Astronomers challenge 50-year-old quasar law

An artist’s impression of a bright quasar almost outshining its host galaxy. Credit: Dimitrios Sakkas (tomakti), Antonis Georgakakis, Angel Ruiz, Maria Chira (NOA)

Licence type: Attribution (CC BY 4.0)

Compelling evidence that the structure of matter surrounding supermassive black holes has changed over cosmic time has been uncovered by an international team of astronomers. If true, the research led by the National Observatory of Athens and published today in Monthly Notices of the Royal Astronomical Society would challenge a fundamental law which has existed for almost five decades.

Quasars – first identified in the 1960s – are some of the brightest objects in the universe. They are powered by supermassive black holes as matter, pulled by strong gravity, spirals inwards, forming a rotating disc-like structure which eventually plunges into the black hole.

This disc is extremely hot because of the friction between matter particles as they revolve around the black hole. It produces 100 to 1,000 times as much light as an entire galaxy containing 100 billion stars, generating a glow that outshines its host galaxy and everything in it. This vast amount of ultraviolet light can be observed by telescopes, allowing astronomers to find quasars at the edge of the universe.

The ultraviolet light of the disc is also believed to be the fuel for the much more energetic X-ray light produced by quasars: the ultraviolet light rays as they travel through space intercept clouds of highly energetic particles very close to the black hole, a structure also known as the “corona”.

As they bounce off these energetic particles, the ultraviolet rays are boosted in energy and generate intense X-ray light that our detectors can also spot.

eROSITA real image of a region of the X-ray sky centered at one of the quasars used in the new research. Credit: Angel Ruiz (NOA) based on maps created by Jeremy Sanders (MPE)

Licence type: Attribution (CC BY 4.0)

Because of their shared history, the X-ray and ultraviolet emissions of quasars are tightly connected – brighter ultraviolet light typically means stronger X-ray intensity. This correlation, discovered nearly 50 years ago, provides fundamental insights into the geometry and physical conditions of the material close to supermassive black holes and has been the focus of intense research for decades.

The latest research adds a new twist to previous studies by challenging the universality of the correlation – a fundamental assumption that implies that the structure of matter around black holes is similar throughout the universe.

It shows that when the universe was younger – about half its present age – the correlation between the X-ray and ultraviolet light of quasars was significantly different from that observed in the nearby universe. The discovery suggests that the physical processes linking the accretion disc and the corona around supermassive black holes may have changed over the last 6.5 billions of years of cosmic history.

“Confirming a non-universal X-ray-to-ultraviolet relation with cosmic time is quite surprising and challenges our understanding of how supermassive black holes grow and radiate,” said Dr Antonis Georgakakis, one of the study’s authors.

“We tested the result using different approaches, but it appears to be persistent.”

The study combines new X-ray observations from eROSITA X-ray telescope and archival data from the XMM-Newton X-ray observatory of the European Space Agency to explore the relation between X-ray and ultraviolet light intensity of an unprecedentedly large sample of quasars. The new eROSITA’s wide and uniform X-ray coverage proved decisive, enabling the team to study quasar populations on a scale never before possible.

An artist’s impression of matter spiralling inwards, pulled by the strong gravity of a central supermassive black hole, forming an “accretion disk”. Friction heats the infalling material to high temperatures producing intense ultraviolet light. This is reprocessed by hot plasma (extremely high temperature matter) believed to exist very close to the black hole — the “corona” — to produce energetic X-ray light. Credit: Dimitrios Sakkas (tomakti), Antonis Georgakakis, Angel Ruiz, Maria Chira (NOA)

Licence type: Attribution (CC BY 4.0)

The universality of the UV-to-X-ray relation underpins certain methods that use quasars as "standard candles" to measure the geometry of the universe and ultimately probe the nature of dark matter and dark energy. This new result highlights the necessity for caution, demonstrating that the assumption of unchanging black hole structure across cosmic time must be rigorously re-examined.

“The key advance here is methodological,” said postdoctoral researcher Maria Chira, of the National Observatory of Athens, who is the paper’s lead author.

“The eROSITA survey is vast but relatively shallow – many quasars are detected with only a few X-ray photons. By combining these data in a robust Bayesian statistical framework, we could uncover subtle trends that would otherwise remain hidden.”

The full set of eROSITA all-sky scans will soon allow astronomers to probe even fainter and more distant quasars. Future analyses using these data – together with next-generation X-ray and multiwavelength surveys – will help reveal whether the observed evolution reflects a genuine physical change or simply selection effects.

