Highlights

A wobbling magnetised star challenges the origin of repeating fast radio bursts

April 08, 2024

The rapid decay of a magnetar’s precession after an X-ray outburst likely rules out free precession as their origin

An international research team led by Gregory Desvignes from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has used the Effelsberg and Jodrell Bank radio telescopes to observe the precessing magnetar XTE J1810-197 — a highly magnetised and ultra-dense neutron star — shortly after its X-ray enhanced activity and radio reactivation. This precession damped on a timescale of a few months challenging some models used to explain the origin of the mysterious repeating fast radio bursts. more

Lightest black hole or heaviest neutron star?

January 18, 2024

MeerKAT uncovers a mysterious object at the boundary between black holes and neutron stars

An international team of astronomers, led by researchers from the Max Planck Institute for Radio Astronomy, have used the MeerKAT radio telescope to discover an intriguing object of an unknown nature in the globular cluster NGC 1851. The massive object is heavier than the heaviest neutron stars known and yet simultaneously lighter than the lightest black holes known and is in orbit around a rapidly spinning millisecond pulsar. This could be the first discovery of the much-coveted radio pulsar - black hole binary; a stellar pairing that would allow new tests of Einstein’s general relativity. more

Extreme stars share unique properties that may provide a link to mysterious sources

November 23, 2023

A universal relation for pulsars, magnetars and potentially fast radio bursts

An international research team led by Michael Kramer and Kuo Liu from the Max Planck Institute for Radio Astronomy in Bonn, Germany, have studied a rare species of ultra-dense stars, so called magnetars, to uncover an underlying law that appears to apply universally to a range of objects known as neutron stars. This law gives insight into how these sources produce radio emission and it may provide a link to the mysterious flashes of radio light, Fast Radio Bursts, that originate from the distant cosmos. more

New radio astronomical observations confirm unintended electromagnetic radiation emanating from large satellite constellations

July 05, 2023

Scientists use the LOFAR telescope to observe low-frequency radio waves from satellites in large constellations for the first time

Scientists from a number of leading research institutions including the Max Planck Institute for Radio Astronomy in Bonn, Germany, used the Low Frequency Array (LOFAR) telescope to observe 68 of SpaceX’s satellites. The authors conclude that they detected "unintended electromagnetic radiation" emanating from onboard electronics. This is different from communications transmissions, which had been the primary focus for radio astronomers so far. The unintended radiation could impact astronomical research. They encourage satellite operators and regulators to consider this impact on radio astronomy in spacecraft development and regulatory processes alike. more

A new view of the Universe

June 29, 2023

Clock-like precision of pulsars opens a new window in the gravitational wave spectrum

An international collaboration of European astronomers including scientists from the Max Planck Institutes for Radio Astronomy and Gravitational Physics, together with Indian and Japanese colleagues, have published the results of more than 25 years of observations from six of the World's most sensitive radio telescopes. Along with other international collaborations, the European and Indian Pulsar Timing Arrays have independently found evidence for ultra-low-frequency gravitational waves, expected to come from pairs of supermassive black holes found in the centres of merging galaxies. These results are a crucial milestone in opening a new, astrophysically rich window in the gravitational wave spectrum. more

Gamma-ray eclipses shed new light on spider pulsars

January 26, 2023
Seven rare eclipsing binaries identified and five neutron stars weighed

Mankind has watched the cosmic ballet of eclipses for millennia. Solar and lunar eclipses, those of Jupiter’s moons, and stellar occultations by planets and asteroids have also provided new physical measurements and insights about our Universe. Using NASA’s Fermi Gamma-ray Space Telescope, astronomers have now identified seven rare stellar binary systems in which a neutron star is eclipsed by its stellar companion. This allowed the international research team led by scientists from the Max Planck Institute for Gravitational Physics (Albert Einstein Institute) in Hannover and including researchers from MPIfR Bonn to weigh those neutron stars. Precisely measuring neutron star masses improves our understanding of matter in extreme conditions and has implications for fundamental physics. In the future, these seven binary systems could also provide new opportunities to observe Einstein’s theory of general relativity in action. more

