You've probably read about the recent findings about the Type 1a Supernova 2011fe, 21 million light years away, near the Pinwheel Galaxy, which became visible in August. A team of astronomers from the University of California Berkley has concluded that because the PIRATE telescope in Majorca, Spain, wasn't able to detect the supernova just hours after it exploded (setting a new lower limit on the size of the star which exploded), the star must have been a white dwarf.
But while they were sure that a companion star was feeding into the white dwarf, the composition of that companion star was unknown.
Meanwhile, however, astronomers from Louisiana State University in Baton Rouge have been studying SNR0509-67.5 (pictured above in a composite optical and X-ray NASA photograph), the remnant of a Type 1a supernova in the Large Magellanic Cloud, the light from which first reached Earth 400 years ago. They identified the center of that beautifully symmetrical bubble as the likely site of the explosion and, since a large companion star would have survived the explosion and been flung away on a predictable course, searched for that star where it would inevitably be four centuries after the explosion.
Nowhere in that region, however, did they find any stars. Leading them to the only possible conclusion, which is that the companion star had also been a white dwarf, subsequently destroyed in the supernova.
A neat bit of scientific fact-crunching and kudos to all involved.
As a science fiction writer, however, it seems obvious to me that this is not the only possible explanation. My first thought is that an interstellar war went very hot and that the only way to end it was to eliminate the home system of one side. My second thought is that a religious war on the home planet went auto-genocidal with identical results.
Nobody in the scientific community is going to take either of those speculations seriously, of course. But I have to wonder: Has anybody ever taken the number of supernovae per trillion stars and factored it into the Drake Equation? It could be a very tidy solution to the Fermi Paradox.
Above: Credits: X-ray: NASA/CXC/SAO/J.Hughes et al, Optical: NASA/ESA/Hubble Heritage Team (STScI/AURA)