Such studies will bring new insight into how supermassive black holes power the most luminous objects in the universe, and how their behaviour has evolved over cosmic time.

Source: Royal Astronomical Society (RAS)/Research Highlights

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Media contacts:

Sam Tonkin
Royal Astronomical Society
Mob: +44 (0)7802 877 700
press@ras.ac.uk

Dr Robert Massey
Royal Astronomical Society
Mob: +44 (0)7802 877 699
press@ras.ac.uk

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Science contacts:

Maria Chira
National Observatory of Athens
mchira@noa.gr

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Further information

The paper ‘Revisiting the X-ray–to–UV relation of Quasars in the era of all-sky surveys’ by Maria Chira et al. has been published in Monthly Notices of the Royal Astronomical Society. DOI: 10.1093/mnras/staf1551.

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Notes for editors

About the Royal Astronomical Society

The Royal Astronomical Society (RAS), founded in 1820, encourages and promotes the study of astronomy, solar-system science, geophysics and closely related branches of science.

The RAS organises scientific meetings, publishes international research and review journals, recognises outstanding achievements by the award of medals and prizes, maintains an extensive library, supports education through grants and outreach activities and represents UK astronomy nationally and internationally. Its more than 4,000 members (Fellows), a third based overseas, include scientific researchers in universities, observatories and laboratories as well as historians of astronomy and others.

The RAS accepts papers for its journals based on the principle of peer review, in which fellow experts on the editorial boards accept the paper as worth considering. The Society issues press releases based on a similar principle, but the organisations and scientists concerned have overall responsibility for their content.

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Submitted by Sam Tonkin on Thu, 11/12/2025 - 08:00

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Serendipitous detection of a rapidly accreting black hole in the early Universe

A new, faint X-ray source (right) was found in the eROSITA Final Equatorial-Depth Survey (eFEDS). Using optical follow-up observations (left top), the eROSITA team identified this as a quasar at a redshift of z=6.56. Quasars are powered by a central supermassive black hole, accreting material at a high rate. This is the most distant blind X-ray detection to date and allows the scientists to investigate the growth of black holes in the early Universe. Credit: Collage: MPE/Cluster Origins

X-ray image cutouts in the region of J0921+0007. The eROSITA/eFEDS image is on the left, the high-resolution Chandra image is on the right. Credit: © MPE

eROSITA telescope finds an X-ray bright, optically faint quasar accreting material at an extremely high rate only about 800 million years after the big bang

Analysing data from the eROSITA Final Equatorial-Depth Survey, astronomers at MPE have found a faint X-ray source identified with a very distant supermassive black hole that is accreting material at an extremely high rate. This quasar, at a redshift of z=6.56, is much more luminous in X-rays than expected. This is the most distant blind X-ray detection to date, from an object whose radiation was emitted almost 13 billion years ago and allows the scientists to investigate the growth of black holes in the early Universe.

Supermassive black holes at the centres of galaxies can be detected out to great distances – but only if they accrete matter, which heats up and shines brightly, causing it to become an “active galactic nucleus” (AGN). These “quasars” or quasi-stellar objects then outshine the rest of their galaxy, but at large distances, they nevertheless are difficult to detect and extremely rare. To date, only about 50 quasars with redshift z>5.7, when the Universe was less than one billion years old, have been detected in X-rays.

Analysing X-ray data of the eROSITA Final Equatorial-Depth Survey (eFEDS), which were taken during the Performance Verification Phase of the eROSITA telescope in 2019, the eROSITA team found a new point source. In collaboration with colleagues using the Subaru telescope, they identified the X-ray emission with a previously known quasar J0921+0007 at a redshift of 6.56, which was initially discovered by a team searching for distant sources with the Subaru telescope. Dedicated follow-up observations at infrared wavelengths showed that the black hole has 250 million solar masses, a relatively low mass for a supermassive black hole at this distance. Chandra follow-up observations confirmed the high X-ray luminosity measured by eROSITA, indicating a very high accretion rate.

“We did not expect to find such a low-mass AGN already in our very first mini-survey with eROSITA”, says Julien Wolf, who searches for the most distant supermassive black holes in eROSITA data as part of his Ph.D. at the Max Planck Institute for Extraterrestrial Physics (MPE). “It is the most distant serendipitous X-ray detection to date and its properties are rather atypical for quasars at such high redshifts: it is intrinsically faint in visible light but very luminous in X-rays.”