Nine new and exotic creatures for the pulsar zoo

January 25, 2023

New discoveries from the Transients and Pulsars with MeerKAT Project

Nine millisecond pulsars, most of them in rare and sometimes unusual binary systems: that is the first result of a targeted survey with the South African MeerKAT telescope array. An international team of astronomers with significant contributions from researchers at the Max Planck Institute for Gravitational Physics (Albert Einstein Institute, AEI) and the Max Planck Institute for Radio Astronomy (MPIfR) selected 79 unidentified pulsar-like sources from observations of NASA’s Fermi Gamma-ray Space Telescope and observed them at radio frequencies with MeerKAT. Using this tried-and-tested method with a next-generation telescope array has significant advantages over previous surveys. The team discovered nine rapidly rotating neutron stars, most of them with unusual properties.

They performed multi-wavelength follow-ups, finding gamma-ray pulsations from two of these objects, optical counterparts, as well as X-rays from another one of the systems. AEI scientists also searched for continuous gravitational waves from one of the neutron stars. These results emphasize the value of targeted searches for radio pulsars in unidentified gamma-ray sources and hold promise for the future: the researchers are certain that several more millisecond pulsars can be discovered by future observations. more

RAS Group Award 2023 goes to MeerKAT

January 13, 2023

The MeerKAT radio telescope in South Africa receives prestigious award of the Royal Astronomical Society

The MeerKAT team is awarded the Group Award of the Royal Astronomical Society for a series of spectacular observations in radio astronomy, the highlight being the images of the Galactic Centre region and the spectacular radio bubbles. In addition, the MeerKAT team have supported the development of science and technology in Africa and stress-tested technology for the Square Kilometre Array.

The Max Planck Institute for Radio Astronomy (MPIfR) and the Max-Planck-Gesellschaft in Germany, are involved in the MeerKAT project by providing a set of receivers in the S-Band frequency range for each of the dishes and also by an extension project increasing the total number of MeerKAT dishes from 64 to 84, thus increasing sensitivity, spatial resolution and image quality of the telescope.

Coincidentally, a new science result based on MeerKAT observations led by MPIfR scientists is published on the same day which has solved a 20-year old mystery: pulsar observations of the globular cluster M30 led to the re-detection of a long-time missing millisecond pulsar in a highly eccentric binary orbit. The findings are published today in The Astrophysical Journal Letters (ApJL). more

Energetic Winds blow from the Triangulum Galaxy

October 25, 2022

Radio observations reveal a complex scenario for the interplay between star formation and the interstellar medium in the galaxy M33

Studying the interplay between massive star formation and the interstellar medium is important to understand the evolution of galaxies. An international research team led by Fatemeh Tabatabaei including several scientists from the Max Planck Institute for Radio Astronomy in Bonn, Germany, performed high-resolution radio observations of the local group galaxy Messier 33 with the Karl G. Jansky Very Large Array (VLA). Their results show a direct connection between molecular gas and star formation exists in M33. Massive star formation amplifies the magnetic field and increases the number of high-energy cosmic ray electrons, which can help the onset of winds and outflows. more

"Sleeping" black hole discovered outside our galaxy

July 20, 2022

An international research team including Norbert Langer (AIfA & MPIfR Bonn) has detected a stellar-mass black hole outside the Milky Way, in the Large Magellanic Cloud, a companion of the Milky Way. The discovery was made during a six-year observing campaign with the Very Large Telescope (VLT) at the European Southern Observatory (ESO). The results have been published in the journal Nature Astronomy (University of Bonn press release, July 18, 2022, in German language). more

A Slowly Rotating Neutron Star

May 30, 2022

Unusual neutron star spinning every 76 seconds is discovered in stellar graveyard

An international team of scientists including astronomers from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has discovered an unusual radio emitting neutron star, which rotates extremely slowly, completing one rotation every 76 seconds. The team, led by members of the MeerTRAP (More Transients and Pulsars) group at The University of Manchester say it is a unique discovery as it resides in the neutron star graveyard where they do not expect any pulsations at all. The discovery was made using the MeerKAT radio telescope in South Africa. more

Astronomers reveal first image of the black hole at the heart of the Milky Way

May 12, 2022

Breakthrough discovery: EHT´s unprecedented observations improve our understanding of what happens at the very centre of our galaxy

