Press releases


Mar 24 2021

11 telescopes around the world combined to research the core of a galaxy 55 million light-years away

Astronomers Image Magnetic Fields at the Edge of M87’s Black Hole

Scientists of the Event Horizon Telescope (EHT) collaboration - among them astrophysicist Luciano Rezzolla and his team from Goethe University Frankfurt - have revealed today a new view of the massive object at the centre of the M87 galaxy: how it looks in polarised light. This is the first time astronomers have been able to measure polarisation, a signature of magnetic fields, this close to the edge of a black hole. The observations are key to explaining how the M87 galaxy, located 55 million light-years away, is able to launch energetic jets from its core – jets, that are about one million light years large.

FRANKFURT. Luciano Rezzolla, Professor of Theoretical Astrophysics at Goethe University Frankfurt, says: “Understanding what powers relativistic jets in galaxies is a long-standing open question in astrophysics. The jets in M87 are enormous and they would cover 10 per cent of our galaxy, for example. The challenging observations from the ETH telescopes, combined with the theoretical simulations carried out in Frankfurt, are now providing essential information on comparatively small length-scales: For the first time we are looking at what the magnetic field looks like that close to the black hole.

“We are now seeing the next crucial piece of evidence to understand how magnetic fields behave around black holes, and how activity in this very compact region of space can drive powerful jets that extend far beyond the galaxy," says Monika Moscibrodzka, Coordinator of the EHT Polarimetry Working Group and Assistant Professor at Radboud University in the Netherlands.

On 10 April 2019, scientists released the first ever image of a black hole, revealing a bright ring-like structure with a dark central region — the black hole's shadow. Since then, the EHT collaboration has delved deeper into the data on the supermassive object at the heart of the M87 galaxy collected in 2017. They have discovered that a significant fraction of the light around the M87 black hole is polarised.

“This work is a major milestone: the polarisation of light carries information that allows us to better understand the physics behind the image we saw in April 2019, which was not possible before," explains Iván Martí-Vidal, also Coordinator of the EHT Polarimetry Working Group and GenT Distinguished Researcher at the University of Valencia, Spain. He adds that “unveiling this new polarised-light image required years of work due to the complex techniques involved in obtaining and analysing the data."

Light becomes polarised when it goes through certain filters, like the lenses of polarised sunglasses, or when it is emitted in hot regions of space that are magnetised. In the same way polarised sunglasses help us see better by reducing reflections and glare from bright surfaces, astronomers can sharpen their vision of the region around the black hole by looking at how the light originating from there is polarised. Specifically, polarisation allows astronomers to map the magnetic field lines present at the inner edge of the black hole.

“The newly published polarised images are key to understanding how the magnetic field allows the black hole to 'eat' matter and launch powerful jets," says EHT collaboration member Andrew Chael, a NASA Hubble Fellow at the Princeton Center for Theoretical Science and the Princeton Gravity Initiative in the US.

The bright jets of energy and matter that emerge from M87's core and extend at least 5000 light-years from its centre are one of the galaxy's most mysterious and energetic features. Most matter lying close to the edge of a black hole falls in. However, some of the surrounding particles escape moments before capture and are blown far out into space in the form of jets.

Astronomers have relied on different models of how matter behaves near the black hole to better understand this process. But they still don't know exactly how jets larger than the galaxy are launched from its central region, which is as small in size as the Solar System, nor how exactly matter falls into the black hole. With the new EHT image of the black hole and its shadow in polarised light, astronomers managed for the first time to look into the region just outside the black hole where this interplay between matter flowing in and being ejected out is happening.

The observations provide new information about the structure of the magnetic fields just outside the black hole. The team found that only theoretical models featuring strongly magnetised gas can explain what they are seeing at the event horizon.

“The observations suggest that the magnetic fields at the black hole's edge are strong enough to push back on the hot gas and help it resist gravity's pull. Only the gas that slips through the field can spiral inwards to the event horizon," explains Jason Dexter, Assistant Professor at the University of Colorado Boulder, US, and coordinator of the EHT Theory Working Group.

To observe the heart of the M87 galaxy, the collaboration linked eight telescopes around the world, to create a virtual Earth-sized telescope, the EHT. The impressive resolution obtained with the EHT is equivalent to that needed to measure the length of a credit card on the surface of the Moon.

