It’s a brilliance that surpasses the barrier of physical energy. Brighter than hundreds of billions of suns, a giant ball of hot gas is billions of light years away. It’s hard to imagine anything this great. So what is it? They have several possibilities, but astronomers aren’t entirely sure. They speculate that it could be a magnetar, a very rare type of supernova that pushes the energy limits of physics. In other words, it could be the most intense supernova ever observed.
This object is so bright that astronomers have a hard time finding ways to explain it. Krzysztof Stanek, an astronomy professor at Ohio State University and the team’s co-principal investigator, said, “If it’s really a magnetar, it’s like nature turned everything we know about the magnetar into 11. A chart on a scale of 1 to 10.
The object was first discovered by the Automated All Sky Survey of Supernovae (ASAS-SN, or “Assassin”), a small network of telescopes used to detect bright objects in space. Although this object is incredibly bright, it is 3.8 billion light-years away and cannot be seen with the naked eye. ASAS-SN has detected nearly 250 supernovae since its launch in 2014, but this discovery, ASASSN-15lh, stands out for its size. It’s 200 times brighter than an average supernova, 570 billion times brighter than her Sun, and 20 times brighter than all the stars in the Milky Way combined.
“We have to ask, how is that possible?” Stanek said. “It takes a lot of energy to shine bright, and that energy has to come from somewhere.”
Todd Thompson, an astronomy professor at Ohio State University, offers a possible explanation. Supernovae may have created a very rare type of star called a millisecond magnetar. This is a fast rotating, very dense star with a very strong magnetic field.
Magnetar is crazy like this:To shine this bright, this magnetar would have to spin at least 1,000 times per second, converting all the rotational energy into light with nearly 100% efficiency. The most extreme example of a physically possible magnetar.
“Given these limitations, would you ever see anything brighter than this?” Thompson said. If it really is a magnetar, the answer is basically no.”
In the coming months, the Hubble Space Telescope will try to solve this mystery by giving astronomers time to look at the host galaxy surrounding the object. The team has located this bright object at the center of a massive galaxy. This means that the object is not a magnetar, and the gas around it is actually evidence of a supermassive black hole.
If so, the bright light could be explained by a new type of event, says study co-author Christopher Kochanek, an astronomy professor at Ohio State University. It will be something never seen before in the center of the galaxy. Whether it’s a magnetar, a supermassive black hole, or something else entirely, the results are likely to prompt new ideas about how objects in the universe form.