The quasar detected by eROSITA shows properties, which are similar to so-called narrow-line Seyfert-1 galaxies, a particular class of active galaxies in the local Universe. They are associated with supermassive black holes below 100 million solar masses, accreting matter at a high rate, and could be younger than their higher mass siblings.

“Hunting for rare objects like this needs deep multi-wavelength data complementing the large X-ray survey area. Luckily, most of the sky is mapped at optical and infrared wavelengths, although the Subaru data in eFEDS area are especially deep,” emphasises Mara Salvato, eROSITA spokesperson.

While the bulk of active galaxies detected at high redshifts (i.e. large distances) host black holes with masses of one to ten billion solar masses, there must also be many with less massive black holes. These, however, need to accrete matter at a very high rate to shine brightly enough so that they can be detected at all.

In addition to this source, the team had earlier found another luminous and similarly distant quasar in the same field. “eROSITA is uniquely suited to performing a census of rare X-ray objects like these powerful high-redshift quasars,” states Kirpal Nandra, director of high-energy physics at MPE. “This is now the second example we’ve found in eFEDS when we expected to find none”.

The early eROSITA data are just a foretaste of what’s to come. Based on these early detections, the scientists expect to find hundreds more examples with the eROSITA all-sky survey. In an effort to find this elusive population of yet unknown distant quasars, the group has developed a large programme exploring the eROSITA all-sky survey. This dedicated survey has already led to the discovery of five new X-ray luminous quasars at z>5.6, which will be presented in a future publication. Simultaneously, a Russian team of researchers have also reported the first eROSITA high-redshift detections in the northern hemisphere.

Objects like these are currently our best way of understanding early black hole formation. If the surprising eFEDS detections are confirmed in the larger dataset, it could represent a challenge for some evolutionary models.

Contacts:

Julien Wolf
phd student
tel.+49 89 30000-3879
fax.+49 89 30000-3569
jwolf@mpe.mpg.de

Mara Salvato
Senior Scientist
tel.+49 89 30000-3815
fax.+49 89 30000-3569
mara@mpe.mpg.de

Kirpal Nandra
director
tel.+49 89 30000-3401
fax.+49 89 30000-3569
knandra@mpe.mpg.de

Original publication

J. Wolf, K. Nandra, M. Salvato, et al.
X-ray emission from a rapidly accreting narrow-line Seyfert 1 galaxy at z=6.56 A&A 669, A127 (2023)
Source

Source: Max Planck Institute for Extraterrestrial Physics

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Star on a dangerous path provides regular meals for supermassive black hole

The light-curve of the new source, J0456-20, shows four distinctive phases: The X-ray flux plateau phase lasts about two months and then drops rapidly (by a factor of 100) within one week. A faint X-ray stage follows this for about 2-3 months before it starts the X-ray rising phase again. The whole cycle lasts about 220 days. © MPE

This sketch shows the sequence of events that could explain the evolution of the light curve in J0456-20: A star is partially disrupted when coming close to a supermassive black hole (top). The stellar debris forms an accretion disk (blue), with the accretion proceeding in various stages (1-5) with changing emission signatures. Eventually, the fuel is completely exhausted (6) and no more X-ray flares will be detected. © MPE

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eROSITA all-sky survey detects repeating X-ray flares in an otherwise quiescent galaxy.

In the eROSITA all-sky survey, scientists at the Max Planck Institute for Extraterrestrial Physics (MPE) have found an interesting repeating event. In an otherwise quiescent galaxy, an X-ray flare repeats every 220 days, indicating that a star orbiting the central black hole “feeds” the gravity monster on subsequent orbits. Such events could be effective tools to explore the accretion process and the gravity field around supermassive black holes in other galaxies.

Most galaxies harbour a supermassive black hole at their centre, and observations suggest a symbiotic growth of the central black hole and the host galaxy. These studies mainly concentrate on ‘active’ galaxies, i.e., those where the central black hole persistently accretes large amounts of matter, which heats up and shines very brightly. However, these active galaxies (or active galactic nuclei, AGN) are vastly outnumbered by quiescent galaxies, in which it is much harder to infer the presence of the nuclear supermassive black hole.

Occasionally, a star might wander too close to the central black hole in a galaxy and be disrupted by its strong tidal forces, in a so called „tidal disruption event“. These events result in the star losing its material to the black hole, temporarily increasing the fuelling rate of the gravity monster, and producing an X-ray flare as the stellar matter is consumed. Occurring roughly once every 10000 years per galaxy, tidal disruption events are rare, and most observed candidates to-date are one-off events that show only a single flare due to the destruction of the star. Recently, a few transients have been reported that show periodic or repeating flares. These could be due to stars that are fortunate to survive their first encounter. Instead of being disrupted completely, the remnant orbits the supermassive black hole, losing parts of its outer layers and fuelling the black hole with each passage.

