Exploding supernova, dust producer in galaxies
Washington: The European Space Agency''s Herschel Space Observatory has detected cosmic dust in supernova 1987A, which exploded 24 years ago in the Large Magellanic Cloud, a small galaxy near to the Milky Way — a finding that may help solve a mystery of the early Universe.
The data has revealed that the exploding stars could be a major dust producer in those early galaxies.
The discovery could explain the source of the huge amount of dust that mixes with gas to form raw material for new stars, planets and, ultimately, life.
Herschel’s images are the first clear-cut far-infrared observations of
SN1987A. They reveal cold dust grains at about -250 degrees Celsius, emitting more than 200 times the Sun’s energy.
“The supernova remnant was much brighter at infrared wavelengths than we were expecting,” said lead author Mikako Matsuura, University College London.
The remnant’s brightness was used to estimate the amount of dust.
Surprisingly, there turned out to be about a thousand times more dust than astronomers had thought a supernova was capable of producing -- enough to make 200,000 planets the size of Earth.
The many old red giant stars in today’s universe are thought to be the major dust producers, with the grains condensing like soot in a chimney as warm gases flow away from the star.
“These observations provide the first direct evidence that supernovas can produce the dust seen in young galaxies at great distance,” said Goran Pilbratt, ESA’s Herschel project scientist.
“It is a significant result and shows yet again the value of opening a unique window onto the Universe,” he added.
The findings appear in the journal Science.