Post by The Ultimate Nullifier on Jan 5, 2014 16:19:55 GMT -6
This asteroid looks just like a lawn sprinkler!
Officially known as P/2013 P5, it has six comet-like tails of dust radiating from it like spokes on a wheel--the first asteroid like it we have ever seen.
And the thanks for that goes to the inveterate Hubble Space Telescope.
Unlike all other known asteroids, which appear simply as tiny points of light, this asteroid resembles a rotating lawn sprinkler. Astronomers are puzzled over the asteroid's unusual appearance.
"We were literally dumbfounded when we saw it," said lead investigator David Jewitt of the University of California at Los Angeles. "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."
Astronomers believe it is possible the asteroid's rotation rate increased to the point where its surface started flying apart, causing it to periodically eject dust. They do not believe the tails are the result of an impact with another asteroid because they have not seen a large quantity of dust blasted into space all at once.
After astronomers spotted the asteroid on August 27, 2013, Hubble was dispatched to take a photo. What is most remarkable is how different the asteroid looked when Hubble photographed it on September 10, 2013 and again on September 23, 2013. It was as if the entire structure had swung around in that two-week period.
"We were completely knocked out," Jewitt said.
Jewitt has theorized that rotational breakup must be a common phenomenon in the asteroid belt; it may even be the main way small asteroids die.
"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."
Jewitt said it appears P/2013 P5 is a fragment of a larger asteroid that broke apart in a collision roughly 200 million years ago. There are many collision fragments in orbits similar to that of P/2013 P5. Meteorites from these bodies show evidence of having been heated to as much as 1,500 degrees Fahrenheit. This means the asteroid likely is composed of metamorphic rocks and does not hold any ice as a comet does.
The study findings were published in The Astrophysical Journal Letters.