Astronomers have unveiled the first image of the supermassive black hole at the centre of our own Milky Way galaxy. This result provides overwhelming evidence that the object is indeed a black hole and yields valuable clues about the nature of such giants, which are thought to reside at the centers of most galaxies. The image was produced by a global research team called the Event Horizon Telescope (EHT) Collaboration, using observations from a worldwide network of radio telescopes. The Max Planck Institute for Radio Astronomy (MPIfR) in Bonn plays a major role in all the aspects of this discovery, from founding and establishing the EHT collaboration to the final production and interpretation of the data. more

The Hunt for the Gravitational Wave Background

April 07, 2022

NASA’s FERMI Satellite Hunts for Extremely Long-wavelength Gravitational Wave Signals

Coalescing supermassive black holes in the centers of merging galaxies fill the universe with low-frequency gravitational waves. Astronomers have been searching for these waves by using large radio telescopes to look for the subtle effect these spacetime ripples have on radio waves emitted by pulsars within our Galaxy. Now, an international team of scientists has shown that the high-energy light collected by NASA’s Fermi Gamma-ray Space Telescope can also be used in the search. Using gamma rays instead of radio waves yields a clearer view to the pulsars and provides an independent and complementary way to detect gravitational waves. more

Cosmic flashes pinpointed to a surprising location in space

February 23, 2022

Localisation of a recurring source of radio flashes in the nearby galaxy M81

Astronomers have been surprised by the closest source of mysterious flashes in the sky called fast radio bursts. Precision measurements with radio telescopes reveal that the bursts are made among old stars, and in a way that no one was expecting. The source of the flashes, in nearby spiral galaxy M 81, is the closest of its kind to Earth. more

The Search for an Isotropic Gravitational Wave Background

January 12, 2022

World-wide radio telescope network enhances signal that may hint at ultra-low frequency gravitational waves

An international team of astronomers including a number of scientists from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has announced the results of a comprehensive search for a background of ultra-low frequency gravitational waves. These light-year-scale ripples, a consequence of general relativity, permeate all of spacetime and could originate from mergers of the most massive black holes in the Universe or from events occurring soon after the formation of the Universe in the Big Bang. more

Einstein wins again

December 13, 2021

The theory of general relativity passes a range of precise tests set by pair of extreme stars

An international team of researchers from ten countries led by Michael Kramer from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has conducted a 16-year long experiment to challenge Einstein’s theory of general relativity with some of the most rigorous tests yet. Their study of a unique pair of extreme stars, so called pulsars, involved seven radio telescopes across the globe and revealed new relativistic effects that were expected and have now been observed for the first time. Einstein’s theory, which was conceived when neither these types of extreme stars nor the techniques used to study them could be imagined, agrees with the observation at a level of at least 99.99%. more

Jet from giant galaxy M87: Computer modelling explains black hole observations

November 22, 2021
An enormous jet of particles emitted by the giant galaxy M87 can be observed astronomically in various wavelengths. Dr. Alejandro Cruz Osorio and Professor Luciano Rezzolla from Goethe University Frankfurt together with an international team of scientists including Professor Michael Kramer (MPIfR bonn) within the framework of the BlackHoleCam research project has succeeded in developing a theoretical model of the morphology of this jet using complex supercomputer calculations. The images from these calculations provide an unprecedented match with astronomical observations and confirm Einstein’s theory of general relativity (Press Release, Frankfurt University, November 04, 2021). more

Towards the Detection of the Nanohertz Gravitational-wave background

October 27, 2021

The European Pulsar Timing Array provides a significant step forward

The European Pulsar Timing Array collaboration reports on the outcome of a 24 year observing campaign with five large-aperture radio telescopes in Europe, resulting in a candidate signal for the since-long sought gravitational wave background due to in-spiraling supermassive black-hole binaries. The collaboration brings together teams of astronomers around the largest European radio telescopes including the 100-m Effelsberg radio telescope of the Max Planck Institute for Radio Astronomy in Bonn, Germany, as well as groups specialized in data analysis and modelling of gravitational wave signals. Although a detection cannot be claimed yet, this represents a significant step in the effort to finally unveil gravitational waves at very low frequencies in the Nanohertz regime. The candidate signal has emerged from an unprecedented detailed analysis using two independent methodologies and shares strong similarities with results found from the analyses of other teams. more