This allowed the team to directly observe the black hole shadow and the ring of light around it, with the new polarised-light image clearly showing that the ring is magnetised. The results are published today in two separate papers in The Astrophysical Journal Letters by the EHT collaboration. The research involved over 300 researchers from multiple organisations and universities worldwide.

"The EHT is making rapid advancements, with technological upgrades being done to the network and new observatories being added. We expect future EHT observations to reveal more accurately the magnetic field structure around the black hole and to tell us more about the physics of the hot gas in this region," concludes EHT collaboration member Jongho Park, an East Asian Core Observatories Association Fellow at the Academia Sinica, Institute of Astronomy and Astrophysics in Taipei.

The Event Horizon Collaboration, Kazunori Akiyama et al.: First M87 Event Horizon Telescope Results VII: polarization of the ring. Astrophysical Journal Letters, 910, L12 (2021) DOI 10.3847/2041-8213/abe71d (ApJL 910, L12)
The Event Horizon Collaboration: Kazunori Akiyama et al.: First M87 Event Horizon Telescope Results VIII: Magnetic Field Structure Near The Event Horizon. Astrophysical Journal Letters, 910, L13 (2021) DOI 10.3847/2041-8213/abe4de (ApJL 910, L13)

Pictures and Videos: (Image-Download)
A view of the M87 supermassive black hole in polarised light: The Event Horizon Telescope (EHT) collaboration, who produced the first ever image of a black hole released in 2019, has today a new view of the massive object at the centre of the Messier 87 (M87) galaxy: how it looks in polarised light. This is the first time astronomers have been able to measure polarisation, a signature of magnetic fields, this close to the edge of a black hole. This image shows the polarised view of the black hole in M87. The lines mark the orientation of polarisation, which is related to the magnetic field around the shadow of the black hole.
Credit: EHT Collaboration (Animated GIF - Download)
Observation and Theory Image: Transition animation showing the observed polarization image and a best-fit theory image. Credit: S. Issaoun, M. Mościbrodzka with Polarimetry WG and OWG (Youtube)
Zoom into the heart of galaxy M87 – The video starts with a view on the ALMA telescope which is part of the Event Horizon Telescope, and zooms into the heart of galaxy M87. In the core, the first image of a black hole can be seen, the picture was produced in 2019. Then the new image follows which shows the supermassive object in polarised light. It is the first time that astronomers could detect polarisation as a signature of magnetic fields so closely to the event horizon of a black hole. Credit: ESO/L. Calçada, Digitized Sky Survey 2, ESA/Hubble, RadioAstron, De Gasperin et al., Kim et al., EHT Collaboration. Music: Niklas Falcke (Video-Download)
Polarized Light: Light is an oscillating electromagnetic wave. If the waves have a preferred direction of oscillation, they are polarized. In space, moving hot gas, or 'plasma', threaded by a magnetic field emits polarized light.  The polarized light rays that manage to escape the pull of the black hole travel to a distant camera. The intensity of the light rays and their direction are what EHT collaboration observes with the Event Horizon Telescope.
Credit: © EHT Collaboration and Fiks Film (Youtube)
Black holes are enveloped in plasma. This plasma has magnetic fields—areas where magnetism affects how matter moves—threaded throughout. As the magnetic field grows stronger, it changes shape and the polarized light EHT collaboration measures exhibits different patterns.
Credit: © EHT Collaboration and Crazybridge Studios (Image - Download)
View of the M87 supermassive black hole and jet in polarised light. This composite image shows three views of the central region of the Messier 87 (M87) galaxy in polarised light. The galaxy has a supermassive black hole at its centre and is famous for its jets that extend far beyond the galaxy. One of the polarised-light images, obtained with the Chile-based Atacama Large Millimeter/submillimeter Array (ALMA), shows part of the jet in polarised light, with a size of 6000 light years from the centre of the galaxy. The other polarised light images zoom in closer to the supermassive black hole: the middle view covers a region about one light year in size and was obtained with the National Radio Astronomy Observatory's Very Long Baseline Array (VLBA) in the US. The most zoomed-in view was obtained by linking eight telescopes around the world to create a virtual Earth-sized telescope, the Event Horizon Telescope or EHT. This allows astronomers to see very close to the supermassive black hole, into the region where the jets are launched. The lines mark the orientation of polarisation, which is related to the magnetic field in the regions imaged. The ALMA data provides a description of the magnetic field structure along the jet. Therefore the combined information from the EHT and ALMA allows astronomers to investigate the role of magnetic fields from the vicinity of the event horizon (as probed with the EHT on light-day scales) to far beyond the M87 galaxy along its powerful jets (as probed with ALMA on scales of thousands of light-years). The values in GHz refer to the frequencies of light at which the different observations were made. The horizontal lines show the scale (in light years) of each of the individual images. Credit: EHT Collaboration; ALMA (ESO/NAOJ/NRAO), Goddi et al.; VLBA (NRAO), Kravchenko et al.; J. C. Algaba, I. Martí-Vidal

