The Hubble Space Telescope zoomed-in on a particularly puzzling asteroid discovered in August to reveal a stunning sight speeding through space. The asteroid has six comet-like trails of dust radiating from it like spokes on a wheel.
According to NASA, an object like this has never been seen by the Hubble before. But once it passed into the Hubble's line of sight, its peculiar presence was noticed immediately.
"We were literally dumbfounded when we saw it," said David Jewitt of the University of California at Los Angeles, who led the investigation into the strange asteroid. "Even more amazing, its tail structures change dramatically in just 13 days as it belches out dust. That also caught us by surprise. It's hard to believe we're looking at an asteroid."
Jewitt and his team have published a paper detailing their observations of the peculiar asteroid in The Astrophysical Journal of Letters.
The asteroid, which is officially designated P/2013 P5, was first spotted on Aug. 27 by astronomers using the the Pan-STARRS survey telescope in Hawaii. At the time the asteroid appeared to be unusually "fuzzy," but when the Hubble zoomed in on it a few weeks later, it revealed that all the fuzz was caused by the comet-like streams of dust flying off the asteroid.
After two more weeks, the asteroid's appearance has completely changed. The scientists said it looked like the whole structure had swung around, prompting them to call the asteroid a "weird and freakish" object. "We were completely knocked out," Jewitt said. The tails of rotating dust beaming off the asteroid give it the appearance of a rotating lawn sprinkler, the scientists said.
One possible explanation for the asteroid's odd behavior and appearance is that radiation pressure increased the asteroid's spin rate so much that the asteroid's weak gravity could no longer hold it together.
"If that happened, dust could slide toward the asteroid's equator, shatter and fall off, and drift into space to make a tail," the Hubble News Center said in a statement. "So far, only about 100 to 1,000 tons of dust, a small fraction of the P/2013 P5's main mass, has been lost. The asteroids nucleus, which measures 1,400 feet wide, is thousands of times more massive than the observed amount of ejected dust."
Jewitt suspects this never-before-seen asteroid type will become more common upon future observations.
"In astronomy, where you find one, you eventually find a whole bunch more," Jewitt said. "This is just an amazing object to us, and almost certainly the first of many more to come."