In 185, the ancient Chinese astronomers noticed a strange star who disappeared eight months. In 1960 we almost modern scientists have come to the conclusion that it was the first documented supernova recorded. It was designated SN 185. Later it remains recognized object RCW 86, located about eight thousand light-years from Earth.
But the mystery is not diminished by this: spherical residues were larger than usual. If we could see in the infrared region of the spectrum, they would occupy in our sky more space than a full moon.
Thanks to observations with the help of US space telescope "Spitzer" and WISE experts seem able to solve the age-old riddle of heaven.
The researchers combined the new data with the results of observations of the American space X-ray observatory "Chandra" and the European X-ray space telescope XMM-Newton. It was found that belonged to the type of supernova Ia. It was created by the relatively peaceful death of a sun-like star that has become a white dwarf. The latter, apparently exploded, engulfing nearby star material. "The white dwarf - like smoking embers extinct fire - says study author Brian Williams of North Carolina State University (USA). - If they throw gasoline explosion happen ».
Observations of the first to show that the white dwarf is able to create a cavity around it before flash SNe Ia. This may explain why the remains of SN 185 is so huge. When the explosion occurred, the ejected material is not met obstacles from the gas and dust and scattered in two to three times faster than usual.
The scientists were able to measure the temperature of the dust, the remainder of SN 185: about 73 K. It was then calculated how much gas could be heated to this temperature dust. Wednesday was a very tenuous that reinforced guess about the cavity.
Previously, experts suggest that the object RCW 86 was the result of the collapsed core. Hints of a cavity has been found, but then they were associated only with supernovae of type II. In such cases, massive stars blow away with a material before the explosion, with the result that there is a cavity.
This hypothesis had to be discarded because the data "Chandra" and XMM-Newton indicated that the object is largely made of iron, and it is a sure sign of type Ia.