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The Jet Propulsion Laboratory (JPL) of the U.S. space agency, NASA, says it has new software that will allow its Center for Near Earth Object Studies (CNEOS) to better assess potential threats posed by asteroids that can come close to Earth.
In a press release on Monday, NASA astronomers said they have upgraded their impact software, called Sentry, with its next generation, Sentry-II, to better evaluate near-Earth asteroid (NEA) impact probabilities.
NASA said to date, almost 28,000 NEAs have been found by survey telescopes that continuously scan the sky, making about 3,000 new discoveries per year. But with better technology and newer, bigger telescopes scheduled to come online, that number is expected to multiply quickly, necessitating the software upgrade.
Contrary to what some might believe, asteroids are extremely predictable celestial bodies that obey the laws of physics and follow knowable orbital paths around the sun, NASA scientists say. Sometimes, when those paths bring those objects closer to Earth's future position in space, uncertainties in the asteroids' path raise the possibility of a collision with Earth.
Navigation engineer Javier Roa Vicens, who had led the development of Sentry-II while working at JPL and recently moved to SpaceX, said the first generation of Sentry was "very capable." He said that in less than an hour, it could produce the impact probability for a newly discovered asteroid for the next 100 years, what he called "an incredible feat."
But JPL scientists say the Sentry-II software can rapidly calculate impact probabilities for all known NEAs, including some special cases not captured by the original Sentry. For example, its calculations consider how the sun's heat and Earth's own gravity affect the trajectory of asteroids.
The scientists say that by systematically calculating impact probabilities in this new way, the impact monitoring system is more robust, enabling NASA to confidently assess all potential impacts with odds as low as a few chances in 10 million.
Since 2002, the JPL-managed CNEOS, at its headquarters in Southern California, has calculated every known NEA orbit to improve impact hazard assessments in support of NASA's Planetary Defense Coordination Office.