Betelgeuse in Orion has been fascinating astronomers in the recent months because of its unusually strong decline in brightness. It has even been suggested that this supergiant star was preparing for a supernova explosion. A team led by Thavisha Dharmawardena (MPIA Heidelberg) shows that most likely unusually large star spots on the surface of Betelgeuse have caused the dimming. Their results rule out the previous conjecture that dust, recently ejected by Betelgeuse, obscured the star. Karl Menten and Axel Weiß (both MPIfR Bonn) are co-authors of the study, based on submillimeter observations made with with the James-Clerk-Maxwell-Telescope on Mauna Kea, Hawaii and the Atacama Pathfinder Experiment in the Atacama desert in Chile. (MPIA press release, 29 June 2020). [more]
An observation campaign led by ESA’s XMM-Newton reveals Swift J1818.0−1607 as the youngest pulsar ever seen – the remnant of a once-massive star that is also a ‘magnetar’, sporting a magnetic field some 70 quadrillion times stronger than that of the Earth. Alessandro Ridolfi (INAF & MPIfR) is one of the authors of the original paper in ApJ Letters (ESA Press Release, 17 June 2020). [more]
Jae-Young Kim, Max Planck Institute for Radio Astronomy, was recently awarded with the Otto Hahn Medal of the Max Planck Society for the high-resolution studies of the innermost structure and the jet formation in the environment of supermassive black holes. The Otto Hahn Medal is awarded in recognition of outstanding achievements from the initial creative period of young scientists (MPG Release, 17 June 2020). [more]
Celebrating the 10th anniversary of the European Low-frequency Radio telescope LOFAR, the ASTRON institute in the Netherlands presents a series of highlight articles on science and technology results with LOFAR. One of the German LOFAR stations is operated at the Effelsberg Radio Observatory (ASTRON News, June 2020). [more]
For the 10th anniversary of SOFIA’s first light flight the German SOFIA institute (DSI) presents some of the highlights SOFIA achieved in its mission so far. It also includes a number of discoveries with the German GREAT/upGREAT receiver (DSI News Release, 27 May 2020, in German language). [more]
Ten years ago, the Stratospheric Observatory for Infrared Astronomy (SOFIA), jointly operated by NASA and DLR, first peered into the cosmos. Since the night of May 26, 2010, SOFIA’s observations of infrared light, invisible to the human eye, have made many scientific discoveries about the hidden universe. Ten important discoveries with SOFIA are featured here, including the first detection of the HeH+ molecule and the investigation of a stellar wind from a new-born star in the Orion nebula, both with the German GREAT/upGREAT receiver onboard SOFIA (NASA News Feature, 18 May 2020). [more]
Comparing data of the IceCube neutrino observatory and a VLBI-sample of Active Galactic Nuclei (AGN), a team of Russian astrophysicists including Yuri Kovalev (Lebedev Institute, MIPT & MPIfR) connects ultra-energetic neutrinos to radio flares at the centers of distant active galaxies caused by the infall of matter towards their central supermassive black holes (MIPT Press Release 13 May 2020, based on A. Plavin et al. 2020, ApJ Vol. 894, no. 2). [more]
John (Jiannis) Seiradakis, Professor emeritus for Astrophysics at Aristotle University Thessaloniki, died in the night from May 02 to 03, 2020. At MPIfR, a lot of people will remember him as a former employee, a frequent guest and certainly as friend of the institute and many of its students, postdocs and staff (Obituary of the Alumni of Aristotle University, in Greek language). [more]
The first detection of strong radio pulses of the magnetar candidate Swift J1818.0-1607 was done with the Effelsberg radio telescope (ATel #13553 from March 14, 2020). Subsequent timing of the source with both, Effelsberg and Jodrell Bank radio telescopes determined the spin-evolution of the source, its age and its magnetic field, confirming the nature of the source as a very young magnetar (ATel #13559 from March 17, 2020). [more]
The next observation campaign of the Event Horizon Telescope (EHT) was due to start at the end of March 2020. Regrettably, several participating observatories have shut down in response to the growing coronavirus (COVID-19) crisis and it was necessary to cancel the observations for 2020 (EHT News Release, 17 March 2020). [more]
Radio observations using 21 telescopes of the European VLBI Network (EVN) including the Effelsberg 100-m- telescope have revealed that a cosmic explosion, called AT2018cow most likely formed a neutron star with an extremely powerful magnetic field - known as a magnetar (JIVE Press Release, 28 January 2020). [more]
The Albert Einstein Society Berne awards its 2020 Einstein Medal to the international collaboration of the Event Horizon Telescope (EHT) in recognition of the groundbreaking imaging of the shadow of the supermassive black hole in the center of the distant galaxy Messier M87. The public ceremony will take place on 27 May 2020 (Albert Einstein Society, 29 January 2020). [more]
The top prize of the High Energy Astrophysics Division (HEAD) of the American Astronomical Society (AAS) has been awarded to Dr. Sheperd Doeleman (Harvard CfA) and the Event Horizon Telescope team for the landmark image and analysis of the first shadow of a black hole. (AAS Press Release, 28 January 2020). [more]
An international team led by researchers at the University of California and at the Max Planck Institute for Radio Astronomy (Bonn, Germany) set a new record with observations at the W. M. Keck Observatory on Hawaii: the brightest radiation outburst so far of the supermassive black hole at the center of the Milky Way (Sgr A*). This discovery was made possible by the high sensitivity and high resolution near-infrared camera NIRC2 at one of the two 10-m telescopes on Mauna Kea. Gunther Witzel, researcher at the MPIfR and contributing author of the study, has analyzed the variable brightness of Sgr A* since 2008:”In 24 years of observations we’ve never seen Sgr A* that bright. This is a very extraordinary observation.” Sgr A* is known as a highly variable source at the center of our Galaxy. However, the nature and origin of the variable emission is not fully understood. It is commonly explained to be created by the heated matter in the direct vicinity of the supermassive black hole shortly before it is accreted. The recently observed outburst is twice the brightness of the previous record. In the course of 90 minutes it then decreased by a factor of 75, the most dramatic evolution observed so far. It remains unclear if and in what way this observation is related to objects like the star S0-2 or the gas cloud G2 which very recently (in 2018 and 2014, respectively) went through closest approach and might have contributed large amounts of gas to the accretion stream. Anton Zensus, director at the Max Planck Institute and director of the board of the Event Horizon Telescope (EHT), pointed out the importance of this observation: “Extreme states of Sgr A* shed light on the physical processes at work. These observations provide complementary information for our ongoing effort to image the black hole at heart of our Milky Way with the EHT.“ The publication will be published in the Astrophysical Journal (Press Release UCLA, 11. September 2019).
In a detailed study of a star orbiting the supermassive black hole at the center of our Galaxy, researchers report that Einstein’s theory of general relativity (GR) accurately describes motion around this massive structure. Tuan Do, Andrea Ghez and their colleagues including Gunther Witzel from the Max Planck Institute for Radio Astronomy in Bonn, Germany, report novel spectral data and expanded analyses. The findings are presented in this week’s issue of the magazine „Science“ (UCLA Press Release, 25 July 2019).