In the journal “Science” an article was just published that discusses a research conducted by an international team of scientists who found evidence that supernovae can generate a sufficient amount of material that can later create new planets like Earth. This team, led by Ryan Lau of Cornell University in Ithaca, New York, studied in particular a supernova that exploded about 10,000 years ago using a special instrument, the airborne telescope SOFIA.
Flying observatories, with telescopes mounted on airplanes or balloons, are less famous than space telescopes but have existed for decades. SOFIA (Stratospheric Observatory for Infrared Astronomy) is a project of NASA and DLR, the German space agency, that uses a Boeing 747SP modified to allow the use of a telescope of 2.5 meters in diameter.
The SOFIA airborne telescope specializes in infrared astronomy thanks to the fact that at the altitudes at which flies, between 12 and 14 km (39,000 to 45,000 feet), there is much less water vapor to absorb that kind of light. This research used in particular its instrument FORCAST (Faint Object InfraRed Camera for the SOFIA Telescope) to obtain detailed images of the remnants of the supernova known as Sagittarius A East or SNR Sgr A East at infrareds.
In very distant galaxies, which appear to us as they were at a time when they were very young, astronomers found a lot of dust. It’s very likely originated in supernovae, also because evidence was already found that large amounts of dust could be created in a supernova.
The only question that remained was if that dust could survive the second shock wave. It’s the “bounce” shock wave, caused by the thermal pressure difference between the materials ejected from the supernova and the circumstellar medium, which is colder.
The SOFIA airborne telescope allowed to observe the remnants of the supernova Sagittarius A East, exploded about 10,000 years ago. These remains are near the center of the Milky Way, which means that they’re close enough to be studied and infer a more common general behavior also for stars exploded billions of years ago in very distant galaxies.
The observations allowed to estimate that an amount between 7% and 20% of the dust from the supernova survived the second shock wave. This estimate was performed through measurements at long infrared wavelengths of the dust cloud of Sagittarius A East. The intensity of the emission allowed to assess the total mass of the dust mass.
According to the researchers, the estimate of the dust that survived the second shock wave means more dust than expected may have been kept in conditions similar to those of the early universe. This confirms the hypothesis that the dust in the oldest galaxies was generated by supernovae.
The dust clouds have the potential to form new stars and especially the elements heavier than hydrogen and helium can form rocky planets. This is why we’re also children of ancient stars that exploded billions of years ago, forming elements that now are literaly part of us.