If you're a fan of cosmic celebs Neil deGrasse Tyson or Carl Sagan, you already know that everything is made of stardust: The fusion that churns inside stars turns small elements (like hydrogen) into large ones (like carbon) that go on to build planets. Now, by tracking cosmic dust, scientists have found evidence that it may be the violent star explosions called supernovas that push these life-giving materials into the galaxy's future stars and planets.
In a study published Thursday in Science, researchers led by Cornell postdoctoral associate in astronomy Ryan Lau made the first direct observations of cosmic dust -- the smokey wisps of raw materials that cloud around stars and build new ones along with planets -- coming straight out of a supernova. Lau and his team used NASA's Stratospheric Observatory for Infrared Astronomy (SOFIA) to closely examine Supernova Remnant Sagittarius A East in infrared.
Scientists already knew that supernovas produced enough dust to seed the universe with new planets and stars, making for lively galaxies. But the explosion of a star is a violent process, and they weren't sure whether enough of the dust created by the explosion could also survive it.
They found that the 10,000-year-old cloud of interstellar dust had retained a lot of the dust created by the supernova -- about 7 to 20 percent of it -- after the hard rebound that occurs when the outward blast of a star explosion hits nearby interstellar gas and dust and turns back inward.
"Our observations reveal a particular cloud produced by a supernova explosion 10,000 years ago contains enough dust to make 7,000 Earths," Lau said in a statement. That surviving dust was free to flow back into interstellar space and provide material for new galaxies.
Lau credits the discovery to SOFIA, which sits on a modified Boeing 747SP jumbo jet.
"We were on a flying observatory traveling at 600 mph (965 km/h) at an altitude of 45,000 feet (13,715 meters) to take images of a 10,000-year-old supernova remnant located 27,000 light-years away from us at the center of our galaxy," Lau told Space.com. "No other currently operating observatory other than the Stratospheric Observatory for Infrared Astronomy could detect this dust."
Correction: A previous version of this post stated: Now, by tracking cosmic dust, scientists have found evidence that it may be the violent star explosions called supernovas that push these life-giving materials into future galaxies. It should have read "into the galaxy's future stars and planets."