Researchers using NASA’s James Webb Space Telescope have made significant progress in understanding the source of dust in early galaxies. By observing two Type II supernovae, Supernova 2004et (SN 2004et) and Supernova 2017eaw (SN 2017eaw), scientists have discovered large amounts of dust within the ejecta of these objects. This finding supports the theory that supernovae played a crucial role in supplying dust to the early universe.
Dust is an essential building block for various objects in the universe, particularly planets. As dust from dying stars spreads through space, it carries essential elements that contribute to the formation of new stars and planets. However, the origin of this cosmic dust has puzzled astronomers for years. One potential source of cosmic dust is supernovae. When a star explodes, its leftover gas expands and cools, creating dust.
Until now, direct evidence of this phenomenon has been limited. The only supernova where the dust population has been studied is Supernova 1987A, which is located 170,000 light-years away from Earth. However, the dust formed in this supernova is only detectable at mid-infrared wavelengths with sufficient sensitivity.
To study supernovae that are more distant than SN 1987A, such as SN 2004et and SN 2017eaw, researchers needed the James Webb Space Telescope’s Mid-Infrared Instrument (MIRI). These observations mark a significant breakthrough in studying dust production from supernovae since the detection of newly formed dust in SN 1987A nearly a decade ago using the Atacama Large Millimeter/submillimeter Array (ALMA) telescope.
The researchers were not only able to detect dust but also measure its quantity at an early stage in the supernova’s life. In SN 2004et, they found over 5,000 Earth masses of dust. This measurement rivals the dust mass detected in SN 1987A, despite SN 2004et being much younger.
These findings have provided evidence that supernovae can produce and preserve dust despite the internal shocks that occur after the explosion. This suggests that supernovae are indeed significant dust factories.
The researchers also believe that the current estimations of dust mass may be just the beginning. While the James Webb Space Telescope has allowed them to measure cooler dust than ever before, there may be undetected, colder dust radiating even farther into the electromagnetic spectrum. This dust could be obscured by the outermost layers of dust.
Overall, these findings open up new research possibilities into supernovae and their dust production using the James Webb Space Telescope. Scientists are excited to explore what this dust implies about the core of the exploding star and how it can contribute to our understanding of stellar evolution.
The observations of SN 2004et and SN 2017eaw are part of a larger program that includes five targets. This research was conducted as part of Webb General Observer program 2666 and was published in the Monthly Notices of the Royal Astronomical Society on July 5th.