Supernovae have been discovered that are the brightest ever. They are cosmic explosions that are much bigger than just basic novae. Although they may burn for months or only a few weeks, during this time period a supernova can emit as much energy as the Sun is believed it will release over its whole life span. Now, it appears that there are a couple more that have happened to put down in the record books. Astronomers, who are associated with the Supernova Legacy Survey, have found two of the brightest, but also most distant supernovae that have ever been recorded. They are each located at least 10 billion light-years away and are over a hundred times more radiant than any regular supernova.
Supernovae are typically caused by massive stars disintegrating into black holes or neutron stars, and in these two cases, they have scientists shaking their heads. According to the astronomers, the ordinary mechanism for producing supernovae is unable to explain why these two supernovaes are so exceptionally bright. They were so shiny when they were each discovered in 2006 and 2007, respectively, that astrophysicists were not completely sure what exactly they even were.
The research study lead author D. Andrew Howell, who is also a staff scientist at the Las Cumbres Observatory Global Telescope Network, stated that at first his team had no idea what they were looking at, if they were supernovae and if they were even in Earth’s own galaxy or a very distant one. He added that he showed their findings at a space conference, and everybody there was also perplexed. No one guessed that they were faraway supernovae because they would have had to have been mind numbingly large based on the size of the energy they each were producing. It was believed to be impossible.
One of the supernovae was given the “catchy” name “SNLS-06D4eu.” It is so bright that it has produced a totally new class of supernovae that is called “superluminous supernovae.” Such new models belong to a special class of supernovae which do not have any hydrogen, but are the brightest supernovae ever discovered.
The newest study had discovered the supernovae are probably powered by the formation of a magnetar, which is an extraordinarily magnetized star that is spinning at least hundreds of times per second. Magnetars are extremely dense, with the mass of the Sun crammed into a star that is about the size of a city from Earth. Though magnetars have been assumed to be the source of these types of supernovae, this study is the first to ever match observations with what such an explosion could possibly look like.
The supernovae were so far away that the ultraviolet light released during the explosion was overextended by the universe’s expansion until it increased in wavelength to the part of the spectrum where it shows up in the lens of telescopes on Earth. This explained why astronomers were at first mystified by the observations. They had never seen a supernova so far in UV before.
The supernovae burst back when the universe was 4 billion years old, yet their light is just reaching us now. These events happened before the Sun even existed. Another star had existed here which died and whose gas cloud ended up creating the Sun and Earth.
These supernovae are dinosaurs and are basically extinct in this day and time, but they happened more frequently during the early times of the universe. Astronomers are lucky to be able to use telescopes to be able to look back in time and study such fossil light. Scientists are hoping to be able to discover many more of such kinds of these bright supernovae with ongoing studies and research.
By Kimberly Ruble