Over A Thousand Cosmic Explosions in FRB 121102 Detected by FAST

October 13, 2021
An international research team led by Di Li and Pei Wang (National Astronomical Observatories of the Chinese Academy of Sciences) including Marylin Cruces, Michael Kramer and Laura Spitler from the MPIfR in Bonn caught an extreme episode of cosmic explosions from the Fast Radio Burst FRB 121102, using the Five-hundred-meter Aperture Spherical radio Telescope (FAST). A total of 1,652 independent bursts were detected within 47 days (Nature Paper & NAOC Press release, October 13, 2021). more

GLOSTAR - tracing atomic and molecular gas in the Milky Way

July 22, 2021

Two powerful telescopes provide the most detailed radio maps of the Northern Galactic Plane

By combining two of the most powerful radio telescopes on Earth, an international team of researchers led by the Max Planck Institute for Radio Astronomy (MPIfR) in Bonn, created the most sensitive maps of the radio emission of large parts of the Northern Galactic plane so far. The data were taken with the Karl G. Jansky Very Large Array (VLA) in New Mexico in two different configurations and the 100-m Effelsberg telescope near Bonn. This provides for the first time a radio survey covering all angular scales down to 1.5 arc-seconds, the apparent size of a tennis ball lying on the ground and seen from a flying plane. Contrary to previous surveys, GLOSTAR observed not only the radio continuum in the frequency range from 4-8 GHz in full polarization, but simultaneously also spectral lines that trace the molecular gas (from methanol and formaldehyde) and atomic gas via radio recombination lines. more

FAST Radio Telescope Detects 3D Spin-velocity Alignment in a Pulsar

May 07, 2021

Based on observations from the Five-hundred-meter Aperture Spherical radio Telescope (FAST) in China, an international research team led by Jumei Yao, including Michael Kramer from the MPIfR, found the first evidence for three-dimensional (3D) spin-velocity alignment in pulsars.The study was published in Nature Astronomy on May 6 (CAS-Press Release, May 07, 2021).

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A new telescope to study Einstein’s theory and Nature’s most compact objects

May 06, 2021

Using the South African MeerKAT telescope, astronomers started to systematically explore binary pulsars for tests of gravity

An international group of astronomers, led by the Max Planck Institute for Radio Astronomy (MPIfR) in Bonn, Germany and the University of British Columbia (UBC) in Vancouver presents the first results of a large program to use South Africa’s MeerKAT radio telescope to test the theories of Einstein with unprecedented precision.

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The Discovery of 8 New Millisecond Pulsars

April 28, 2021

South Africa’s MeerKAT Radio Telescope explored the central regions of globular clusters in search of very weak pulsars

A group of astronomers, led by the Italian National Institute of Astrophysics (INAF) and the Max Planck Institute for Radio Astronomy (MPIfR) in Bonn, Germany, has discovered 8 millisecond pulsars located within dense clusters of stars, known as “globular clusters”, using South Africa’s MeerKAT radio telescope. Millisecond pulsars are neutron stars, the most compact star known, that spin up to 700 times per second. This result comes from the synergic work of two international collaborations, TRAPUM and MeerTIME.

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Famous fast radio burst FRB20180916B just barely lets itself be captured

April 15, 2021

Two international teams of astronomers have narrowed-down the origin of the flashes produced in the fast radio burst FRB20180916B by examining them with the highest time resolution and at the lowest possible frequencies. These studies, using the Effelsberg 100-m telescope within the EVN network and the European LOFAR telescope network, have been published in Nature Astronomy and in The Astrophysical Journal Letters (JIVE Press Release, April 15, 2021).

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A Spiral Galaxy with a Huge Magnetic Field

July 21, 2020

New cosmic magnetic field structures discovered in the galaxy NGC 4217

Superbubbles, giant loops and X-shaped magnetic field structures – this galaxy boasts a veritable wealth of shapes. How such structures are formed is a mystery. Some clues are provided by a new study led by Yelena Stein within the framework of the CHANG-ES project (“Continuum HAlos in Nearby Galaxies -- an EVLA Survey”). For a comprehensive image of the magnetic field structures, the researchers combined different methods that enabled them to visualise the ordered and chaotic magnetic fields of the galaxy both along the line of sight and perpendicular to it.