Further Information:
Prof. Dr. Luciano Rezzolla
Chair of Theoretical Astrophysics
Institute for Theoretical Physics
Goethe University Frankfurt
Phone: +49 69 798-47871 / 47879


Mar 12 2021

A research team from the universities of Frankfurt and Mainz shines a light on new global players in Africa and Asia.

How digitalisation changes cultural production around the world

When Korean pop bands such as boy group BTS reach millions of fans worldwide, and when films and music from Nigeria are seen and heard across the globe: What does this mean for the production of culture? And how does it affect our perception of cultural spaces? An interdisciplinary research team that brings together Economics, African Studies, Korean Studies, Sinology, Cultural Anthropology and Film Studies will look for answers to these questions at Goethe University Frankfurt and Johannes Gutenberg University Mainz over the next three years. With € 2.1 million in funding from Germany's Federal Ministry of Education and Research (BMBF), CEDITRAA (“Cultural Entrepreneurship and Digital Transformation in Africa and Asia") will study the emergence of what Pakistani writer Fatima Bhutto calls the “new world order of cultural production", which Hollywood and Europe no longer dominate.

FRANKFURT. In the early 1990s, Kenneth Nnebue, a Nigerian seller of home video equipment, picked up his VHS camera and changed the course of film history. To boost sales of VHS recorders, he produced his own film. “Living in Bondage" sold around 750,000 copies and spawned numerous imitations. Practically out of nowhere, Nigeria built up a film industry with global outreach, now popularly known as “Nollywood", which today ranks second only to India in terms of annual film output. “The rise of Nigeria and the global success of Korean films, TV dramas and pop music in the new millennium show that a fundamental shift is taking place in cultural production and reception across the globe," says Vinzenz Hediger, project leader and professor of cinema studies at Goethe University.

Digitalisation is one of the driving forces behind this transformation and the emergence of the “new world order of cultural production". The researchers in Frankfurt and Mainz will study how cultural industries with transregional audiences contribute to the economic growth and soft power of their regions and countries of origin. They will also examine the role of regional resources in the creative work of artists in music and film. “One open question," says economics professor Cornelia Storz, “is whether entrepreneurs in digital industries may, in fact, be more dependent on local resources than their global reach and outlook might suggest." Particular attention will be paid to how producers in music and film draw on cultural heritage to produce innovative formats which resonate with larger, global contexts.

The CEDITRAA research group will address these issues through a series of case studies on music and film in Africa and Asia. Here, the Archiv der Musik Afrikas (AMA), the Archive for the Music of Africa, at Johannes Gutenberg University Mainz will play a particularly important role. For the case studies dedicated to music and copyright issues, the AMA is an invaluable resource – particularly for research on “Afrobeats" and other forms of sub-Saharan pop music, which recombines different gernes in innovative new ways. “This music has many fans in the Global North as well," says Matthias Krings, professor of cultural anthropology and the popular culture of Africa in Mainz. “Among them is Beyoncé, who created a sensation with her 2020 album 'Black Is King', not least because it featured guest appearances by Afrobeats stars such as Burna Boy, Wizkid, Tiwa Savage and Yemi Alade."

