Being fooled by a cosmic giant is no laughing matter for an astronomer. For years astronomers racked their brains over the relation between two in X-rays equally bright and large regions in the cluster of galaxies known as Abell 3128. ‘That is the charm of science’, says Norbert Werner, PhD student at SRON. ’You are always finding things that you did not expect.’
Clusters of galaxies are the largest structures in the universe. They consist of tens to hundreds of massive galaxies, of which each in turn consists of hundreds of billions of stars. Gravity is the binding factor. The hot gas of tens of millions degrees Celsius, present in the clusters, emits X-rays, which renders the cluster visible for space telescopes such as XMM-Newton. Detailed analyses of these X-rays tell astronomers more about the composition of the gas and accordingly, its origin.
What was so intriguing about the two X-ray spots in cluster Abell 3128 was the fact that although they had the same size and brightness, the gas clouds seemed to have completely different compositions. Werner: ‘While one spot was clearly caused by a hot gas cloud rich in metals released by supernova explosions in the galaxies, the other spot seemed to contain a much lower amount of metals than any other cluster previously observed. What we observed completely contradicted the current theories about how large structures in the universe arise.’
The observations with the XMM-Newton made the surprise complete. The gas cloud behind the puzzling X-ray spot was found to be 4.6 billion light years away, at least six times further than cluster Abell 3128. ‘We were therefore looking at two completely different objects, which from our perspective were in exactly the same line of sight’, says Norbert Werner.Foam bath
Due to their enormous mass and attractive force, the clusters have their own dynamics. Kaastra: ‘They attract each other, collide and fly through each other; a whole host of things happen that we can study with X-ray telescopes such as the XMM-Newton.’
XMM-Newton is the X-ray telescope of the European Space Agency (ESA) for which SRON built an instrument capable of analysing the X-rays in detail. XMM-Newton was launched in 1999 from French Guyana and still functions superbly. ESA recently extended the operation of the satellite for a further 5 years.
Jasper Wamsteker | alfa
From China to the South Pole: Joining forces to solve the neutrino mass puzzle
25.02.2020 | Johannes Gutenberg-Universität Mainz
Beyond the brim, Sombrero Galaxy's halo suggests turbulent past
21.02.2020 | NASA/Goddard Space Flight Center
Researchers at the University of Bayreuth have discovered an unusual material: When cooled down to two degrees Celsius, its crystal structure and electronic properties change abruptly and significantly. In this new state, the distances between iron atoms can be tailored with the help of light beams. This opens up intriguing possibilities for application in the field of information technology. The scientists have presented their discovery in the journal "Angewandte Chemie - International Edition". The new findings are the result of close cooperation with partnering facilities in Augsburg, Dresden, Hamburg, and Moscow.
The material is an unusual form of iron oxide with the formula Fe₅O₆. The researchers produced it at a pressure of 15 gigapascals in a high-pressure laboratory...
Study by Mainz physicists indicates that the next generation of neutrino experiments may well find the answer to one of the most pressing issues in neutrino physics
Among the most exciting challenges in modern physics is the identification of the neutrino mass ordering. Physicists from the Cluster of Excellence PRISMA+ at...
Fraunhofer researchers are investigating the potential of microimplants to stimulate nerve cells and treat chronic conditions like asthma, diabetes, or Parkinson’s disease. Find out what makes this form of treatment so appealing and which challenges the researchers still have to master.
A study by the Robert Koch Institute has found that one in four women will suffer from weak bladders at some point in their lives. Treatments of this condition...
The operational speed of semiconductors in various electronic and optoelectronic devices is limited to several gigahertz (a billion oscillations per second). This constrains the upper limit of the operational speed of computing. Now researchers from the Max Planck Institute for the Structure and Dynamics of Matter in Hamburg, Germany, and the Indian Institute of Technology in Bombay have explained how these processes can be sped up through the use of light waves and defected solid materials.
Light waves perform several hundred trillion oscillations per second. Hence, it is natural to envision employing light oscillations to drive the electronic...
Most natural and artificial surfaces are rough: metals and even glasses that appear smooth to the naked eye can look like jagged mountain ranges under the microscope. There is currently no uniform theory about the origin of this roughness despite it being observed on all scales, from the atomic to the tectonic. Scientists suspect that the rough surface is formed by irreversible plastic deformation that occurs in many processes of mechanical machining of components such as milling.
Prof. Dr. Lars Pastewka from the Simulation group at the Department of Microsystems Engineering at the University of Freiburg and his team have simulated such...
12.02.2020 | Event News
16.01.2020 | Event News
15.01.2020 | Event News
25.02.2020 | Power and Electrical Engineering
25.02.2020 | Earth Sciences
25.02.2020 | Life Sciences