Such repeating partial disruption events could be effective tools to explore the accretion process around supermassive black holes”, points out Zhu Liu, the lead author of the study at MPE. “With eROSITA we found a very intriguing repeating nuclear transient in an otherwise quiescent galaxy.”

During its all-sky survey, the eROSITA X-ray telescope observed every position on the sky multiple times, thereby uncovering high-energy transients in galaxies that showed no signatures of prior activity at their centres. The new source, J0456-20, discovered in February 2021, is located in a quiescent galaxy about 1 billion light-years away. It is one of the most variable X-ray sources seen by eROSITA, with the X-ray flux dropping by a factor of 100 within a week. In total, the astronomers observed three complete cycles of repeating X-ray flares from the source, with a recurrence time of around 220 days. Follow-up optical observations showed a typical quiescent galaxy, while the repeating X-ray flares strongly suggest a repeating partial tidal disruption event.

“We estimate that the star orbiting the black hole lost the equivalent of 5%, 1.5% and 0.5% of the mass of our Sun in its first, second, and third visit, respectively”, explains Adam Malyali, a postdoc at MPE. “These losses are small enough that the star could survive several partial disruption episodes.”

Through a collaboration with the Australian ATCA facility, the scientists also discovered transient radio emission from J0456-20, indicating the launch of an outflow of gas or a jet. Together with the characteristic X-ray evolution, there is compelling evidence for changes in the structure of the accretion disk around the supermassive black hole. “More follow-up observations are needed to pin down the exact details of the physical processes,” says Andrea Merloni, eROSITA principal investigator. “Nevertheless, the discovery of this repeating X-ray event already provides solid evidence that there are stars in tightly bound orbits around supermassive black holes beyond our own Milky Way galaxy. These offer ideal laboratories to test General Relativity in the strong field regime.”

eROSITA has already found other repeating X-ray sources, e.g. two quasi-periodic eruptions in AGN. In the future, the scientists expect to discover more events with eROSITA, and the upcoming Einstein Probe mission.

Source: Max Planck Institute for Extraterrestrial Physics (MPE)

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Contacts:

Zhu Liu
postdoc
tel.+49 89 30000-3855
fax.+49 89 30000-3569
liuzhu@mpe.mpg.de

Adam Malyali
postdoc
tel.+49 89 30000-3644
fax.+49 89 30000-3644
amalyali@mpe.mpg.de

Andrea Merloni
Senior Scientist
tel.+49 89 30000-3893
fax.+49 89 30000-3569
am@mpe.mpg.de
Original publication:

Zhu Liu, A. Malyali, M. Krumpe et al.
Deciphering the extreme X-ray variability of the nuclear transient eRASSt J045650.3 A&A, 669, A75
Source / DOI

More Information

eROSITA
eROSITA webpages at MPE

XMM-Newton spies black holes eating the same stars again and again
ESA Press Release

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Our deepest view of the X-ray sky

The energetic universe as seen with the eROSITA X-ray telescope. The first eROSITA all-sky survey was conducted over a period of six months by letting the telescope rotate continuously, thus providing a uniform exposure of about 150-200 seconds over most of the sky, with the ecliptic poles being visited more deeply. As eROSITA scans the sky, the energy of the collected photons is measured with an accuracy ranging from 2% - 6%. To generate this image, in which the whole sky is projected onto an ellipse (so-called Aitoff projection) with the centre of the Milky Way in the middle and the body of the Galaxy running horizontally, photons have been colour-coded according to their energy (red for energies 0.3-0.6 keV, green for 0.6-1 keV, blue for 1-2.3 keV). The original image, with a resolution of about 10”, and a corresponding dynamic range of more than one billion, is then smoothed (with a 10’ FWHM Gaussian) in order to generate the above picture.The red diffuse glow away from the galactic plane is the emission of the hot gas in the vicinity of the solar system (the Local Bubble). Along the plane itself, dust and gas absorb the lowest energy X-ray photons, so that only high-energy emitting sources can be seen, and their colour appears blue in the image. The hotter gas close to the galactic centre, shown in green and yellow, carries imprinted the history of the most energetic processes in the life of the Milky Way, such as supernova explosions, driving fountains of gas out of the plane, and, possibly, past outburst from the now dormant supermassive black hole in the centre of the galaxy. Piercing through this turbulent, hot diffuse medium, are hundreds of thousands of X-ray sources, which appear mostly white in the image, and uniformly distributed over the sky. Among them, distant active galactic nuclei (including a few emitting at a time when the Universe was less than one tenth of its current age) are visible as point sources, while clusters of galaxies reveal themselves as extended X-ray nebulosities. In total, about one million X-ray sources have been detected in the eROSITA all-sky image, a treasure trove that will keep the teams busy for the coming years. Credit: Jeremy Sanders, Hermann Brunner and the eSASS team (MPE); Eugene Churazov, Marat Gilfanov (on behalf of IKI). Additional Images

