By: Derek Sun
Astronomers have discovered the “fastest moving star” in the universe. They say it orbits a black hole in a new fastest time. The star, called S4716, orbits near the Sagittarius A black hole at the center of the Milky Way Galaxy.
Astronomers have found that the star orbits the black hole, which is 23.5 million kilometers across, in just 4 years, meaning that it travels nearly 5,000 miles a second. The star was discovered by scientists at the University of Cologne and Masaryk University. They used five telescopes to observe the star, four of which were combined into a larger and more powerful telescope.
After inspecting the black hole for almost 2 decades, the researchers figured out the star’s speed. "For a star to be in a stable orbit so close and fast in the vicinity of a supermassive black hole was completely unexpected and marks the limit that can be observed with traditional telescopes," said Dr. Florian Peissker, the leader of the new study.
Additionally, the researchers found that the star could be as close as 100 AU (Astronomical Units), or roughly 9.3 billion miles. One AU, about 93 million miles is a very small distance in the astronomical index.
The S4716 star is part of a group of tightly packed group of stars called the S-star cluster or the Sagittarius A* cluster that contains around 100 speedy stars.
A black hole forms when a massive star dies. A star needs to be about 25 times more massive than the Sun to turn into a black hole. The star will compress into itself under its own weight and will have an infinite pull of gravity that even light cannot escape.
Every time a black hole sucks up an object, it grows a little bit. A black hole can grow big enough to swallow entire stars and galaxies! The star is located 26,000 light years away, which means that we are looking at the star 26,000 years ago! Space is so big that even light from the center of our own galaxy still takes 26,000 years to reach us, not to mention billions and billions of other galaxies.