Scientists reveal new images of a black hole - Proof of a persistent black hole shadow

The Event Horizon Telescope Collaboration has released new images of the supermassive black hole at the centre of the galaxy Messier 87. Researchers from Aalto University and the University of Turku contributed to forming the images from the new observations.
Two images of the black hole M87. A bright orange ring surrounding the black hole.
The new 2018 observations reveal a bright emission ring around the black hole of the same size as in 2017, with the brightest part of the ring shifted by about 30 degrees between observations.

The Event Horizon Telescope (EHT) researchers published the first image of a black hole and its shadow in 2019, showing a bright ring with a dark circular area in the centre, the shadow of the black hole. 

The groundbreaking image showed that the giant galaxy Messier 87 has a supermassive black hole M87* at its centre. The black hole resides 55 million light-years from Earth.

Now, the research team has published a new image of the M87* black hole based on more recent and more precise observations taken in 2018. With the participation of the newly commissioned Greenland Telescope and a dramatically improved recording rate across the array, the 2018 observations give us a view of the source independent from the first observations in 2017.

According to the theory of general relativity, the size of the ring around a black hole depends mainly on the mass of the black hole. Based on this, the researchers assumed that the ring in the new image remains the same. 

The new images show the M87* black hole with a bright ring around it, similar to and the same size as the one observed in 2017. This result confirms the research team's earlier breakthrough.

Confirmation of the ring in a completely new data set is a huge milestone for our collaboration.

Dr. Keiichi Asada

“A fundamental requirement of science is to be able to reproduce results,” says Dr. Keiichi Asada, an associate research fellow at Academia Sinica Institute for Astronomy and Astrophysics in Taiwan.  “Confirmation of the ring in a completely new data set is a huge milestone for our collaboration and a strong indication that we are looking at a black hole shadow and the material orbiting around it.”

The image now released confirms the original findings, but there are also small differences between the images. 

"The brightness peak at the bottom of the ring has shifted by about 30 degrees. This observation supports our idea that there is a turbulent, magnetized accretion flow around the black hole, variations of which are causing the location of the brightness peak to fluctuate between the observations," says Tuomas Savolainen of Aalto University, who was involved in the study. 

Researchers from Aalto University and the University of Turku participated in the calibration and analysis of the EHT data and contributed to forming the images from the new observational data.

"We used both traditional algorithms and new methods based on statistical analysis to create the images. When using the new statistical methods, we also made use of the CSC supercomputers to generate the images. The computing time used was equivalent to a thousand years on a single laptop computer," says Kaj Wiik from the University of Turku.

Venkatessh Ramakrishnan from the Finnish ESO Centre also participated in the study. The EHT collaboration involves more than 300 researchers from around the world. The international collaboration is working to capture the most detailed black hole images ever by creating a virtual Earth-sized telescope.

The study is published in the journal Astronomy & Astrophysics.

More information:

EHT Press release 

Research article

Read more about black holes

Astronomers capture first image of a black hole

Aalto University contributed to paradigm-shifting observations of the gargantuan black hole at the heart of distant galaxy Messier 87

Kuva mustasta aukosta

Astronomers image a black hole’s shadow and powerful jet together for the first time

Aalto’s Metsähovi Radio Observatory took part in capturing the new image.

Teleskooppiverkoston ottama kuva galaksin M87 mustan aukon varjosta ja suihkusta.

Are black holes really black? True or false: five claims about black holes

Senior researcher Tuomas Savolainen addresses some common beliefs about black holes.

Taiteilijan näkemys mustasta aukosta.

A photo of a black hole was a distant dream – until now

Aalto’s Tuomas Savolainen helped make history with the first image of a black hole located 55 million light years away

Tuomas Savolainen
  • Published:
  • Updated:

Read more news

Dark-haired woman in dark dress standing outdoors with Otaniemi campus on a summer day
Research & Art Published:

Satu Lähteenoja: ‘Futures thinking and co-design are needed for advancing sustainability transformations in governance and politics’

In the I claim series Satu Lähteenoja shows that the transition arena method increases the understanding of systemic change among civil servants and decision-makers and helps them to think further into the future.
Jar full of coins representing Unite! Seed Fund.
Cooperation, Research & Art, Studies Published:

Call for proposals: Unite! Seed Fund to foster collaborative teaching

This call is for setting up joint/collaborative teaching formats in Unite! focus areas. Apply by end of August 2024.
Aalto University Junior technology workshop
Cooperation, Research & Art, University Published:

Automation Foundation donates to Aalto University Junior

Automation Foundation donates to Aalto University Junior. A donation of twenty thousand euros has been targeted at the purchase of virtual glasses and the renewal of robotics.
Timo Vuori
Research & Art Published:

Five things leaders should know about the power of emotions in watershed moments

Associate Professor Timo Vuori explains how to turn harmful anxiety into constructive energy