The eROSITA telescope has provided a new, sharp view of hot and energetic processes across the Universe

Over the course of 182 days, the eROSITA X-ray telescope onboard SRG has completed its first full sweep of the sky. This new map of the hot, energetic universe contains more than one million objects, roughly doubling the number of known X-ray sources discovered over the 60-year history of X-ray astronomy. Most of the new sources are active galactic nuclei at cosmological distances, marking the growth of gigantic black holes over cosmic time. Clusters of galaxies in the new map will be used to track the growth of cosmic structures and constrain cosmological parameters. Closer to home, stars with hot coronae, binaries and supernova remnants dot our Galaxy, and we now have a complete map of the hot baryons in the Milky Way, something that can only be achieved with the 360-degree view provided by the eROSITA survey.

A million X-ray sources revealing the nature of the hot universe – this is the impressive harvest of the first scan of the entire sky with the eROSITA telescope onboard SRG. “This all-sky image completely changes the way we look at the energetic universe,” says Peter Predehl, the Principal Investigator of eROSITA at the Max Planck Institute for Extraterrestrial Physics (MPE). “We see such a wealth of detail - the beauty of the images is really stunning.”

This first complete sky image from eROSITA is about 4 times deeper than the previous all-sky survey by the ROSAT telescope 30 years ago, and has yielded around 10 times more sources: about as many as have been discovered by all past X-ray telescopes combined. And while most classes of astronomical objects emit in X-rays, the hot and energetic Universe looks quite different to the one seen by optical or radio telescopes. Looking outside the body of our Galaxy, most of the eROSITA sources are active galactic nuclei, accreting supermassive black holes at cosmological distances, interspersed with clusters of galaxies, which appear as extended X-ray haloes shining thanks to the hot gas confined by their huge concentrations of dark matter. The all-sky image reveals in exquisite detail the structure of the hot gas in the Milky Way itself, and the circum-galactic medium, which surrounds it, whose properties are key to understanding the formation history of our Galaxy. The eROSITA X-ray map also reveals stars with strong, magnetically active hot coronae, X-ray binary stars containing neutron stars, black holes or white dwarves, and spectacular supernova remnants in our own and other nearby galaxies such as the Magellanic clouds.

Due to its size and close distance to Earth, the "Vela supernova remnant" which is shown in this picture is one of the most prominent objects in the X-ray sky. The Vela supernova exploded about 12000 years ago at a distance of 800 light-years and overlaps with at least two other supernova remnants, Vela Junior (in the picture seen as bluish ring at the bottom left) and Puppis-A (top right). Vela Junior was discovered just 20 years ago, although this object is so close to Earth that remains of this explosion were found in polar ice cores. All three supernova explosions produced both the X-ray-bright supernova remnants and neutron stars, which shine as intense X-ray point sources near the centres of the remnants. The quality of the new eROSITA data of this "stellar cemetery" will give astronomers many exciting new insights into the physical processes operating in the hot supernova plasma as well as for exploring the exotic neutron stars. Credit: Peter Predehl, Werner Becker (MPE), Davide Mella

We were all eagerly awaiting the first all-sky map from eROSITA,” says Mara Salvato, the scientist at MPE who leads the effort to combine eROSITA observations with other telescopes across the electromagnetic spectrum. “Large sky areas have already been covered at many other wavelengths, and now we have the X-ray data to match. We need these other surveys to identify the X-ray sources and understand their nature.” The survey is also a treasure trove of rare and exotic phenomena, including numerous types of transients and variables, such as flares from compact objects, merging neutron stars, and stars being swallowed by black holes. “eROSITA often sees unexpected bursts of X-rays from the sky,” continues Salvato. “We need to alert ground-based telescopes immediately to understand what’s producing them.”  

