NASA repurposed Kepler space telescope, now K2 mission, have proved a theory that white dwarfs are capable to destroy planets within its solar system. The telescope received data about a rocky object being torn apart as it spirals around a white dwarf star, Joinfo.ua reports with the reference to NASA.
“We are for the first time witnessing a miniature “planet” ripped apart by intense gravity, being vaporized by starlight and raining rocky material onto its star,” said Andrew Vanderburg, graduate student from the Harvard-Smithsonian Center for Astrophysics in Cambridge, Massachusetts, and lead author of the paper published in Nature.
As stars like our sun age, they puff up into red giants and then gradually lose about half their mass, shrinking down to 1/100th of their original size to roughly the size of Earth. This dead, dense star remnant is called a white dwarf.
The devastated planetesimal, or cosmic object formed from dust, rock, and other materials, is estimated to be the size of a large asteroid, and is the first planetary object to be confirmed transiting a white dwarf. It orbits its white dwarf, WD 1145+017, once every 4.5 hours. This orbital period places it extremely close to the white dwarf and its searing heat and shearing gravitational force.
Observing the universe K2 watched a 40% dip of brightness of the white dwarf, occurring every 4.5 hours. It meant that a small object periodically blocks the light from the dwarf. The white dwarfs have an intense gravity, so their surface is expected to have only light elements of helium and hydrogen. For years, researchers have found evidence that some white dwarf atmospheres are polluted with traces of heavier elements such as calcium, silicon, magnesium and iron. Scientists have long suspected that the source of this pollution was an asteroid or a small planet being torn apart by the white dwarf’s intense gravity.
“For the last decade we’ve suspected that white dwarf stars were feeding on the remains of rocky objects, and this result may be the smoking gun we’re looking for,” said Fergal Mullally, staff scientist of K2 at SETI and NASA’s Ames Research Center in Moffett Field, California. “However, there’s still a lot more work to be done figuring out the history of this system.”