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Confirming Einstein’s Most Fortunate Thought

June 10, 2020

Radio Astronomers use a Dance of Three Exotic Stars to Test the Universality of Free Fall

An international research team including astronomers from the Max Planck Institute for Radio Astronomy (MPIfR) in Bonn determined with extremely high precision that gravity causes neutron stars and white dwarf stars to fall with equal accelerations. They did this by precisely tracking the motion of pulsar PSR J0337+1715, a neutron star that is a member of an unusual triple star system. Their findings – achieved by a new rigorous method and a combination of radio telescope data with latest insight from gravitational wave detectors – provide the strongest test ever of one of the most fundamental predictions of general relativity: that gravity attracts all objects with the same acceleration, without regard for their composition, density or the strength of their own gravitational field.

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Globular cluster billowing in the Galactic wind

March 02, 2020

Investigation of pulsars in 47 Tuc provides constraints on the magnetic field in the halo of the Milky Way

The Galactic magnetic field plays an important role in the evolution of our Galaxy, but its small-scale behaviour is still poorly known. It is also unknown whether it permeates the halo of the Galaxy or not. By using observations of pulsars in the halo globular cluster 47 Tuc, an international research team, who started this work at University of Milano Bicocca and INAF-Astronomical Observatory of Cagliari, could probe the Galactic magnetic field at scales of a few light years for the first time. They discovered an unexpected strong magnetic field in the direction of the cluster. This magnetic field points perpendicularly to the Galactic disk and could be explained by an interaction with the Galactic wind. This is a magnetized outflow that extends from the Galactic disk into the surrounding halo and its existence has never been proven before.

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Fast rotating white dwarf drags its space-time in a cosmic dance

January 30, 2020

How astronomers used Einstein’s theory of general relativity to estimate the rotation of a white dwarf in a binary star system

According to Einstein's general relativity, the rotation of a massive object produces a dragging of space-time in its vicinity. This effect has been measured, in the case of the Earth’s rotation, with satellite experiments. With the help of a radio pulsar, an international team of scientists (with important contributions from scientists at the Max Planck Institute for Radio Astronomy in Bonn, Germany) were able to detect the swirling of the space-time around its fast-rotating white dwarf-companion star, and thus confirm the theory behind the formation of this unique binary star system.

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A Repeating Fast Radio Burst from a Spiral Galaxy

January 06, 2020

Localisation of a new, recurring source of radio flashes deepens the mystery of their origins

The Effelsberg 100-m radio telescope participated in the European VLBI Network (EVN) to observe a repeating Fast Radio Burst (FRB) and helped to pinpoint the FRB to a spiral galaxy similar to our own. Crucial to this work was the sensitivity of the Effelsberg telescope and its flexible pulsar instrument that aided the quick radio localisation. This FRB is the closest to Earth ever localised and was found in a radically different environment to previous studies. The discovery, once again, changes researchers’ assumptions on the origins of these mysterious extragalactic events.

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Giant magnetic ropes in the outskirts of a spiral galaxy

November 26, 2019

First detection of regular magnetic field reversals in the halo of NGC 4631

An international consortium led by scientists from the Max Planck Institute for Radio Astronomy in Bonn, Germany, investigated polarized radio emission from the galaxy NGC 4631 at the VLA radio telescope with a broad-band receiver in a number of spectral windows. They detected for the first time a regular magnetic field over scales of several thousands of light years in the halo of NGC 4631. Moreover, they discovered reversals in the large-scale magnetic field, which they call giant magnetic ropes. This discovery will strengthen the impact of large-scale dynamo theories for spiral galaxies. Further, the regular halo fields may be regarded as a link to intergalactic magnetic fields and will help to understand their origin which is a mystery so far.

