New Discovery: Roundest Star In The Universe Found
A study conducted by a team of researchers lead by Laurent Gizon from the Max Planck Institute for Solar System Research and the University of Göttingen revealed that a distant star Kepler 11145123 is the roundest object in the universe.
Tech Times reported that star's roundness is usually measured by a technique called asteroseismology --- the study of the oscillations of stars --- where the difference between the star's equatorial and polar radii is calculated. On an average, a star's equatorial bulge is 1.5 million kilometers. Kepler 11145123 has an equatorial bulge of 3 kilometers, making it rounder than most.
Kepler 11145123 is located about 5,000 light-years away from planet Earth. It is more than twice the size of the sun and rotates three times more slowly than the Sun.
According to Space.com, round celestial bodies become flat and bulge slightly at their equators due to centrifugal force.The faster they spin, the greater the force, and the larger the bulge.
Gizon's team could measure the roundness of Kepler 11145123 because it has purely sinusoidal oscillations, meaning, the star's periodic expansions and contractions can be detected in its changing luminosity. The oscillation was measured by the Kepler Space Telescope over four years.
New Atlas cites that the possible explanation to this "perfect shape" is that there could be a magnetic field at lower latitudes of the star that acts like a sort of cosmic corset to counteract the centrifugal forces.
Meanwhile, the team said they intend to use the same method they used in Kepler 11145123 to study other stars with sinusoidal oscillations.
"We intend to apply this method to other stars observed by Kepler and the upcoming space missions TESS and PLATO. It will be particularly interesting to see how faster rotation and a stronger magnetic field can change a star's shape," Gizon adds, "An important theoretical field in astrophysics has now become observational."