3 Powerful Earth-based telescopes used to study the event A supernova 21 million light years away has offered a rare glimpse of how exploding stars can breathe life into the universe. Scientists captured images of  the titanic blast just 11 hours after the explosion in an outer spiral arm of the Pinwheel Galaxy in the Great Bear constellation.

Three powerful Earth-based telescopes and the American space agency Nasa's Swift orbital observatory were used to study the event, dubbed SN 2011fe.
The results produced a wealth of data, showing in unprecedented detail how heavier elements such as oxygen and iron were flung out of the expanding fireball.
In time, these elements will become building blocks of new solar systems and possibly their living inhabitants.
The observations also provided important clues to how this class of stella explosion, known as a Type 1a supernova, occurs.
Type 1a supernovae are important because they always produce the same amount of light. This has allowed astronomers to use them as "cosmic candles" to determine the size and rate of expansion of the universe.
From their brightness or dimness, astronomers can work out how far away Type 1 supernovae are, as well as the patch of universe around them.
But precisely how the explosions occur has long been an unsolved mystery.
Professor Shri Kulkarni, from the California Institute of Technology, US, one of the authors of the research published in the journal Nature, said: "What caused these explosions has divided the astronomical community deeply. SN2011fe is like the Rosetta Stone of Type 1a supernovae."