Researchers have discovered a "hypervelocity star" that is the closest, second-brightest and among the largest of 20 found so far.
According to astronomers, speeding at more than 1 million miles per hour (mph), the star may provide clues about the supermassive black hole at the center of our Milky Way and the halo of mysterious "dark matter" surrounding the galaxy.
Zheng Zheng, an assistant professor of physics and astronomy and lead author of the study, said the hypervelocity star tells us a lot about our galaxy-especially its center and the dark matter halo.
Zheng said that they can't see the dark matter halo, but its gravity acts on the star, asserting that they gain insight from the star's trajectory and velocity, which are affected by gravity from different parts of Milky Way.
Zheng and his colleagues discovered the new hypervelocity star while conducting other research into stars with the Large Sky Area Multi-Object Fiber Spectroscopic Telescope, or LAMOST, located at the Xinglong Observing Station of the National Astronomical Observatories of China, about 110 miles northeast of Beijing.
Despite being the closest hypervelocity star, it nonetheless is 249 quadrillion miles from Earth. (In U.S. usage, a quadrillion is 1,000,000,000,000,000 miles, or 10 to the 15th power, or 1 million billion.)
A cluster of known hypervelocity stars, including the new one, is located above the disk of our Milky Way galaxy, and their distribution in the sky suggests they originated near the galaxy's center, Zheng says.
The study has been published in the Astrophysical Journal Letters.
