An agreement between NASA and the US Space Force recently authorized the release of decades of data collected by US government sensors on fireball events (large, bright meteors also called bolides) for the benefit of the scientific communities and the public. planetary defense. This action is the result of collaboration between NASA’s Planetary Defense Coordination Office (PDCO) and the U.S. Space Force to continue our nation’s planetary defense efforts, which include research, tracking, characterization and cataloging near-Earth objects (NEO). The newly released data is comprised of information on how the brightness of bolides changes as they pass through the Earth’s atmosphere, called lightcurves, which could improve the planetary defense community’s current ability to model the effects of larger asteroid impacts that could one day pose a threat. towards the earth.
Bolides, very bright meteors that can even be seen in daylight, occur regularly – on the order of several dozen times a year – when our planet is impacted by asteroids too small to reach the ground but large enough large to explode on impact. with the earth’s atmosphere. US government sensors detect these atmospheric impact events, and bolide data is reported to the fireball database at the Center for Near-Earth Object Studies (CNEOS) at the Jet Propulsion Laboratory of the United States. NASA, 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 – specifically, light-curve information that captures the variation in optical intensity during the few seconds an object breaks through the atmosphere. . This uniquely rich dataset has been much sought after by the scientific community, as the breakup of an object in Earth’s atmosphere provides scientific insight into the strength and composition of the object as a function of the altitudes at which it breaks and disintegrates. The approximate total radiated energy and pre-entry velocity vector (i.e. direction) can also be better derived from bolide light curve data.
“The growing archive of fireball reports, as published on the NASA CNEOS Fireballs website, has significantly increased scientific knowledge and contributes to the White House-approved National Near-Earth Object Preparedness Strategy and Action Plan,” said Lindley Johnson, planetary defense officer at NASA Headquarters. . “The release of this new bolide data demonstrates another key area of collaboration between NASA and the US Space Force and helps to continue the search for improved capabilities to understand these objects and our preparedness to respond to the impact hazard that near-Earth objects land on Earth.”
Recently, a small asteroid about 2 meters in size, so small that it posed no danger to Earth, was detected in space as it approached Earth and impacted the atmosphere at southwest of Jan Mayen, a Norwegian island nearly 300 miles (470 kilometers) off the east coast. Greenland and northeast Iceland. While this asteroid, designated 2022 EB5, was much smaller than the objects NASA is tasked with detecting and warning about, CNEOS continued to update NASA’s PDCO with impact location predictions as and as observations were collected prior to the impact of 2022 EB5, providing the planetary defense community with a real-word scenario to test NEO tracking capabilities and provide assurance that the process and models Impact prediction sensors are adequate for quick and accurate notification of the potential impact of a larger object, should an object be discovered on a trajectory towards Earth. Like other bolide events, the impact of 2022 EB5 was detected by US government sensors and reported by US Space Force units, confirming the time and place predicted by CNEOS, and added to the archives of NASA on these events at JPL CNEOS.