About 150 million light-years far from the Earth, two galaxies collided, dubbed Arp 299. Upon this collision, the giant black hole of 20 million solar masses, from the center of one of the two galaxies, torn apart a star twice as big as the Sun. For the first time, astronomers recorded the whole event, the so-called tidal disruption event, with the National Science Foundation’s Very Long Baseline Array (VLBA).
Scientists theorized that during a tidal disruption event the matter sucked by the black hole generates a swirling disk around the event horizon and the black hole emits X-Ray and visible light. However, the recently recorded event revealed more details about the way a black hole absorbs stars.
“Never before have we been able to directly observe the formation and evolution of a jet from one of these events,” told Miguel Perez-Torres from the Astrophysical Institute of Andalusia, in Granada, Spain.
Tidal disruption event recorded by astronomers, as a giant black hole torn apart a star
The first evidence that a star was going to be absorbed by the giant black hole popped up in January 2005 when the William Herschel Telescope in the Canary Islands recorded a bright and robust emission in infrared, originating from the center of one of the two colliding galaxies in Arp 299.
Later, in July 2005, Very Long Baseline Array (VLBA) telescope showed that there is also another source of radio waves emissions, in the same location.
“As time passed, the new object stayed bright at infrared and radio wavelengths, but not in visible light and X-rays. The most likely explanation is that dense interstellar dust and gas near the galaxy’s center absorbed the X-rays and visible light, then re-radiated it as infrared,” explained Seppo Mattila.
The astronomers followed this tidal disruption event (TDE) for over a decade, and continuous observation with VLBA, the European VLBI Network (EVN), as well as other radio telescopes around the world, revealed that the emissions emerged into one direction, a fact that is a proof of that a TDE was underway. Now, the astronomers involved in this project came up with
Studying a tidal disruption event can assist astronomers in learning more about the galaxies formation which happened billions of years ago.