A supernova can occur in two ways; when the production of energy through nuclear fusion is suddenly stopped or started. Scientists estimate that supernovae occur about every 50 years in a galaxy the size of the Milky Way.

The puzzle for scientists and astronomers is that only six young supernovae have been found in our galaxy and more than 30 are predicted to have occurred at one every 50 years. A scientist named Stephen Reynolds, an astrophysicist at North Carolina State University, and his team have found what they describe as a very young supernova.

The supernova in question is called G1.9+0.3. Scientists predict that the supernova is only about 140 years old. Previously, the youngest supernova known to exist in our Milky Way galaxy was Cassiopeia A discovered in the 17th century.

Reynolds told National Geographic, Cas A had been the reigning youngest remnant for so long that it took a while to sink in that we had found something less than half its age.

The reason G1.9+0.3 went undiscovered for so long is that it was obscured by dust. The researchers say if the dust and gas around the supernova hadnt been so dense that people in the 1800s would have seen the supernova appear in the Sagittarius constellation.

The scientists say that G1.9+0.3 has increased by 16% in the last 22 years, which suggest an age for the supernova of 140 years. The estimated age was arrived at by comparing radio observations from the 1980s with 2007 images of the object from the Chandra X-Ray Observatory.

Reynolds adds, Normally, we deal with older remnants and have to work very hard to see even tiny changes. This supernova is getting brighter, which means it's still on its way up. Studying it will go a long way toward filling in gaps in our knowledge of these events and their effect on galaxies."

Reynolds and his team have submitted a proposal for a longer observation period for the G1.9+0.3 supernova using Chandra. Reynolds says, We've just never had the opportunity to study a remnant in this phase of its life. Now that we know how fast it's changing, it will be useful to re-observe it again and again and watch its evolutionpretty rare for an astronomical event!"


In March of 2008 light and gamma rays from a supernova explosion that occurred billions of years ago finally reached the Earth and set a record for the most distant object from Earth seen with the naked eye.