Researchers have always wanted to measure the elusive properties of a black hole. A new unified model that explains how a black hole consumes stellar material may help them do exactly just that.
A team of astrophysicists from the DARK Cosmology Center at the Niels Bohr Institute of Copenhagen University and the University of California Santa Cruz have built a new computer model that shows what it looks like when a star gets too close to a massive black hole and is devoured by its super-strong gravitational pull.
The event is called a tidal disruption event (TDE), a rare, cataclysmic cosmic event that happens only once in 10,000 years, although new research may challenge this theory.
What Are Tidal Disruption Events?
In the middle of every galaxy lies a giant black hole that is ready to devour whatever comes its way. However, in most galaxies, black holes are for the most part inactive. They only get to show some activity observable to observers on Earth when another object comes along and it gets pulled inside the black hole.
That happens every 10,000 to years or so, when an unfortunate star wanders a tad bit too close to a black hole and gets swallowed into the unknown. Only 24 of these events have since been recorded in human history, making it quite a challenge for astronomers to observe TDEs and measure the properties of a black hole.
However, the model invented by astrophysicist Jane Lixin Dai and her team will provide scientists with a new framework to help them understand black holes and how they eat up objects in space.
Death By Black Hole
When a star gets swallowed by a black hole, it is too dense to get eaten up entirely. Instead, it forms into a disk and huge amounts of light and radiation are emitted. It is this radiation that can be observed by scientists.
"This makes it extremely interesting to go hunting for tidal disruption events," Dai says.
However, researchers have encountered huge variations among the 24 recorded TDE observations. For instance, one black hole emitted X-rays, while others gave off ultraviolet rays or visible light. It is these variations that are posing a difficulty for scientists trying to study black holes.
New Model To Unify Black Hole Knowledge
What accounts for these variations, then? Dai and her team believe the viewing angle provides the differences in observations. Galaxies are aligned differently in space, according to where the observer is located on Earth. Scientists see different aspects of an event depending on the alignment of the galaxy in space.
"It is like there is a veil that covers part of a beast," explains Enrico Ramirez-Ruiz, coauthor and chair of the astrophysics program at the Niels Bohr Institute. "From some angles we see an exposed beast, but from other angles we see a covered beast. The beast is the same, but our perceptions are different.
The new model shows what researchers will likely see from various angles. This will help them put multiple varying events into a single framework and unify the knowledge currently available on black holes.
The researchers have published their study in Astrophysical Journal Letters.