Analysis of the Radiation of a Supernova SN1987A

According to european and american scientists analysis of the radiation of a supernova SN1987A in the Large Magellanic Cloud the gas cloud, which was formed by an explosion, lights not only by radioactive decay of its matter, but under the influence of X-rays.Second type supernova SN1987A is located relatively close at a distance of 160,000 light years from Earth. SN1987A is the result of an explosion of blue supergiant Sk-69/202. It is believed that the cloud of gas from the supernova explosion continues to glow for some time.The behavior of SN1987A consistent with this rule until 2001, but after that the luminosity of the clouds began to increase. 

Astronomers have concluded that the  current growth of the luminosity can be explained by a release  of  energy in a result of collision of a cloud of expanding gas with the clusters of ionized hydrogen, which could be thrown by SN1987A’s progenitor star, shortly before the explosion.Scientists have compared the two models of nebula developemenet, in which the main source of energy were the decay of radioactive elements and heat of a gas cloud as a result collision with ionized hydrogen. They think that the SN1987 has passed from the phase of the radioactive heating to the phase where the main source of energy is in favor X-rays. Gas cloud absorbs most X-ray and spends part of the received energy to the emission of light in the visible range.