The parts of the project dedicated to Asia will study the circulation and reception of Korean popular culture in Asia and Africa and benefit from close collaboration with non-university partners such as the Korean Film Archive. The case study dedicated to Taiwan will focus on the Kaohsiung Film Festival and its close ties to the Korean film industry. In Nigeria, the project will collaborate closely with the Nollywood Studies Centre at the Pan-Atlantic University in Lagos, a research institute with closes ties to the film and music industries in Nigeria. The Nigerian part of the project will include a PhD position at the Pan-Atlantic University.

Funded by Germany's Federal Ministry of Education and Research, the project will bring together for the first time the area studies research centres in the Rhine-Main University Alliance in a joint research initiative – the Centre for Interdisciplinary African Studies (ZIAF) and the Interdisciplinary Centre for East Asian Studies (IZO) at Goethe University and the Centre for Intercultural Studies (ZIS) at Johannes Gutenberg University Mainz.

The research project enhances the profile of area studies in the Rhine-Main University Alliance through its close connection to teaching. Project results will be used in teaching in several degree programmes, most notably the bachelor's degree programme “African Languages, Media, and Culture", which is being prepared as a joint programme of Goethe University Frankfurt and Johannes Gutenberg University Mainz.


Caption: Global popstars with an army of Twitter fans: K-pop superstars BTS (c) Kim-Hee Chu / dpa

Further information

Professor Vinzenz Hediger, Professor of Cinema Studies, Goethe University:

Professor Claudia Storz, Chair for the Study of Economic Institutions, Innovation and East Asian Development, Goethe University:

Professor Matthias Krings, Professor of Anthropology and Popular Culture of Africa, Johannes Gutenberg University Mainz:


Feb 26 2021

Clustering of receptors can have the same effect as binding a signaling molecule – receptor clusters can direct cell movement 

Cell biology: Signal transduction without signal 

Whether we smell, taste or see, or when adrenaline rushes through our veins, all of these signals are received by our cells via a specific group of receptor proteins called G protein-coupled receptors, which transmit signals to the inside of the cell. Biochemists at Goethe University Frankfurt and the University of Leipzig have now discovered that such receptors can also produce signals even in the absence of an external stimulus: It is apparently sufficient for certain receptors if many of them are clustered at the cell surface. (Science, doi/10.1126/science.abb7657)

FRANKFURT. Our body consists of 100 trillion cells that communicate with each other, receive signals from the outside world and react to them. A central role in this communication network is attributed to receiver proteins, called receptors, which are anchored at the cell membrane. There, they receive and transmit signals to the inside of the cell, where a cell reaction is triggered.

In humans, G protein-coupled receptors (GPC receptors) represent the largest group of these receptor molecules, with around 700 different types. The research of the Frankfurt and Leipzig scientists focused on a GPC receptor that serves as a receptor for the neuropeptide Y in cells and is accordingly called the Y2 receptor. Neuropeptide Y is a messenger substance that primarily mediates signals between nerve cells, which is why Y2 receptors are mainly present in nerve cells and among other activities trigger the formation of new cell connections.

In the laboratory, the researchers engineered cells, which had approx. 300,000 Y2 receptors on their surface and were grown on specifically developed, light-sensitive matrices. Each of the Y2 receptors was provided with a small molecular "label". Once the scientists created a spot of light with a fine laser beam on the cell surface, the Y2 receptor under this spot were trapped via the molecular label to the exposed matrix in such a way that the Y2 receptors moved closely together to form an assembly known as a cluster. The whole reaction could be immediately observed at the defined spot and within a few seconds.

Professor Robert Tampé from the Institute of Biochemistry at Goethe University Frankfurt explains: "The serendipity about this experiment is that the clustering of receptors triggers a signal that is similar to that of neuropeptide Y. Solely by the clustering, we were able to trigger cell movement as a reaction of the cell. The laser spots even allowed us to control the direction of the cell movement." As the light-sensitive lock-and-key pairs utilized are very small compared to the receptors, the organization of the receptors in the cell membrane can be controlled with high precision using the laser spot. "This non-invasive method is thus particularly well suited to study the effects of receptor clustering in living cells," Tampé continues. "Our method can be used to investigate exciting scientific questions, such as how receptors are organized in networks and how new circuits are formed in the brain."

