HelioLinc3D Algorithm Discovers its First “Potentially Hazardous” Near-Earth Asteroid

The Vera C. Rubin Observatory’s innovative asteroid detection algorithm, HelioLinc3D, has successfully spotted its inaugural “potentially hazardous” asteroid named 2022 SF289. This event represents a significant progression in the detection of near-Earth asteroids and a critical milestone in data-driven astronomy.

HelioLinc3D, a cutting-edge asteroid discovery algorithm, was created for the Observatory’s impending sky survey. It recently discovered its maiden “potentially hazardous” asteroid, tagged 2022 SF289.

This algorithm was specifically created to find near-Earth asteroids as part of the Vera C. Rubin Observatory’s planned decade-long night sky survey. The algorithm discovered its first “potentially hazardous” asteroid, a term used for space rocks close to Earth that warrant constant monitoring by scientists. The asteroid, approximately 600-foot-long and named 2022 SF289, was detected during a test run of the algorithm using the ATLAS survey in Hawaii. The discovery of 2022 SF289, which poses no immediate threat to Earth, attests to the proficiency of the next-gen HelioLinc3D algorithm in identifying near-Earth asteroids using fewer and more scattered observations than current methods.

The algorithm also detected its first “potentially hazardous” asteroid (PHA) for the Vera C. Rubin Observatory’s forthcoming Legacy Survey of Space and Time. PHAs are celestial bodies with the potential to come dangerously close to Earth.

The discovery of 2022 SF289 affirms the software’s practical effectiveness that Rubin will employ to search for numerous unknown PHAs, thus enhancing our safety, says Rubin scientist Ari Heinze, the main developer of HelioLinc3D and a researcher at the University of Washington.

The solar system is filled with tens of millions of rocky bodies, ranging from small asteroids to dwarf planets as big as our moon. These objects are remnants from over four billion years ago when our solar system’s planets formed and settled into their current positions.

Most of these bodies are distant, but some have orbits close to Earth, termed near-Earth objects or NEOs. The closest ones that follow a trajectory bringing them within about 5 million miles of Earth’s orbit demand special attention. These “potentially hazardous asteroids” (PHAs) are regularly searched and tracked to ensure they won’t collide with Earth, an event with potentially disastrous consequences.

PHAs are searched for using specialized telescope systems like the NASA-funded ATLAS survey, managed by a team at the University of Hawaii’s Institute for Astronomy. Scientists make discoveries by observing a point of light moving unmistakably in a straight line over a series of images. This method has led to the discovery of approximately 2,350 PHAs, but scientists estimate an equal number are yet to be discovered.

The Vera C. Rubin Observatory, located in the Chilean Andes, is preparing to join the hunt for these objects in early 2025. Rubin’s observations, funded mainly by the U.S. National Science Foundation and the U.S. Department of Energy, will significantly speed up the discovery rate of PHAs. Rubin’s novel observing “cadence” necessitates a new discovery algorithm to reliably spot space rocks.

Rubin’s solar system software team at the University of Washington’s DiRAC Institute is developing such codes. Together with Smithsonian senior astrophysicist and Harvard University lecturer Matthew Holman, and Siegfried Eggl, a former University of Washington researcher now at the University of Illinois at Urbana-Champaign, Heinze developed HelioLinc3D to identify asteroids in Rubin’s data. As Rubin is still under construction, Heinze and Eggl tested HelioLinc3D on existing data to see if it could discover a new asteroid.

ATLAS astronomers John Tonry and Larry Denneau provided their data for a test. The Rubin team used HelioLinc3D to search through this data, and on July 18, 2023, it discovered its first PHA: 2022 SF289. The asteroid had been initially imaged by ATLAS on September 19, 2022, at a distance of 13 million miles from Earth.

In hindsight, ATLAS had observed 2022 SF289 thrice on four separate nights, but never four times in one night, the current requirement to be identified as a new NEO. Here, HelioLinc3D was successful: it combined fragments of data from all four nights and made the discovery.

2022 SF289, classified as an Apollo-type NEO, comes within 140,000 miles of Earth’s orbit, closer than the moon. Despite being classified as “potentially hazardous” due to its 600ft diameter, it poses no threat of collision with Earth for the foreseeable future. Its discovery has been announced in the International Astronomical Union’s Minor Planet Electronic Circular MPEC 2023-O26.

Rubin scientist Mario Jurić, director of the DiRAC Institute, anticipates that once the Rubin Observatory is operational, the HelioLinc3D will discover an object like this every night. This is a preview of the coming era of data-driven astronomy, where advancement in algorithms is as crucial as the new, large telescopes.

The Rubin Observatory receives financial support from the U.S. National Science Foundation, the U.S. Department of Energy, and private funding raised by the LSST Corporation.

Frequently Asked Questions (FAQs) about HelioLinc3D

More about HelioLinc3D

• Vera C. Rubin Observatory
• ATLAS Survey
• Zwicky Transient Facility Survey
• B612 Asteroid Institute’s ADAM platform
• International Astronomical Union’s Minor Planet Electronic Circular MPEC 2023-O26
  (Note: This is a general link to MPEC, as I couldn’t provide a direct link to the specific MPEC 2023-O26)
• University of Washington’s DiRAC Institute