Researchers have followed star dust formation in real time and have used the data to explain how small cosmic particles survive violent environment of the Universe.
Star dust is important for the formation of stars, terrestrial planets. Scientists believe that supernova explosions might be the source of this dust. Supernova is an explosion of a giant star and can release massive amount of energy. Few problems with the idea of supernovae giving rise to dust were that nobody could explain how small particles of cosmic dust could survive the supernova shockwaves.
In the present study, a team of astronomers used European Southern Observatory's Very Large Telescope in northern Chile to analyze light from supernova SN2010jl.
According to the researchers, cosmic dust production occurs in two stages: the first one begins immediately after the explosion and the second one after several hundreds of days.
For the study, researchers observed the supernova SN2010jl nine times in the months after explosion and for a tenth time two and half years later. SN2010jl was observed using both visible and near-infrared wavelengths. The supernova was a result of death of a massive star in a small galaxy of UGC 5189A
"By combining the data from the nine early sets of observations we were able to make the first direct measurements of how the dust around a supernova absorbs the different colours of light," said lead author Christa Gall from Aarhus University, Denmark, according to a news release. "This allowed us to find out more about the dust than had been possible before."
A major find of the research was that the cosmic dust particles were large, about 1 to 4.2 micrometers across. The size of the dust might seem small by earth standards, however, are four times larger than typical width of dust particles in the Milky Way.
"Our detection of large grains soon after the supernova explosion means that there must be a fast and efficient way to create them," said co-author Jens Hjorth from the Niels Bohr Institute of the University of Copenhagen, Denmark, and continued: "We really don't know exactly how this happens."
According to the researchers, supernova's shockwave creates a cool, dense shell of gas around the star. This shell provides the right environment for the dust to form and grow.
In the second stage, dust formation is accelerated. Researchers said that if the dust production trend in the SN2010jl continues, then by 25 years, the total mass of dust will be about half the mass of the Sun.
The study results are published in the journal Nature.