More asteroids than we believed? Aerospace professor weighs in on discovery

A detection tool designed to search for potentially deadly space rocks revealed more than 100 previously unknown asteroids, according to a report released by the Asteroid Institute. Using an open-source, cloud-based system, an algorithm links points of light consistent with orbits of asteroids from reams of archival night sky images.

Masatoshi Hirabayashi, assistant professor in the Department of Aerospace Engineering in Auburn University’s Samuel Ginn College of Engineering and investigator for NASA’s Double Asteroid Redirection Test, or DART, explained the tool’s revelation and its impact.

Hirabayashi is director of Auburn’s Space Technology Application Research, or STAR, Lab and serves among a team of investigators for NASA’s DART that will measure the mission’s successes/failures once complete. His most cited research includes a variety of papers on asteroids Ryugu and Bennu, and recently authored the book, “Hayabusa2 Asteroid Sample Return Mission: Technological Innovation and Advances.”

Are there asteroids of particular concern for Earth? What are they, and when will they be close to Earth?

Not necessarily. Communities now consider small bodies larger than 50 meters to be the most critical targets for planetary defense. However, currently cataloged asteroids are far fewer than expected, particularly for those smaller than 100 meters in diameter. This is an urgent question to be resolved, defined by a decadal survey for planetary science and astrobiology, led by the National Academies, which will be the guideline of key science issues for the next decade.

Why could this discovery be a cause for concern?

​The new algorithm developed is innovative and takes advantage of existing extensive computational power to search for undiscovered asteroids that would potentially threaten the Earth. Unlike a classical approach that would require human processes, it can find candidates of undiscovered asteroids from a tremendous amount of data, which humans are never able to cover. 

Should this new tool also instead be viewed as an added protective device against potentially dangerous celestial objects?

​Certainly, yes. Cataloging potential hazardous objects is a fundamental process to monitor them and predict when and from where they approach the Earth. 

What are some of the more important things can we learn about our solar system by tracking asteroids?

​Asteroids have different faces like humans. Such differences are clues to see the history of the solar system, like we do find human histories on the Earth. Recent discoveries about carbon-rich asteroids from asteroid sample return missions OSIRIS-REx and Hayabusa2 revealed that asteroids may have been stirred more frequently than previously thought. For example, potential connections between comets and asteroids are now key science issues to be resolved. Thus, tracking various types of asteroids will enable new breakthroughs for the origin and evolution processes of the solar system. 

What is the status of the DART mission and what are its primary objectives?

The ​DART spacecraft is healthy and on the way to its target binary asteroid Didymos. The spacecraft is planned to smash into the small component of the system on Sept. 26. As part of the Auburn Family, we are thrilled to be part of this mission and dig into development of cutting-edge technologies for planetary defense.

Do you have suggestions that could help scientists do an even better job of locating asteroids?

​The algorithm developed is not the final solution to find all undocumented hazardous asteroids. Smaller asteroids are faint and always difficult to be discovered. To locate these small bodies, we need higher telescopic capabilities of detecting such faint objects.