Technology’s ability to solve global problems is often overhyped. But when it comes to saving the world from asteroid strikes, lines of code may prove to be our savior.
Telescopes that scan the sky for stray space rocks are manned by astronomers, but their systematic motions are driven by ones and zeroes. With so many overcast skies to read, scientists rely on algorithms to spot suspicious, fast-moving objects, including asteroids that could threaten Earth.
Standard algorithms require four images, taken in one night, of a moving object to confirm whether it is a real space rock. But new software developed by researchers at the University of Washington cuts the number of required nightly observations in half, boosting observatories’ ability to quickly identify these lithic projectiles. And the program, named HelioLinc3D, has already found a near-Earth asteroid that older surveys missed.
Analysis of data from NASA-funded ATLAS (Asteroid Terrestrial-impact Last Alert System) survey, the program found an asteroid that ATLAS and similar surveys missed — a 600-foot-long one, the kind that could destroy a large city.
Named 2022 SF289, the asteroid is classified as “potentially dangerous,” based on its size and proximity. But although this asteroid closest approach is within 140,000 miles of Earth’s orbit, half the distance to the moon, there is no risk of impact for the next century and likely for many millennia to come.
HelioLinc3D will not only augment the efforts of pre-existing asteroid surveys. It was designed specifically for the Vera C. Rubin Observatory in Chile. The observatory’s large mirror, massive camera and wide eye can see almost everything in the night sky in unprecedented detail, from distant collapsed stars in fuzzy-looking asteroids swimming in our galactic backwater.
Hoping to catalog as many objects as possible, the Rubin telescope is designed to quickly sweep the sky each night. Without HelioLinc3D, the observatory would not be able to show the asteroid-filled area around our planet. “The discovery of 2022 SF289 is the proof,” Ari Heinzethe principal developer of HelioLinc3D and a researcher at the University of Washington, said.
The world’s family of asteroid-hunting telescopic surveys have been found so far more than 32,000 near-Earth asteroids. Most of those capable of causing major planetary destruction were found because it was easier to see larger rocks that glowed in the sunlight.
But asteroids that are at least 460 feet long — those that have the potential to wipe out cities or small countries, should they ever hit Earth — are weaker and harder to find. Most of these are currently undiscovered, with about 10,500 found out of a projected total of around 25,000.
The four images a night required by conventional survey algorithms to detect asteroids are not always possible due to bad weather conditions, the extreme faintness of an object, or the brightness of a brighter star or galaxy. So an asteroid can be captured in multiple survey images over multiple nights and still remain unidentified – not ideal for planetary defense.
The Rubin Observatory, which is scheduled to begin its 10-year survey of the sky in 2025, will be able to spot obscure objects, including potentially city-killing asteroids. And with HelioLinc3D, the observatory only needs two images per night, on three different non-consecutive nights, to confirm the presence of an asteroid.
“It took us almost 200 years to leave a well-known asteroid in a million. Depending on when we start, it will take us between three and six months to double that,” Mario Jurican astronomer at the University of Washington and team leader of the HelioLinc3D project, said.
Rubin’s next-generation instruments will catalog not only asteroids but “everything that moves,” including comets, icy worlds beyond Neptune and interstellar entities, said Meg Schwamban astronomer at Queen’s University Belfast who was not involved in the work.
He added that the Rubin Observatory will be the engine that makes the discovery, and HelioLinc3D is “the engine. It will rewrite the solar system. The hope is to discover inside the dark and empty sea with so many islands – all the fascinating remains of the fascinating creation of the solar system.