When neutron stars collide, they cause an explosion in the shape of a perfect sphere, contrary to what was believed until recently. How this is possible is still a mystery, but the discovery could provide new clues to fundamental physics and measuring the age of the universe. The discovery was made by astrophysicists from the University of Copenhagen and was published in a journal. Nature.

Cylons—the giant explosions that occur when two neutron stars orbit and eventually collide—are responsible for creating both big and small things in the universe, from black holes to the atoms in the gold ring on your finger, to the iodine in our bodies. They create the most extreme physical conditions in the universe, and the universe creates the heaviest elements in the periodic table, such as gold, platinum, and uranium, in these extreme conditions.

But we still don’t know much about this violent phenomenon. When a Kilonova was discovered 140 million light-years from Earth in 2017, scientists were able to gather detailed data for the first time. Scientists from around the world, including Albert Snappen and Darach Watson of the University of Copenhagen, who made the startling discovery, are still interpreting data from this massive explosion.

“You have two supercompact stars orbiting each other 100 times per second before they collapse. Albert Snappen, a postdoctoral fellow at the Niels Bohr Institute and lead author of the study published in the journal, says our intuition and all previous models suggest that the explosion cloud formed by the collision should have a flat and highly asymmetrical shape. Nature.

So he and his fellow researchers were surprised to find that this wasn’t the case for the landmark 2017. It is completely symmetrical and has a shape close to the ideal sphere.

“No one expected the explosion to be like this. It doesn’t make sense for it to be spherical like a ball. But our calculations make it clear that it is. It probably means that the kilonova theories and simulations we’ve been studying for the past 25 years are missing important physics,” said Darach Watson, associate professor at the Niels Bohr Institute and the study’s second author. ” says.

About Kilonov

• Neutron stars are extremely compact stars composed mainly of neutrons. They usually have a diameter of only 20 kilometers, but can be one and a half to two times heavier than the Sun. A teaspoon of neutron star material is roughly the size of Mount Everest.
• A kilonova event occurs when two neutron stars collide. That’s the name of the giant explosion that created the fusion. It is a radioactive fireball that expands at a tremendous speed and consists mostly of heavy elements formed during fusion and then both lighter and very heavy elements that are blasted into space.
• This phenomenon was predicted in 1974 and was first clearly observed and described in 2013. In 2017, detailed data from the kilonova were obtained for the first time, when the LIGO (in the USA) and Virgo (in Europe) detectors succeeded in measuring the gravitational phenomenon in a sensational way. Waves from kilonova AT2017gfo located in a galaxy 140 million light-years away.

Spherical shape is a mystery

But how a kilonova can become spherical is a real mystery. According to the researchers, the game should have an unexpected physics:

“The most likely way to make an explosion spherical is to release a large amount of energy from the center of the explosion and flatten the shape that would otherwise be asymmetrical. So the spherical shape tells us that there is probably a lot of unexpected energy at the center of the collision,” says Albert Snappen.