Explosions are probably primary source of dust in galaxies
Chandra/Royal Military College of Canada, STScI, CXC, NASA
Supernova 2010jl is helping unravel the origin of interstellar dust, the sootlike grains that fill the space between stars. New observations published July 9 in Nature show a shell of dust forming around the dying star within weeks of the explosion. The data support the idea that supernovas are the main dust factories in the universe.
The unusually bright supernova, first seen in 2010, is roughly 160 million light-years away in the constellation Leo. Researchers watched the dust form almost in real time for nearly two and a half years using the Very Large Telescope in Chile. They did so by tracking how much the dust dimmed different colors of light from the explosion.
The dust probably formed in the wake of the supernova’s shock wave, which traveled at nearly 126 million kilometers per hour as it tore through clouds of gas that had previously been shed by the dying star. The dust grains are larger than expected, some bigger than a micrometer, which should help them survive the harsh environment of interstellar space, says lead author Christa Gall, of Aarhus University in Denmark. Their hardiness helps explain how supernovas might contribute much of the dust amid galaxies, she adds.
C. Gall et al. Rapid formation of large dust grains in the luminous supernova 2010jl. Nature. Posted online July 9, 2014. doi: 10.1038/nature13558.
N. Smith et al. A massive progenitor of the luminous Type IIn supernova 2010jl. Astrophysical Journal. Vol. 732, May 10, 2011, p. 63. doi: 10.1088/0004-637X/732/2/63