosphere, called light curves, which could improve the planetary defense community’s current ability to model the impacts of larger asteroid impacts that could one day pose a threat. to the ground.
Fireballs, very bright meteors that can be seen even in daylight, are a regular occurrence – on the order of a few dozen times a year – as a result of asteroids that are too small to reach the earth but large enough to explode on impact with our planet. with the earth’s atmosphere. US government sensors detect these atmospheric impact events, and fireball data is fed into the NASA Jet Propulsion Laboratory’s Center for the Study of Near-Earth Objects (CNEOS) fireball database, which contains data dating back to 1988 for nearly a thousand fireball events. Now, planetary defense experts will have access to even more detailed data, in particular, to information about the light curve, which captures the change in optical intensity within a few seconds after the decay of an object in the atmosphere. This uniquely rich dataset is in high demand by the scientific community as the destruction of an object in the Earth’s atmosphere provides a scientific insight into the strength and composition of an object based on the altitude at which it decays and disintegrates. The approximate total radiated energy and pre-re-entry velocity vector (i.e. direction) can also be better derived from fireball light curve data.
“The growing archive of fireball reports hosted on NASA’s CNEOS Fireballs website has greatly expanded scientific knowledge and contributes to the White House-approved National Near-Earth Object Preparedness Strategy and Action Plan,” said Lindley Johnson, planetary mission officer. protection at NASA headquarters. . “The release of these new fireball data demonstrates another key area of collaboration between NASA and the US Space Force and helps further the quest to improve our ability to understand these objects and our preparedness to respond to NEO impact hazards.”
Recently, a small asteroid about 2 meters in size, so small that it did not pose a threat to the Earth, was discovered in space as it approached the Earth and crashed into the atmosphere southwest of Jan Mayen, a Norwegian island located almost 300 miles ( 470 km) from the east coast. Greenland and northeast of Iceland. Although this asteroid, designated 2022 EB5, was much smaller than the objects NASA was supposed to detect and warn of, CNEOS continued to update NASA’s PDCO with impact site predictions as observations leading up to the 2022 EB5 impact were collected, offering the planetary protection community a real – A simple scenario to test NEO tracking capabilities and confirm that the impact prediction process and models are adequate to provide timely and accurate notification of a potential impact with a larger object if it is detected on an Earth path. Like other fireball events, the 2022 EB5 impact was detected by US government sensors and reported by the US Space Force, confirming the time and location predicted by CNEOS, and has been added to NASA’s JPL CNEOS archive of these events.