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Photo: A newfound population of heavily absorbed active galaxies (orange curve) is thought to make
the greatest contribution to the cosmic X-ray background (light blue). Both have similar spectral
shapes and peak at similar energies. Adding in the known contributions from less-absorbed active
galaxies (yellow and purple) appears to fully account for the background.
Credit: NASA/Goddard Space Flight Center |
Swift Survey Finds 'Missing' Active GalaxiesResearchers from the MPE and the Kavli Institute for Particle Astrophysics and Cosmology at SLAC have confirmed that a high number of X-ray sources, thought to be massive black holes, are deeply hidden in our local universe. Obscured by dust and gas, the objects are difficult to spot from Earth.The new analysis led by Davide Burlon, a Ph.D. student at MPE, will significantly impact the study of the universal X-ray background. Using data from the Swift-BAT telescope, the researchers examined a key source of the cosmic X-ray background: galaxies with massive black holes at their centers. Gas and dust spiral around the black hole, radiating high levels of X-ray light. These bright X-ray centers are known as active galactic nuclei, or AGNs. Only a small portion of very high-energy X-rays from extremely absorbed AGN reach Earth, so these objects would not be immediately visible in the telescope data from Swift. Burlon and collegues studied a sample of X-ray sources in the local universe (an area out to about 326 million light years from Earth) in an effort to identify previously unseen extremely absorbed AGNs. They combined archival data with three years of data from Swift-BAT. Together they confirmed experimentally that between 20 and 30 percent of all AGN in the local universe are extremely absorbed. These results line up with theories on this subject. People have tried to look for these objects for a very long time - now the team has found more than anyone has found in the past. [ ![]() ![]() ![]() |
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Photo: The "La Calabria nel Mondo" award is given to Sandra Savaglio by Antonio Catricalà, the President
of the independent organisation AGCM, on October 12, 2010.
Copyright: Andrea Cenni |
"Calabria in the World " awarded to MPE scientist Sandra SavaglioThis October,![]() Every year, C3 International honours distinguished persons from Calabria, successful in their work in the fields of science, culture, sports, and journalism, who have been ambassadors of Calabria and its values around the world. Among past honourees are Renato Dulbecco, Nobel Prize laureate for Medicine in 1975, Leon Panetta, Director of the Central Intelligence Agency, Santo Versace from the fashion house Versace, and José Serra, a presidential candidate of the Brazilian elections in 2002. Apart from Savaglio, 14 other people received the award this year. Among the guests were Jo Champa, former model for Gianni Versace and actress (her latest movie was "Somewhere" which won the Golden Lion at the Venice Film Festival), and the Minister of Cultural Heritage Sandro Bondi. Designed by the well-known artist Gerardo Sacco, this year's award represents a scene from one of the oldest surviving illuminated manuscripts of the Gospels. Written in the 6th century, the "Codex purpureus Rossanensis" is now located at the Cathedral of Rossano in Calabria. |
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Dust in the surrounding of a GRB will dim and redden the light before it reaches the observer.
Credit: MPE / J. Greiner |
Illuminating dark bursts with GRONDGamma-ray bursts are among the most energetic events in the Universe, but some appear curiously faint in visible light. An international team of astronomers led by the Max Planck Institute for Extraterrestrial Physics have now conducted the biggest study to date of these so-called dark gamma-ray bursts, using the GROND instrument on the 2.2-metre MPG/ESO telescope at La Silla in Chile. The scientists conclude that these gigantic explosions do not require exotic explanations; their faintness is now fully explained by a combination of causes, the most important of which is the presence of dust between the Earth and the explosion.[ ![]() |
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The evolution of the abundance of 26Al in a stellar group.
Picture: R. Voss. |
INTEGRAL helps unravel the tumultuous recent history of the solar neighbourhoodAnalysing new observations in gamma rays with ESA's INTEGRAL observatory, astronomers from the Max Planck Institute for Extraterrestrial Physics and other institutions found evidence that only a few million years ago massive stars enriched our cosmic neighbourhood with heavy elements. The scientists exploited the radioactive decay of an isotope of aluminium, produced in the late stages of a massive star's lifetime, to estimate the age of stars in the nearby Scorpius-Centaurus association, the closest group of young and massive stars to the Sun.[ ![]() |
![]() A giant gamma-ray structure was discovered by processing Fermi all-sky data at energies
from 1 to 10 billion electron volts.