Publication: M. Florencia Sánchez, Sylvia Els-Heindl, Annette G. Beck-Sickinger, Ralph Wieneke, Robert Tampé: Photo-induced receptor confinement drives ligand-independent GPCR signaling. Science abb7657
DOI: 10.1126/science.abb7657;

Image/Movie downloads:
Caption Image: Laser spots activate very small synthetic lock-and-key pairs in a matrix to create receptor clusters in the cell membrane. This ligand-independent activation triggers calcium signaling and increased cell motility. (Graphic copyright: M. Florencia Sánchez & Robert Tampé, Goethe University Frankfurt.)
Caption Movie: Upon irradiation with laser light (white rings), receptors cluster in the cell (light green circles). Thereupon, the cell moves into the direction of the receptor clusters. (Copyright: M. Florencia Sánchez & Robert Tampé, Goethe University Frankfurt). Reprinted with permission from M. F. Sánchez et al., Science 10.1126/science.abb7657(2021).

Further information:
Professor Robert Tampé
Institute of Biochemistry
Goethe-Universität Frankfurt, Germany
Phone: +49 69 798 29475


Feb 19 2021

Goethe University successful in industry open call for replacement of animal components

Search for alternatives to animal testing in toxicology research 

While many studies take place in a petri glass in toxicology research, for some processes there is still a need for animal components such as serum or liver cell tissue. A team of researchers headed by Goethe University now seeks to develop a new cell culture technique to replace the use of animal components. Their project won the “CRACK IT" innovation challenge by NC3Rs, a British organisation that works to reduce reliance on animal models in research. The challenge is sponsored by AstraZeneca and Unilever.

FRANKFURT. Studies using cell cultures are necessary in toxicology research because they make it possible to test whether new substances exhibit undesirable effects. In these studies, the serum of unborn calves (Foetal Calf Serum, FCS) is often used as animal component in the cell cultures. Other “in vitro" toxicity tests also frequently use components of animal origins. The livers of laboratory rats, for example, are used to create an enzyme cocktail that helps investigate whether liver enzymes transform the substance being tested into toxic products.

Pharma producers and companies in the cosmetic industry want to find substitutes for both components, serum and liver tissue. The reasons are not only ethical nature. Tissue and serums that are taken directly from animals also introduce inaccuracies, as their composition varies depending on origin. In addition, not all components, including those of foetal calf serum, are known. That jeopardises the reproducibility of the results. In the “CRACK IT 36: Animal-free in vitro" challenge, products of animal origin are therefore to be replaced by precisely defined and reproducible alternatives.

No more animal components in cell culture nutrient solutions

Prof. Henner Hollert und Dr. Andreas Schiwy from the Department for Evolutionary Ecology and Environmental Toxicology at Goethe University and the LOEWE Centre TBG, together with the environmental toxicologist Prof. Beate Escher from the Helmholtz Centre for Environmental Research in Leipzig (UFZ) and the companies BiodetectionsSystems in Amsterdam and Scinora in Heidelberg seek to find alternatives to these animal components.

In a first step, chemically defined nutrient solutions for cell cultures will be developed – without animal components. These nutrient solutions are already common in drug manufacturing, not least for safety reasons, as they eliminate the risk that diseases such as BSE (bovine spongiform encephalopathy) are transmitted through the calf serum.

Up to now, there have been only very few such systems for toxicological testing, because the amounts required are low in comparison with pharmaceutical production. To develop them, the metabolic processes of the cells must be known in detail.

Dispensing with laboratory rats

In a second step, the researchers want to replace the enzyme cocktail from laboratory rats by having liver cell lines metabolise the substances to be tested instead. The liver cell lines are to be grown under chemically defined culture conditions. Subsequently, the metabolic products will be extracted and their effect tested in the adapted toxicological cell cultures that were developed in the first step.

Hollert and his team will first test the process on the model substance benzo[a]pyren, a substance also found in cigarette smoke. Benzo[a]pyrene is transformed into toxic substances in the human liver, which causes damage to cell DNA and impairs hormonal balance.

Funding during the first phase amounts to 100,000 pounds, or about 114,000 euros. Following a successful evaluation, the researchers can apply in the same year for a second phase of the challenge, in which the equivalent of about 685,000 euros over another three years may be awarded.

