X-ray scout sees first light

October 25, 2019

Astronomers are excited: the first images of the eRosita telescope launched in July reveal an impressive performance. After an extended commissioning phase, all seven X-ray telescope modules with their custom-designed CCD cameras have been observing the sky simultaneously since 13 October. The first composite images show our neighbouring galaxy, the Large Magellanic Cloud, and two interacting clusters of galaxies at a distance of about 800 million light years in remarkable detail.

"Now we can start reaping the fruits of more than ten years of work. We are all impressed by the beautiful first images from our telescope," enthuses Peter Predehl, Principal Investigator of eROSITA. "To meet our science goals we needed enough sensitivity to detect the most distant clusters of galaxies in the X-ray Universe over the whole sky, and resolve them spatially. These First Light images show that we can do exactly that, but we can go a lot further. The CCD cameras are state-of the art with superb spectral and timing resolution. The potential for new discoveries is immense." The eROSITA First Light images were obtained in a series of exposures of all seven telescope modules with a combined integration time of about one day for both the Large Magellanic Cloud (LMC), our neighbouring galaxy, and the A3391/3395 system of interacting clusters of galaxies at a distance of about 800 Million lightyears.

In our neighbouring galaxy, the LMC, eROSITA not only shows the distribution of the LMCs diffuse hot gas, but also some remarkable details, such as supernova remnants like SN1987A. The eROSITA image now confirms that this source is becoming fainter, as the shock wave produced in by the stellar explosion in 1987 propagates through the interstellar medium. In addition to a host of other hot objects in the LMC itself, eROSITA also reveals a number of foreground stars from our own Milky Way galaxy as well as distant Active Galactic Nuclei, whose radiation pierces the diffuse emission of the hot gas in the LMC.

"X-rays give us a unique view of the Universe", explains Kirpal Nandra, director of high energy astrophysics at MPE. "Looking at an apparently normal star, we might see an orbiting white dwarf or neutron star in the process of devouring its companion. Visible light shows the structure of a galaxy traced by its stars, but the X-rays are dominated by supermassive black holes growing at their centres. And where we see clusters of galaxies with optical telescopes, X-rays reveal the huge reservoirs of gas filling the space between them and tracing out the dark matter structure of the Universe. With its performance demonstrated, we now know that eROSITA will lead to a breakthrough in our understanding of the evolution of the energetic Universe."

Reaching further out into the Universe, the eROSITA image of the A3391/3395 system of interacting clusters of galaxies highlights the dynamical processes which lead to the formation of gigantic structures in the Universe. The clusters, appearing as large, elliptical nebulae in the eROSITA images, span tens of millions of lightyears across, and contain thousands of galaxies each. Clusters of galaxies are one of the main science targets for eROSITA; astronomers expect to find some 100,000 X-ray emitting galaxy clusters as well as several million active black holes in the centres of galaxies during its 4-year all-sky survey in the soft and hard X-ray bands.

"This is a dream come true. We now know that eROSITA can deliver on its promise and create a map of the whole X-ray sky with unprecedented depth and detail," confirms Andrea Merloni, eROSITA Project Scientist. "The legacy value will be enormous. Beside the beautiful images like the ones we're showing today, catalogues of millions of exotic celestial objects such as black holes, galaxy clusters, neutron stars, supernovae and active stars will be used by astronomers for years to come."

Launched on 13 July 2019 as part of the Russian-German Spektrum-Roentgen-Gamma (SRG) space mission, which also includes the Russian ART-XC telescope, eROSITA completed its 1.5 million kilometre journey to the second Lagrange point (L2) of the Earth-Sun-system in late September and has now - 100 days after launch - entered an orbit around L2. The commissioning phase of the telescope was officially completed on 13 October. While the scientific performance of the system is outstanding, this first phase was not problem-free.

"The commissioning phase lasted longer than expected, after we found some anomalies in the electronic controls of the cameras," explains Peter Predehl. "But teasing out these problems is exactly why we have such a phase. After a careful analysis we determined that the issues are not critical. We're still working on them, but in the meantime the programme can go forward normally." The telescope has now entered the so-called calibration and performance verification (CalPV) phase, during which astronomical observations are carried out to better understand the instrument and verify its full potential to meet the scientific requirements. At the end of the CalPV phase, after a final review by the operations team, SRG and eROSITA will enter into its prime phase, the four year all-sky X-ray survey.
The development and construction of the eROSITA X-ray telescope was led by the Max Planck Institute for Extraterrestrial Physics with contributions from the Institute for Astronomy and Astrophysics of the University Tübingen, the Leibniz Institute for Astrophysics Potsdam (AIP), University Observatory Hamburg, and Dr. Karl Remeis Observatory Bamberg, with the support of the German space agency DLR. The Ludwig-Maximilians-Universität Munich and the Argelander Institute for Astronomy of the University Bonn also participate in science preparation for eROSITA. The Russian partner Institute is the Space Research Institute IKI in Moskau; NPOL, Lavochkin Association, Khimky near Moskau, is responsible for the technical implementation of the whole SRG mission, which is a joint project of the Russian and German space agencies, Roscosmos and DLR.


Related Black Holes Articles from Brightsurf:

The black hole always chirps twice: New clues deciphering the shape of black holes
A team of gravitational-wave scientists led by the ARC Centre of Excellence for Gravitational Wave Discovery (OzGrav) reveal that when two black holes collide and merge, the remnant black hole 'chirps' not once, but multiple times, emitting gravitational waves--intense ripples in the fabric space and time--that inform us about its shape.

Black holes? They are like a hologram
Spherical, smooth and simple according to the theory of relativity, or extremely complex and full of information as, according to quantum laws, Stephen Hawking used to say?

Under pressure, black holes feast
A new, Yale-led study shows that some supermassive black holes actually thrive under pressure.

Staining cycles with black holes
In the treatment of tumors, microenvironment plays an important role.

Black holes sometimes behave like conventional quantum systems
A group of Skoltech researchers led by Professor Anatoly Dymarsky have studied the emergence of generalized thermal ensembles in quantum systems with additional symmetries.

Scientists may have discovered whole new class of black holes
New research shows that astronomers' search for black holes might have been missing an entire class of black holes that they didn't know existed.

Are black holes made of dark energy?
Two University of Hawaii at Manoa researchers have identified and corrected a subtle error that was made when applying Einstein's equations to model the growth of the universe.

Telescopes in space for even sharper images of black holes
Astronomers have just managed to take the first image of a black hole, and now the next challenge facing them is how to take even sharper images, so that Einstein's Theory of General Relativity can be tested.

Can entangled qubits be used to probe black holes?
Information escapes from black holes via Hawking radiation, so it should be possible to capture it and use it to reconstruct what fell in: if given time longer than the age of the universe.

How black holes power plasma jets
Cosmic robbery powers the jets streaming from a black hole, new simulations reveal.

Read More: Black Holes News and Black Holes Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.