Picture: NASA/DOE/Fermi LAT/D. Finkbeiner et al.. |
Fermi telescope finds giant gamma-ray bubbles in the Milky WayA team of scientists has found a previously unseen structure in the Milky Way by processing publicly available data from Fermi's Large Area Telescope (LAT). The LAT is the most sensitive and highest-resolution gamma-ray detector ever launched and the MPE is involved in scientific analysis of the LAT data. The newly detected feature spans 50,000 light-years and may be the remnant of an eruption from a supersized black hole at the centre of our galaxy. A paper about the findings has been accepted for publication in the Astrophysical Journal.[ ![]() |
![]() Yasuo Tanaka
Image: MPE (D. Grupe)
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Tanaka honoured as "Person of Cultural Merit"A very high japanese accolade this year goes to Dr. Yasuo Tanaka, scientific member at the Max Planck Institute for Extraterrestrial Physics, together with 16 other people chosen for this prestigious award. The high-energy astrophysicist is not only a distinguished member of the global scientific community; he also actively promotes the academic exchange between Japan and foreign countries. [ ![]() |
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Cluster Promotion prize for MPE student Thomas KrühlerDuring the "Universe Cluster Science Week", 11.-14. October, Dr. Thomas Krühler from the Max Planck Institute for Extraterrestrial Physics presented his award winning thesis on "Advanced Photometric Studies of Gamma-Ray Burst Afterglows". For the third time, the Excellence Cluster Universe awarded two outstanding dissertations in the fields of astro-, nuclear and particle physics in the categories "experiment" and "theory".[ ![]() |
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Nova Cygni (V407 Cyg) is at the center of the image.
Credit: NASA/DOE/Fermi LAT Collaboration |
News from a nova: gamma raysFor the first time, astronomers have detected gamma-rays from a nova, a finding that surprised both observers and theorists. The discovery using NASA's Fermi Gamma-ray Space Telescope overturns the notion that novae explosions lack the power to emit such high-energy radiation.Gamma rays are the most energetic form of light, and Fermi's Large Area Telescope (LAT) detected the nova for 15 days. Scientists believe the emission arose as a high velocity shock wave raced from the site of the explosion. A paper detailing the discovery appeared in the journal Science on 13. August 2010. [ ![]() |
![]() NGC 2207
Image: ESO
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Massive Black holes "switch on" due to galaxy collisionThe centre of most galaxies harbours a massive Black Hole. So does our Milky Way - the exotic object there however is pretty calm, unlike some supermassive gravity monsters in other galaxies. Scientists at the Max Planck Institute for Extraterrestrial Physics and other institutions around the world have now analysed 199 of these galaxies and discovered what makes the black holes at the galaxy centre become active: The black holes switched on some 700 million years ago after major galaxy merger events. (The Astrophysical Journal, in press) For more information see the ![]() |
![]() Kirpal Nandra
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Kirpal Nandra appointed as new Director at the Max Planck Institute for Extraterrestrial PhysicsThe open position on the Board of Directors at the Max Planck Institute for Extraterrestrial Physics is now filled: Kirpal Nandra joins the institute as new director and head of the high-energy research group. His long experience in X-ray astronomy actively complements the two other astrophysical groups at the institute that study objects such as stars, galaxies and the large scale structure in the universe with optical, infrared and sub-millimetre astronomy.For more information see the ![]() Image: MPE
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![]() Image: ESA/XMM-Newton
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Novel observing mode on XMM-Newton opens new perspectives on galaxy clustersSurveying the sky with XMM-Newton, scientists at the Max-Planck-Institute for Extraterrestrial Physics and other institutes have discovered two massive galaxy clusters, confirming a previous detection obtained through observations of the Sunyaev-Zel'dovich effect, the 'shadow' they cast on the Cosmic Microwave Background. The discovery, made possible thanks to a novel mosaic observing mode recently introduced on ESA's X-ray observatory, opens a new window to study the Universe's largest bound structures in a multi-wavelength approach.For more information see the ![]() |
![]() In this false colour image arrows indicate galaxies that are likely located at the same distance. The combination of the X-ray detection and the collection of massive galaxies unequivocally proves a real, gravitationally bound cluster. |
Most distant galaxy cluster revealed by invisible lightAn international team of astronomers from Germany and Japan has discovered the most distant cluster of galaxies known so far - 9.6 billion light years away. The X-ray and infrared observations showed that the cluster hosts predominantly old, massive galaxies, demonstrating that the galaxies formed when the universe was still very young. These and similar observations therefore provide new information not only about early galaxy evolution but also about history of the universe as a whole.For more information see ![]()
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![]() Image: S. Giodini, A. Finoguenov/MPE |
Black Holes - "Gas Blowers" of the UniverseSupermassive black holes with the mass of many millions of stars have been detected at the centre of many large galaxies. A super-massive black hole acts like a lurking "monster" at the centre of the galaxy which swallows the surrounding material through the intensity of its gravitational pull. X-ray observations indicate that a large amount of energy is produced by the in-fall of matter into a black hole, and ejected in powerful jets. Astronomers from the Max Planck Institute for Extraterrestrial Physics have now shown that these jets eject matter not only from their host galaxies but even the gas between the galaxy group members.(Astrophysical Journal, 1 May 2010) For further information see the ![]()
