Astronomers using NASA’s Stratospheric Observatory for Infrared Astronomy (SOFIA), the world’s largest airborne astronomical observatory, have made direct observations of cosmic building-block dust resulting from a supernova remnant called Sagittarius A East.
This is a composite, false-color image of the supernova remnant Sagittarius A East. Image credit: R. M. Lau et al.
One of astronomy’s big questions is why galaxies – forming as recently as 1 billion years after the Big Bang – contain so much dust. The leading theory is that supernovae contain large amounts of metal-enriched material that, in turn, harbors key ingredients of dust, like silicon, iron and carbon.
“Dust itself is very important because it’s the stuff that forms stars and planets, like the Sun and Earth, respectively, so to know where it comes from is an important question,” said team member Dr Ryan Lau of Cornell University, Ithaca, NY.
“Our work strongly reinforces the theory that supernovae are producing the dust seen in galaxies of the early Universe.”
Dr Lau and his colleagues examined Sagittarius A East, a 10,000-year-old remnant of a core-collapse supernova located 26,000 light-years away near the center of our Milky Way Galaxy.
“When a supernova explodes, the materials in its center expand and form dust,” Dr Lau said.
“This has been observed in several young supernova remnants – such as the famed SN 1987A and Cassiopeia A. In the turbulent supernova environment, scientists expect the churning dust to be destroyed.”
“That is theoretically, there have been no direct observations of any dust surviving the environment of the supernova remnant, until now, and that’s why our observations of an old supernova are so important,” Dr Lau said.
The results were published online March 19 in the journal Science.
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R. M. Lau et al. Old supernova dust factory revealed at the Galactic center. Science, published online March 19, 2015; doi: 10.1126/science.aaa2208
