For the past few months the Hubble Space Telescope has been observing a cosmic feast. About 300 million light-years from us (relatively close in space terms), a supermassive black hole was engulfing a star that had gotten too close.
Almost 300 million light years away.
AT2022dsb is the name that astronomers have given to the event captured by Hubble, in which a black hole located in the center of the galaxy ESO 583-G004 shattered a star that got too close to the hole’s vicinity.
Events of this type are very intense but slow. When a star gets too close to a black hole, it is trapped by its gravity, after which a process called tidal disruption (or interruption) begins.
The name of the event is due to its resemblance to the effects of gravitational interaction between the Earth and the Moon that cause the tides. Only in this case, the tremendous gravitational pull deforms the attracted body (in this case a star) to the point of pulverizing it. The bits, hydrogen, carbon and some other elements that the star leaves behind remain orbiting the black hole, forming a donut-shaped ring. This is the phase of the disruption that Hubble has been able to observe.
From ultraviolet light.
Of course, the observation of Hubble has had its limitations. At 300 million light years, the veteran telescope has had to limit itself to analyzing the ultraviolet emissions of the event. Through these instruments, Hubble was able to perform ultraviolet spectroscopy over an extended period of time.
“There are still very few tidal events that are observed in ultraviolet light, given the observation time. This is really unfortunate because there is a lot of information that can be obtained from ultraviolet spectra,” Emily Engelthaler of the Harvard & Smithsonian Center for Astrophysics explained in a press release.
“We are excited that we can get these details about what the debris is doing. The tidal event can tell us a lot about a black hole,” added the astronomer.
Reconstruction of an event like the one observed by Hubble. NASA, ESA, Leah Hustak (STScI).
to X-rays.
X-rays. This latest event has provided a unique opportunity to observe this “feast” from the ultraviolet perspective. A few months ago, a similar event, AT2022dsb, was captured by telescopes that analyzed its emissions in another range of the electromagnetic spectrum, X-rays.
A long way to go.
Neither the arrival of the James Webb telescope nor future plans that include ambitious telescopes in the short and medium term have made Hubble lose its pace of work. Hubble still has a lot to offer, whether working in conjunction with Webb or on its own.
So much so that plans to extend the life of the veteran telescope are already on the table of those responsible for NASA. We will have to wait for now before knowing the final decision on this possibility, if we will see Hubble “refloated” towards an orbit that allows it to operate for a few more years (or decades) or if it will see its days ended by making a reentry into the Earth’s atmosphere in about 10 to 15 years.
Cover image | NASA/CXC/U.S. Michigan/J. Miller et al.; Illustration: NASA/CXC/M. Weiss