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![]() HM Cancri Artwork: Rob Haynes, Louisiana State University |
Most extreme binary shows orbital period of a mere 5 minutesThat is real fast: Two suns orbit each other in a mere 5.4 minutes. This makes HM Cancri the binary star system with by far the shortest known orbital period - and at the same time the smallest binary known. Its size is equivalent to no more than a quarter of the distance from the Earth to the Moon, about 100,000 kilometres. This has been shown by an international team of astronomers from the Max Planck Institute for Extraterrestrial Physics and other institutions.![]() ApJ 711, L138-L142 (2010); ![]() ![]() ![]()
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![]() XMM-Newton satellite ![]() MPE scientists discussing XMM data |
10th Anniversary of XMM-NewtonThe MPE was highly involved in this mission during the telescope development and test, it provides the EPIC-pn camera, and runs the survey science center.The primary scientific objective of XMM-Newton is to perform high throughput spectroscopy of cosmic X-ray sources over a broad band of energies ranging from 0.1 keV to 10 keV. The XMM-Newton spacecraft payload includes three highly-nested grazing-incidence mirror modules of type Wolter I coupled to reflection grating spectrometers and X-ray charge-coupled device (CCD) cameras with resolving powers ranging from 10 up to 1000 as well as one small optical/UV telescope. For XMM-Newtons 10-year anniversary, the TV station EuroNews concentrated on the X-ray satellite in its broadcast "space", which was produced in collaboration with the European Space Agency ESA and the MPE. Links:
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![]() The Quasar J004457+4123 (encircled object on the left upper panel) looks like a weak point of light, hardly to be distinguished from the huge number of stars in the Andromeda galaxy (right). Copyright: TLS Tautenburg |
Spectacular flare of a distant QuasarUsing data from several telescopes, an international team of scientists from the MPE, the Tautenburg observatory and others have now confirmed that an object observed in 1992 as a so-called "nova" in our neighbouring Andromeda galaxy is actually a much more distant quasar with a uniquely intense light burst. The most likely explanation for the magnitude and shape of the light curve is that a massive star came too close to the gigantic Black Hole at the centre of this distant galaxy, where it was ripped apart and swallowed by the gravitational pull of the black hole.
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![]() X-ray emission in the COSMOS field. Credit: ESA |
XMM-Newton traces dark matter in faint, distant galaxy groups
Observations of faint and distant galaxy groups made with the European Space Agency's XMM-Newton observatory have been used to probe the evolution of dark matter. The results of the study by researchers including scientists from the Max-Planck-Institute for extraterrestrial Physics, Germany, are reported in the 20 January issue of The Astrophysical Journal. ![]() ![]() Contact: ![]() ![]() |
![]() Photon arrival times (for details see Nature paper) Image: Nature |
Testing Einstein's Special Relativity with
Gamma-Ray Burst Photons Einstein’s special relativity postulates that observers see the same speed of light in vacuum, independent of photon-energy. At a fundamental scale (the Planck scale), quantum effects are expected to affect the nature of space–time, and Lorentz invariance might become violated. MPE scientists have been involved in a key test of such violation, namely the possible variation of photon speed with energy over cosmological light-travel times. This became possible by the detection of emission from keV up to 31 GeV energies with the Fermi satellite's instruments (GBM, LAT) from the distant and short gamma-ray burst GRB090510. No violation of Lorentz invariance was found to 1 part in 1017, placing the tightest limits so far and eliminating some quantum-gravity theories. (Abdo et al., Nature 462, Oct 2009) Links: Contact:
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![]() Signing of contract from left: Reichle, Wörner, Perminov ![]() eROSITA Images: MPE |
DLR and Roscosmos sign technical agreement for X-ray telescope eROSITA
With seven X-ray eyes the eROSITA telescope will scan the Universe
for black holes and dark matter. Today board members of the German
Aerospace Center (DLR) and the Russian Federal Space agency Roscosmos
signed an agreement which defines all organisational and technical
conditions.
Contact:
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![]() Image Credit: Rochester Institute of Technology |
Living Fossils Hold Record of "Supermassive" Kick -
When two galaxies and the supermassive black holes in their centres merge,
the resulting recoil can catapult the black hole from the galaxy. Scientists
of the Rochester Institute of Technology (RIT), MPE and Johns Hopkins University
have now found that the stellar clusters around these black holes show very unusual
properties and so open up a new possibility to study the event in detail. The
stars around evicted black holes orbit at a very high velocity, because only
stars orbiting faster than the kick velocity remain attached to the black hole
after the kick. As a kind of living fossils of a distant epoch they can shed
light on the turbulent past of merging galaxies in nearby clusters.
Contact:
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In this picture the afterglow of GRB090423 is the red object shining only
in some of the used color channels. Image: GROND/MPE |
Gamma-Ray Burst 090423 detected at a record distance
Following a Gamma-Ray burst alarm of the NASA Swift Satellite on April
23, several groups world-wide started searching for the afterglow emission.
The MPE built
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