NASA Telescopes Solve 2,000-Year-Old Supernova Puzzle
The mystery of the first documented report of star explosion, that of an ancient supernova spotted nearly 2,000 ago, has been solved by NASA space telescopes.
New infrared observations from the Spitzer Space Telescope and Wide-field Infrared Survey Explorer reveal how the first supernova ever recorded occurred and how its shattered remains ultimately spread out to vast distances.
The star mysteriously appeared in the sky in 185 A.D. and stayed for about eight months, according to the observations of ancient Chinese astronomers. By the 1960s, scientists had determined that the mysterious object was the first documented supernova.
Scientists later pinpointed RCW 86 as a supernova remnant located about 8,000 light-years away. However a puzzle remained because the star's spherical remains are larger than expected. If they could be seen in the sky today in infrared light, they'd take up more space than a full moon.
According to NASA, infrared views of the supernova from the two space telescopes reveal that the star detonated inside a region of space that was relatively free of gas and dust, and which allowed the explosion to travel out much farther and faster than expected.
The findings reveal that the event is a "Type Ia" supernova, created by the relatively peaceful death of a star like our sun, which then shrank into a dense star called a white dwarf. The white dwarf is thought to have later blown up in a supernova after siphoning matter, or fuel, from a nearby star.
Brian Williams, an astronomer at North Carolina State University and lead author of the new study, said the supernova remnant "got really big, really fast."
"It's two to three times bigger than we would expect for a supernova that was witnessed exploding nearly 2,000 years ago. Now, we've been able to finally pinpoint the cause," he added.
Astronomers were able to grasp the missing pieces of the puzzle by combining new data from Spitzer and WISE with existing information from NASA's Chandra X-Ray Observatory and the European Space Agency's XMM-Newton Observatory.
