Front-Row Seats to Star’s Death by Spaghettification

Astronomers captured the final moments of a star just before it was torn apart by one black hole. The violent event – called a tidal disruption event – created a burst of light that was seen only 215 million light years from Earth. This is the next such torch recorded to date. The research is published in the monthly releases of the Royal Astronomical Society.

“The idea that a black hole ‘sucks in’ a nearby star sounds like science fiction. But that’s exactly what happens in a tidal disruption event, ”said Matt Nicholl, senior lecturer and research fellow at the Royal Astronomical Society University of Birmingham, UK, and the lead author of the new study.

For a detailed look at what happens when a star is engulfed by a monstrous black hole, the researchers pointed to the European Southern Observatory Very large telescope (VLT) and New Technology Telescope (NTT) on a new flash of light that occurred near a supermassive black hole last year. Follow-up observations were made over a period of six months at multiple telescopes around the world, including the Harvard & Smithsonians Center for Astrophysics, MMT at the Fred Lawrence Whipple Observatory in Amado, Arizona.

This graphic shows the location of AT2019qiz, a tidal disruption event, in the constellation Eridanus. The map contains most of the stars that are visible to the naked eye in good conditions, and the location of AT2019qiz is indicated by a red circle. Photo credit: ESO, IAU, and Sky & Telescope

Tidal disturbance events – where stars experience spaghettification – are powerful and bright, which should make them easier to study. “A tidal disruption event results from the destruction of a star that is too close to a supermassive black hole,” said Edo Berger, astronomer. CfAand one of the authors of the study. “In this case, the star was torn apart, with about half of its mass injected or accumulated in a black hole a million times the mass of the Sun, and the other half ejected outward.”

These rare events are often obscured by a thick curtain of dust and debris, which until now has made it difficult for astronomers to see what is happening. AT2019qiz – the tidal disruption event studied by the team – was found shortly after the star ruptured, making analysis easier. “Because we saw it early on, we were actually able to see the curtain of dust and debris pull together as the black hole triggered a heavy flow of material at speeds of up to 10,000 km / s,” said Kate Alexander. NASA Einstein Fellow at Northwestern University. “This is a unique behind-the-scenes look that provided the first opportunity to determine the origin of the opaque material and watch it in real time as it devours the black hole.”

This picture shows the sky around the location of AT2019qiz in the center of the frame. This image was created from images in the Digitalized Sky Survey 2. Photo credit: ESO / Digitalized Sky Survey 2. Credits: Davide De Martin

The newly discovered tidal disruption event will help scientists better understand supermassive black holes and the behavior of matter around them. “AT2019qiz is the next tidal disturbance event to be detected so far, so it is incredibly well observed across the electromagnetic spectrum. This is the first case where we see direct evidence of outflowing gas during the interruption and accretion process, which explains both the optical and radio emissions that we have seen in the past, ”said Berger. “So far the nature of these emissions has been hotly debated, but here we see that the two regimes are linked by a single process. This event teaches us the detailed physical processes of accretion and mass ejection from supermassive black holes. ”

Read telescopes to record the final moments of the star engulfed by a black hole to learn more about this story.

Reference: “A runoff drives the optical rise of the nearby, rapidly evolving tidal disturbance event AT2019qiz” by M. Nicholl, T. Wevers, SR Oates, KD Alexander, G. Leloudas, F. Onori, A. Jerkstrand, S. Gomez , S. Campana, I. Arcavi, P. Charalampopoulos, M. Gromadzki, N. Ihanec, PG Jonker, A. Lawrence, I. Mandel, S. Schulze, P. Short, J. Burke, C. McCully, D. Hiramatsu, DA Howell, C. Pellegrino, H. Abbot, JP Anderson, E. Berger, PK Blanchard, G. Cannizzaro, TW Chen, M. Dennefeld, L. Galbany, S. González-Gaitán, G. Hosseinzadeh, C. Insra, I. Irani, P. Kuin, T. Müller-Bravo, J. Pineda, NP Ross, R. Roy, SJ Smartt, KW Smith, B. Tucker, yr Wyrzykowski and DR Young, October 12, 2020, Monthly releases from the Royal Astronomical Society.
DOI: 10.1093 / mnras / staa2824

Spaghettification

In astrophysics, spaghettification (sometimes called the noodle effect) is the vertical stretching and horizontal compression of objects into long thin shapes (similar to spaghetti) in a very strong inhomogeneous gravitational field; it is caused by extreme tidal forces. In the most extreme cases, near black holes, the stretch is so great that no object can withstand it, no matter how strong its components are. Within a small area, the horizontal compression compensates for the vertical stretch, so that small objects that become spaghetted do not experience any net change in volume.

Stephen Hawking described the flight of a fictional astronaut who is “stretched like spaghetti” within the event horizon of a black hole by the gravitational gradient (force difference) from head to toe. The reason for this would be that the gravity exerted by the singularity is much stronger on one end of the body than on the other. If you fell into a black hole first, gravity would be much stronger on their feet than on their head, which would cause the person to be stretched vertically. At the same time, the right side of the body is pulled to the left and the left side of the body to the right, which squeezes the person horizontally. However, the term “spaghetti” was introduced long before that. The spaghettification of a star was first pictured in 2018 by researchers observing a pair of colliding galaxies approximately 150 million light-years from Earth.