Single object seems to be remnant of two close stellar explosions

Jan 11, 2008 14:25 GMT  ·  By

What seems to be a single object in the image provided by the Gemini Observatory is actually a structure formed by two separate different supernova explosions, which could have taken place about a few thousands years ago. The object located in the Large Magellanic Cloud was discovered in the early 1970 and classified as supernova remnant, originating in a single object that is composed of large quantities of gas and dust, ejected by an exploding star.

Similar shaped supernovae are relatively abundant in the universe, due to non-symmetric interactions between the ejected material during the explosions, that give them the distinctive bi-polar shape. This was the main reason why the remnant designated DEM L316 was originally catalogued as a single object. However, observations made with the Chandra and XMM Newton X-ray Space Telescopes revealed otherwise.

X-ray imaging of the two separate clouds of matter revealed that they had different chemical compositions, which could only be explained by the fact that they could have originated from separate explosions. The smaller cloud of material, seen in the lower left corner of the image, seems to have a considerably higher content in iron than the other larger remnant. Such high iron concentrations can only originate in white dwarfs that accumulate large amount of matter and blow themselves apart in the process.

According to Dr. Rosa Williams of the Columbus State University, the other larger material remnant could have been ejected by the explosion of a massive star, about seven times the mass of the Sun, at the end of its short life. Massive stars burn hydrogen fuel much more rapidly than stars comparable to the Sun, and have lives of only a few millions years.

The fact that the two remnants seem to originate from a single object is merely due to the expansion of the gas and dust clouds over time, and the observation angle of the structure that seems to be colliding from our point of view.

The galaxy known as the Large Magellanic Cloud is part of what we call the Local Group, representing the galaxy cluster from which the Milky Way is part. It is actually a satellite of our galaxy, and the third closest to the Milky Way, being only 160,000 light years away. The peanut-shaped supernovae remnants have extended into space about 140 light years, equivalent to nearly 35 times the distance from the Sun to the closest star.