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‘Survivor’ Black Holes May Be Mid-Sized

Copyright X-ray: NASA/ CXC/Tsinghua Univ./H. Feng et al.

New evidence from NASA’s Chandra X-ray Observatory and ESA’s XMM-Newton strengthens the case that two mid-sized black holes exist close to the center of a nearby starburst galaxy. These “survivor” black holes avoided falling into the center of the galaxy and could be examples of the seeds required for the growth of supermassive black holes in galaxies, including the one in the Milky Way.

For several decades, scientists have had strong evidence for two distinct classes of black hole: the stellar-mass variety with masses about ten times that of the Sun, and the supermassive ones, located at the center of galaxies, that range from hundreds of thousands to billions of solar masses.

But a mystery has remained: what about black holes that are in between? Evidence for these objects has remained controversial, and until now there were no strong claims of more than one such black hole in a single galaxy. Recently, a team of researchers has found signatures in X-ray data of two mid-sized black holes in the starburst galaxy M82 located 12 million light years from Earth.

“This is the first time that good evidence for two mid-sized black [...]

Faster, cheaper chips from space technology

Faster, cheaper chips from space technology

Copyright ESA

Our world is full of integrated semiconductor circuits, commonly known as microchips. Today you find them in computers, cars, mobile phones and in almost every electrical device. Technology from ESA’s XMM-Newton space telescope will make these chips much smaller, faster and cheaper.

The demand for faster and more powerful chips requires the use of extreme ultraviolet (EUV). Much smaller semiconductor circuits can be produced, leading to microchips up to 100 times faster and to memory chips with up to 100 times more storage capacity. However, conventional lenses cannot focus EUV rays. Instead, special ‘grazing-incidence mirrors’ must be used, and it is here that space technology comes in.

Italian company Media Lario Technologies has developed grazing-incidence mirrors to make chips by extending the technology originally used for producing the advanced telescope mirrors for Europe’s XMM-Newton X-ray observatory.

Space telescope produced by highly accurate electroforming technology

Since 1999, XMM-Newton’s telescope has been delivering stunning X-ray images of our Universe.

This is above all due to its exceptional mirrors – the most sensitive ever developed – which total 200 sq m covered by ultra-smooth gold. Statistically, no gold atoms stick out from the surface by more than their [...]

XMM-Newton discovers a new class of black holes

XMM-Newton discovers a new class of black holes

Copyright ESA

Astronomers using ESA’s XMM-Newton X-ray observatory have discovered a black hole weighing more than 500 solar masses, a missing link between lighter stellar-mass and heavier supermassive black holes, in a distant galaxy. This discovery is the best detection to date of a new class that has long been searched for: intermediate mass black holes. Due to appear tomorrow in the journal Nature, the discovery has been made by an international team of researchers working with XMM-Newton data, led by Sean Farrell from the Centre d’Etude Spatiale des Rayonnements, now based at the University of Leicester. Stellar-mass black holes (about three to twenty times as massive as the Sun) and supermassive black holes (several million to several thousand million times as massive as the Sun) have long been known to exist. Because of the large gap between these two extremes, scientists have speculated the existence of a third, intermediate class of black holes, with masses between a hundred and several hundred thousand solar masses. Up until now, scientists were unable to confirm that this elusive intermediate class actually existed. Farrell’s team were analysing archived data obtained by XMM-Newton, looking for neutron stars and white dwarves, when they stumbled [...]

XMM-Newton takes astronomers to a black hole’s edge

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Copyright ESA

Using new data from ESA’s XMM-Newton spaceborne observatory, astronomers have probed closer than ever to a supermassive black hole lying deep at the core of a distant active galaxy.

The galaxy – known as 1H0707-495 – was observed during four 48-hr-long orbits of XMM-Newton around Earth, starting in January 2008. The black hole at its centre was thought to be partially obscured from view by intervening clouds of gas and dust, but these current observations have revealed the innermost depths of the galaxy.

“We can now start to map out the region immediately around the black hole,” says Andrew Fabian, at the University of Cambridge, who headed the observations and analysis.

X-rays are produced as matter swirls into a supermassive black hole. The X-rays illuminate and are reflected from the matter before its eventual accretion. Iron atoms in the flow imprint characteristic iron lines on the reflected light. The iron lines are distorted in a number of characteristic ways: they are affected by the speed of the orbiting iron atoms, the energy required for the X-rays to escape the black hole’s gravitational field, and the spin of the black hole. All these features show that the astronomers are [...]

X-ray satellites discover the biggest collisions in the universe

x-ray-satellites-discover-the-biggest-collisions-in-the-universe

Copyright ESA

The orbiting X-ray telescopes XMM-Newton and Chandra have caught a pair of galaxy clusters merging into a giant cluster. The discovery adds to existing evidence that galaxy clusters can collide faster than previously thought.

When individual galaxies collide and spiral into one another, they discard trails of hot gas that stretch across space, providing signposts to the mayhem. Recognising the signs of collisions between whole clusters of galaxies, however, is not as easy.

Undaunted, Renato Dupke and colleagues from the University of Michigan, Ann Arbor, have used ESA’s XMM-Newton and NASA’s Chandra orbiting X-ray observatories, to disentangle the puzzling galaxy cluster, Abell 576.

