THOR Might Save Us All One Day

Ed Lu is a former NASA astronaut with a PhD in applied physics, and he is worried about near-Earth asteroids—space rocks at least 460 feet in diameter that have been nudged by gravity into Earth’s neighborhood. According to the New York Times, only 40% of the estimated 25,000 near-Earth asteroids have been located. The rest are flying around undetected; however, their locations might be "hiding in plain sight" within existing data. This week, Lu’s nonprofit B612 Foundation—established in 2002 to assist in planetary defense—announced the discovery of 104 previously unknown asteroids. They’re not near Earth, but their existence validates a new approach to space exploration.

Unlike previous asteroid discoveries, researchers with B612’s Asteroid Institute did not use a telescope of their own. Instead, astronomers at the University of Washington developed a novel algorithm called Tracklet-less Heliocentric Orbit Recovery (THOR), which can comb through existing digital archives and identify potential asteroids that went unnoticed by astronomers who were focused on finding other things, like supernovas and exoplanets. Essentially, THOR can turn any telescope into an asteroid hunter, but the work requires enormous computational power that’s only possible thanks to cloud computing. Google contributed to the project by providing time on Google Cloud, per the Times.

According to UW News, the 104 asteroids were found within “a small initial subset” of the nearly 68 billion observations archived by the National Optical-Infrared Astronomy Research Lab in Tucson. The Minor Planet Center confirmed the existence of some of the newly discovered asteroids, thereby validating THOR’s potential. Astronomers expect to make thousands of additional discoveries in NOIRLab archives and other data sets they plan to examine. Per NBC, Lu said that “discovering and tracking asteroids is crucial to understanding our solar system, enabling development of space, and protecting our planet from asteroid impacts.” As to what anyone can do if a planet killer is discovered, the Times says NASA is planning the Double Asteroid Redirection Test mission for later this year, and China has a similar program in the works. (More near earth objects stories.)