Further information
Prof. Henner Hollert
Head of the Department for Evolutionary Ecology and Environmental Toxicology
Institute of Ecology, Evolution and Diversity
Goethe University Frankfurt
Phone: +49 69 798-42171


Feb 15 2021

Goethe University further expands scientific focus 

Newly founded: Buber-Rosenzweig Institute as a prominent research centre on modern Judaism

A new research institute will be established at Goethe University: The Buber-Rosenzweig Institute will be dedicated to the study of modern and contemporary Judaism. It brings together numerous and largely third-party funded projects and contributes further to the consolidation of this research area at Goethe University. It all began with an endowed guest professorship for Jewish philosophy of religion dedicated to Martin Buber.

FRANKFURT. The new Buber-Rosenzweig Institute is intended to provide the necessary framework for increasing visibility and focusing research energies. This requires neither state funds nor funds from the department or university: Thanks to the successful acquisition of third-party funding, especially in recent times, the foundation is on a solid financial footing. "The Executive Board has unanimously approved the founding of the Institute. We are delighted about Christian Wiese's initiative. The new institute has great potential to further expand cooperation with other institutions, especially internationally, and to initiate other important projects in the future," says Prof. Enrico Schleiff, President of Goethe University.

The origins of the institute's foundation were modest but fruitful: in 1989, the Protestant Church in Hessen and Nassau established the Martin Buber Professorship as a visiting professorship at the Department of Protestant Theology. It was intended to provide students from all disciplines, especially theology and philosophy, but also interested members of the public with an insight into the past and present of Judaism and Jewish religious philosophy. In 2005, the state of Hessen permanently took over the funding, and in 2010 the endowed guest professorship was converted into a permanent professorship. Since then, Prof. Christian Wiese has taught across disciplines in theological and religious studies subjects, but also in history and philosophy. Wiese has systematically developed the professorship into an internationally visible, third-party funded and cooperating research centre. Christian Wiese is the spokesperson for the LOEWE research hub "Religious Positioning" and one of the main applicants for the interdisciplinary Graduate School "Theology as Science". He is also the international president of the Hermann Cohen Society and vice-president of the International Franz Rosenzweig Society. His most recent success was the acquisition of funding over 24 years for the academy project "Digitization of the Buber Correspondence ".

"With its numerous externally funded projects, focus on promoting young researchers and international networking, the Martin Buber Professorship is already firmly established among research institutions on modern Jewish history and culture. The status as a research institute will open up the opportunity for us to be even more visible, to focus our activities, and to attract young international scholars," says Prof. Wiese. The very fact that the institute has limited itself to a specific period of Jewish intellectual and cultural history offers great potential: under the umbrella of an institute with such a clearly defined profile will allow further projects to arise in the future. The project "Synagogue Memorial Book of Hessen" with seven to eight staff positions is currently being developed, and further research initiatives are planned. As an institute, it will also be easier to compete with other institutions. Cooperation with the Seminar for Jewish Studies and the Fritz Bauer Institute for the History and Impact of the Holocaust within Goethe University also offers great opportunities.

The institute's name refers to the two Jewish philosophers Martin Buber (1878-1965) and Franz Rosenzweig (1886-1929), who are of great importance for the history of Goethe University. Martin Buber, who was born 143 years ago, received a teaching assignment for Jewish religion and ethics in 1924, which was initially assigned to Franz Rosenzweig; later Buber became an honorary professor. Together, Buber and Rosenzweig established the Freie Jüdische Lehrhaus in Frankfurt, a Jewish educational institution for adults. Together, the two philosophers of religion undertook a translation of the Hebrew Bible into German, which Martin Buber continued after Rosenzweig's premature death in 1929 and completed in Jerusalem in 1961. In particular after 1933, the year of Hitler’s seizure of power and Buber's withdrawal from the university, the Lehrhaus became part of the Jewish resistance against National Socialist persecution.

Further information:
Prof. Dr. Christian Wiese
Martin Buber Chair for Jewish Religious Philosophy
Faculty 06
Goethe University Frankfurt
Phone: +49 69 798-33313