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COURTESY ROB RATKOWSKI / HARVARD-SMITHSONIAN
Haleakala's Pan-STARRS PS1 telescope puts on a display of its power, finding 19 near-Earth asteroids in a single night.
Scientists at the Pan-STARRS PS1 telescope on Haleakala, Maui, caused a stir among their fellow astronomers when they discovered 19 near-Earth asteroids on the night of Jan. 29, the most asteroids ever discovered in a single night.
According to Nick Kaiser, head of the Pan-STARRS project, the impressive display of the year-old telescope’s capabilities was made possible by recent software improvements and refinements in observational techniques.
While the project receives funding from NASA and the U.S. Air Force Research Laboratory for its asteroid-detecting activities, it is also involved in other studies.
"We’re not funded exclusively for this, but we thought we’d do it as a demonstration," Kaiser said. "We hope to generate more funding for (asteroid detection). Ideally, we would be able to build three more telescopes for better observation."
In the past, the telescope had generated false detections that made it difficult to discern real and phantom asteroids. During the Jan. 29 demonstration, the astronomers took four exposures — "one after the other" — to ensure accurate observation, Kaiser said.
In particular, the scientists were looking for asteroids "larger than a few hundred meters" whose orbits could potentially put them on a collision course with Earth. Kaiser said there are about 1,000 asteroids larger than a kilometer and tens of thousands of smaller objects. He said the telescope is capable of detecting as many as 50 of these objects per month.
On the night of the observation, Pan-STARRS software engineer Larry Denneau processed and transmitted PS1 data from his office at the University of Hawaii at Manoa. New discoveries were forwarded to the Minor Planet Center in Cambridge, Mass., where the information was made available so other astronomers could re-observe the objects.
As astronomer Richard Wainscoat noted, mainland observatories usually help to confirm discoveries, but widespread snowstorms that weekend forced Pan-STARRS astronomers to confirm many of their own discoveries. Over the next three days, that duty fell to Wainscoat, fellow astronomer David Tholen and graduate student Marco Micheli.
While the likelihood of near-Earth asteroids actually colliding with Earth is remote — roughly a 1-in-1,000 chance, according to Kaiser — being able to accurately account for their whereabouts will allow governments to act should the unlikely actually develop into a real threat.
"It’s like the risk developing a rare disease," Kaiser said. "The chance that it will actually happen is small, but the risk, whatever it is, is real. You want to find out if it will happen."
