Around a year ago, scientists released the first-ever photograph of a black hole, but they are now seeing an unexpected feature.
It is common knowledge that scientists are constantly learning and adapting due to new information. The first-ever image of a black hole is now potentially showing wobbling ring around the form, which is a new, unexpected feature.
In April 2019, we were first given access to the what was once thought to be unseeable – with everything that has happened in 2020, this feels like years ago. But it was only just over a year ago when we got to see a supermassive black hole for the first time.
While you can’t actually see the black hole, due to their nature of sucking in all available light, the picture does show us something we had never seen up to this point.
The picture depicts a lopsided ring, which scientists have stated is known as the black hole’s shadow, of extremely hot gas that is circulating the horizon of the black hole. The black hole’s event horizon is the boundary in which light can no longer escape.
The black hole that has been depicted in this image, located in the Messier 87 galaxy (M87*), approximately 55 million light-years away, has an estimated mass of 6.5 billion suns.
In April 2019, the black hole M87* was captured by the Event Horizon Telescope – a significant historic achievement of the 21st century.
The static view on M87* is a historic achievement, however, there has been new research into the image that has been released by the Astrophysical Journal stating that it is possible to actually study and understand the changes that take place over time to not only the physical nature of the black hole but to its entire surroundings.
Since the release of the image in April last year, Astronomers of the Event Horizon Telescope project have been trying to research the changes that occur with the black hole and attempt to track aspects of it – which, for the first week, proved unsuccessful. However, they began researching EHT archival data from as far back as 2009.
Centre for Astrophysics at Harvard & Smithsonian astronomer Maciek Mielgus says that “if you want to see a black hole evolve over a decade, there is no substitute for having a decade of data.”
The EHT is a very large telescope that is built out of strategically placed radio dishes and was fully operational in 2017. There are five dishes around the globe, which, according to a press release by the Max Planck Institute for Radio Astronomy, is said to have resulted in an “Earth-sized radio dish“.
While this system was being built, it was continuously gathering information about astrophysics that were extremely important. The observations that it collected from this enormous black hole was gathered over three sites between 2009 and 2012 and from four from 2013.
Authors of this new study state that “While these observations do not contain enough information to produce images, they are sufficient to constrain simple geometric models.”
Statistical modelling and educated guessing have resulted in researchers charting the changes that occurred to the black hole that the EHT gather up until 2019.
If you are a fan of Albert Einstein and his theories, you will be excited that the shape of the black hole has stayed constant over the past decade.
In the Harvard and Smithsonian press release, MIT scientist Kazu Akiyama states that “In this study, we show that the general morphology, or presence of an asymmetric ring, most likely persists on timescales of several years.” Continuing by writing, “This is an important confirmation of theoretical expectations as the consistency [of multiple observations] gives us more confidence than ever about the nature of M87* and the origin of the shadow.”
While the shape stayed constant, researchers did notice that the rings surrounding the black hole appear to wobble slightly – it’s shape hasn’t changed, but it appears to be rotating.
“Actually, we see quite a lot of variation there.”
“Data analysis suggests that the orientation and fine structure of the ring varies with time,” states Thomas Krichbaum, MPIfRA astronomer. This provides a “first impression on the dynamical structure of the accretion flow, which surrounds the event horizon.”
This study has allowed us to enter an entirely new phase in the study of black holes. Astronomers can now study the changes to these systems over the course of time.