Previous X-ray observations had hinted that the gas was not moving uniformly across the cluster. Using the superior sensitivity and spectral resolution of XMM-Newton and Chandra’s high spatial resolution, Dupke took readings from two locations in the cluster and saw that there was a distinct difference in the velocity of the gas. One part of the cluster seemed to be moving away from us faster than the other.

The puzzle was that the moving gas itself was cold by astronomical standards. If this gas moved at such high speeds, it should have had a temperature [...]

Mystery spiral arms explained

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Copyright ESA

Using a trio of space observatories, astronomers may have cracked a 45-year old mystery surrounding two ghostly spiral arms in the galaxy M106 (NGC 4258).

The results, obtained by a team from the University of Maryland (USA), took advantage of the unique capabilities of the ESA’s XMM-Newton X-ray observatory, NASA’s Chandra X-ray Observatory, and NASA’s Spitzer Space Telescope.

M106 (also known as NGC 4258) is a spiral galaxy 23.5 million light-years away, in the constellation Canes Venatici. In visible-light images, two prominent arms emanate from the bright nucleus and spiral outward. These arms are dominated by young, bright stars, which light up the gas within the arms.

“But in radio and X-ray images, two additional spiral arms dominate the picture, appearing as ghostly apparitions between the main arms,” says team member Andrew Wilson of the University of Maryland. These so-called “anomalous arms” consist mostly of gas.

“The nature of these anomalous arms is a long-standing puzzle in astronomy,” says Yuxuan Yang, lead author of the team. “They have been a mystery since they were first discovered in the early 1960s.”

By analyzing data from XMM-Newton, Spitzer, and Chandra, the team have confirmed earlier suspicions that the ghostly arms [...]

X-ray evidence supports possible new class of supernova

x-ray-evidence-supports-possible-new-class-of-supernova

Copyright ESA

Evidence for a significant new class of supernova has been found with the European Space Agency’s XMM-Newton and NASA’s Chandra X-ray Observatory. These results strengthen the case for a population of stars that evolve rapidly and are destroyed by thermonuclear explosions. Such ‘prompt’ supernovas could be valuable tools for probing the early history of the cosmos.

A team of astronomers uncovered a puzzling situation when they examined X-ray data from DEM L238 and DEM L249, the remnants of two supernovas in a nearby galaxy. On the one hand, the unusually high concentration of iron atoms implied that the remnants are the products of thermonuclear explosions of white dwarf stars, a well-known type of supernova known as ‘Type Ia’. On the other hand, the hot gas in the remnants was much denser and brighter in X-rays than typical Type Ia remnants.

A white dwarf, the dense final stage in the evolution of a sun-like star, is a very stable object and will not explode on its own. However, if a white dwarf has a close companion star it can grow beyond a critical mass by pulling gas off the companion and explode.

Computer simulations of Type Ia supernova remnants [...]

ESA’s XMM-Newton gains deep insights into the distant Universe

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Copyright ESA

Using XMM-Newton, astronomers have obtained the world’s deepest ‘wide screen’ X-ray image of the cosmos to date. Their observations show newly discovered clusters of galaxies and provide insights into the structure of the distant Universe…

Unlike grains of sand on a beach, matter is not uniformly spread throughout the Universe. Instead, it is concentrated into galaxies like our own which themselves congregate into clusters. These clusters are ‘strung’ throughout the Universe in a web-like structure. Astronomers have studied this large-scale structure of the nearby Universe but have lacked the instruments to extend the search to the large volumes of the distant Universe.

Thanks to its unrivalled sensitivity, in less than three hours, ESA’s X-ray observatory XMM-Newton can see back about 7000 million years to a cosmological era when the Universe was about half its present size, and clusters of galaxies more tightly packed. Marguerite Pierre, CEA Saclay, France, with a European and Chilean team, used this ability to search for remote clusters of galaxies and map out their distribution.

The work heralds a new era of studying the distant Universe. The optical identification of clusters shows only the galaxies themselves. However, X-rays show the gas in between [...]

Is the Universe older than expected?

is-the-universe-older-than-expected

Copyright ESA

An analysis of 13.5 thousand million-year-old X-rays, captured by ESA’s XMM-Newton satellite, has shown that either the Universe may be older than astronomers had thought or that mysterious, undiscovered ‘iron factories’ litter the early Universe.

ESA’s Norbert Schartel and colleagues from the Max-Planck-Institut für extraterrestrische Physik,Germany, found more iron than anyone thought possible in the extremely distant celestial object, APM 8279+5255. The object is a quasar, that is, a young galaxy containing an incredibly bright central region, caused by gas falling into a giant black hole.

APM 8279+5255 is 13.5 thousand million light years away. Scientists know this because they have estimated a property of its light known as the red shift, which is caused by the expansion of the Universe stretching the wavelengths of light emitted by the celestial object. XMM-Newton’s data showed that iron was three times more abundant in the quasar than in our Solar System.

Since iron is released by exploding stars, according to precise physical phenomena, and scientists think it builds up across the Universe gradually with time. The Solar System formed just 5 thousand million years ago, so it should contain more iron than the quasar, which formed over 13.5 thousand million [...]