A huge ball of glowing gas has been found billions of light-years away. It is brighter than hundreds of billions of Suns. We can’t think of anything like that. Astronomers have a hard time describing this object because it shines so brightly. Scientists aren’t sure what this thing really is, which is the most interesting thing about it. But they have different ideas.
At first, it was thought that ASASSN-15lh could be a magnetar, which is a very rare type of supernova remnant. But the size of it goes against the laws of physics. Krzysztof Stanek, an astronomy professor at Ohio State University, says that if there was a scale of brightness power from 1 to 10, this object would shine with a power of 11. This is impossible and goes beyond any existing units of measurement.
The Worldwide Automatic Supernova Survey (ASAS-SN), a small group of telescopes used to find bright things in the universe, was the first to find the object. Even though this object is very bright, you can’t see it with your eyes because it’s 3.8 billion light years away.
Try to explain what the ASASSN-15lh is.
Since 2014, almost 250 supernovae have been found by ASAS-SN. But the discovery of ASASSN-15lh stands out because of how powerful it is. A supernova is 200 times stronger than a normal one, 570 billion times brighter than the Sun, and 20 times brighter than all the stars in the Milky Way put together.
One idea comes from Ohio State professor of astronomy Todd Thompson. A millisecond magnetar is a very rare type of star that could be made by a supernova. It spins so fast that it makes a magnetic field that is very strong. But for this rare magnetar to be so bright, it has to spin at least 1,000 times per second and turn almost all of that rotational energy into light. But Krzysztof Stanek thinks that this is still the supermassive black hole at the center of an active galaxy.
In the future, the Hubble Space Telescope will try to figure out what this object is, giving astronomers a chance to look at it closely.