Assembling the image has been a mammoth task. So far, the operations team has received and processed about 165 GB of data collected by eROSITA’s seven cameras. While relatively small by “big-data” standards on the ground, operating this complex instrument in space provided its own special challenges. “We check and monitor the health of the instrument on a daily basis, in cooperation with our colleagues in Moscow who operate the SRG spacecraft” explains Miriam Ramos-Ceja, a member of the eROSITA operations team at MPE. “This means we can respond quickly to any anomalies. We’ve been able to react to these immediately to keep the instrument safe, while collecting data at ~97% efficiency. It’s amazing to be able to communicate in real time with an instrument located 1.5 million kilometres away!” The data downlink occurs daily. “We perform immediate quality checks on the data”, she continues, “before it is being processed and analysed by the teams in Germany and Russia.”

While the team is now busy analysing this first all-sky map and using the images and catalogues to deepen our understanding of cosmology and high-energy astrophysical processes, the telescope continues its sweep of the X-ray sky. “The SRG Observatory is now starting its second all-sky survey, which will be completed by the end of this year“, says Rashid Sunyaev, Lead Scientist of the Russian SRG team. “Overall, during the next 3.5 years, we plan to get 7 maps similar to the one seen in this beautiful image. Their combined sensitivity will be a factor of 5 better and will be used by astrophysicists and cosmologists for decades.“

Kirpal Nandra, head of the high-energy astrophysics group at MPE, adds “With a million sources in just six months, eROSITA has already revolutionized X-ray astronomy, but this is just a taste of what’s to come. This combination of sky area and depth is transformational. We are already sampling a cosmological volume of the hot Universe much larger than has been possible before. Over the next few years, we’ll be able to probe even further, out to where the first giant cosmic structures and supermassive black holes were forming.”

The Shapley supercluster of galaxies is one of the most massive concentrations of galaxies in the local universe at a distance of about 650 million light-years (z~0.05). Each of the dozen extended structures is itself a cluster of galaxies, consisting of 100s to 1000s of individual galaxies, each denoting an intersection of filaments making up the large-scale structure in the Universe. This image spans 16 degrees across the sky (about 30 times the size of the full moon), which translates into about 180 million light-years across at the distance of the Shapley supercluster. The images on the left show a zoom of the the most massive clusters in the Shapley supercluster.  Credit: Esra Bulbul, Jeremy Sanders (MPE)

Further information:

On 11 June 2020, the eROSITA telescope completed its first survey of the entire X-ray sky. Launched on 13 July 2019 on-board the SRG spacecraft and now orbiting the second Lagrange point of the Earth-Sun-system, the telescope is in continuous scanning mode. During the first all-sky survey, each point in the sky was exposed to the eROSITA telescope for an average duration of 150-200 seconds. The regions close to the ecliptic poles, where the great circles traced by the telescope on the sky intersect, were revisited many times, accumulating exposures of up to a few hours. SRG will continue scanning the sky for three and half years more, with eROSITA performing seven more all-sky surveys in the process.

eROSITA is the primary instrument aboard SRG, a joint Russian-German science mission supported by the Russian Space Agency (Roskosmos), in the interests of the Russian Academy of Sciences represented by its Space Research Institute (IKI), and the Deutsches Zentrum für Luft- und Raumfahrt (DLR). The SRG spacecraft was built by Lavochkin Association (NPOL) and its subcontractors, and is operated by NPOL with support from the Max-Planck Institute for Extraterrestrial Physics (MPE).

The development and construction of the eROSITA X-ray instrument was led by the Max Planck Institute for Extraterrestrial Physics (MPE), with contributions from the Dr. Karl Remeis Observatory Bamberg, the University of Hamburg Observatory, the Leibniz Institute for Astrophysics Potsdam (AIP), and the Institute for Astronomy and Astrophysics of the University of Tübingen, with the support of DLR and the Max Planck Society. The Argelander Institute for Astronomy of the University of Bonn and the Ludwig-Maximilians-Universität Munich also participated in the science preparation for eROSITA.

The eROSITA data shown here were processed using the eSASS software system developed by the German eROSITA consortium.

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Contacts

Dr. Andrea Merloni
Senior Scientist
+49 (0)89 30000-3893
+49 (0)89 30000-3569

Dr. Peter Predehl
Senior Scientist
+49 (0)89 30000-3505
+4915112113639
+49 (0)89 30000-3569

Prof. Dr. Kirpal Nandra
director
+49 (0)89 30000-3401

+49 (0)89 30000-3569

Source:  Max Planck Institute for Extraterrestrial Physics

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