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Pulsar emission map thanks to Einstein

September 05, 2019

Radio emission from a neutron star’s magnetic pole revealed by general relativity

Pulsars in binary systems are affected by relativistic effects, causing the spin axes of each pulsar to change their direction with time. A research team led by Gregory Desvignes from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has used radio observations of the source PSR J1906+0746 to reconstruct the polarised emission over the pulsar’s magnetic pole and to predict the disappearance of the detectable emission by 2028. Observations of this system confirm the validity of a 50-year old model that relates the pulsar’s radiation to its geometry. The researchers are also able to precisely measure the rate of change in spin direction and find an excellent agreement with the predictions of Einstein’s general theory of relativity.

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A peek at the birth of the universe

July 24, 2019

Study on new radio telescope in South Africa

The Square Kilometre Array (SKA) is set to become the largest radio telescope on Earth. Scientists of Bielefeld University and the Max Planck Institute for Radio Astronomy (MPIfR) with international partners have now examined the SKA-MPG telescope—a prototype for the part of the SKA that receives signals in the mid-frequency range. The study, published in the journal ‘Monthly Notices of the Royal Astronomical Society’, shows that the telescope, jointly developed by the MPIfR and MT-Mechatronics GmbH, is not only a prototype to test the SKA design, but can also be used on its own to provide insights into the origin of the universe.

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Why lightning often strikes twice: Study reveals needle-like structures in positively charged lightning leaders

April 17, 2019

In contrast to popular belief, lightning often does strike twice, but the reason why a lightning channel is 'reused' has remained a mystery. Now, an international research team including scientists from the MPIfR has used the LOFAR radio telescope to study the development of lightning flashes in unprecedented detail. The results were published on 18 April in the science journal Nature.

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Astronomers Capture First Image of a Black Hole

April 10, 2019

MPIfR and IRAM contribute to groundbreaking observations of the gargantuan black hole at the heart of distant galaxy Messier 87

The Event Horizon Telescope (EHT) — a planet-scale array of eight ground-based radio telescopes forged through international collaboration — was set up to capture the first images of a black hole. Today, in coordinated press conferences across the globe, EHT researchers including scientists from both, the Max-Planck-Institut für Radioastronomie (MPIfR) in Bonn, Germany, and the Institut de Radioastronomie Millimétrique (IRAM) reveal that they have succeeded, unveiling the first direct visual evidence of a black hole.

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Hundreds of Thousands of New Galaxies

February 19, 2019

Astronomers publish new sky map detecting a vast number of previously unknown galaxies

An international team of more than 200 astronomers from 18 countries including scientists from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has published the first phase of a major new radio sky survey at unprecedented sensitivity using the Low Frequency Array (LOFAR) telescope. The survey reveals hundreds of thousands of previously undetected galaxies, shedding new light on many research areas including the physics of black holes and how clusters of galaxies evolve.

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Weighing planets and asteroids

October 22, 2018

Pulsar observations enable mass estimates for Ceres and other solar system objects

A team of scientists from the “International Pulsar Timing Array″ consortium, led by researchers from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has used pulsar timing data to measure the masses of the dwarf-planet Ceres and other asteroids. The result for the mass of Ceres is 1.3% of the mass of the Earth’s moon. The team has also measured the masses of the major planets of the solar system with much improved precision than a past study and demonstrated how pulsar-timing data can be used to explore unknown massive objects orbiting the Sun.

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A New Experiment to Understand Dark Matter

June 14, 2018

Do we have to change our view on how Dark Matter interacts with standard matter?

Is dark matter a source of a yet unknown force in addition to gravity? The mysterious dark matter is little understood and trying to understand its properties is an important challenge in modern physics and astrophysics. Researchers at the Max Planck Institute for Radio Astronomy in Bonn, Germany, have proposed a new experiment that makes use of super-dense stars to learn more about the interaction of dark matter with standard matter. This experiment already provides some improvement in constraining dark matter properties, but even more progress is promised by explorations in the centre of our Milky Way that are underway.

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Can we tell black holes apart?

April 16, 2018

The current ability to test theories of gravity with black hole shadows

Astrophysicists at Frankfurt, the Max Planck Institute for Radio Astronomy in Bonn, and Nijmegen, collaborating in the project BlackHoleCam, answer this question by computing the first images of feeding non-Einsteinian black holes: it is presently hard to tell them apart from standard black holes.

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Einstein@Home discovers first millisecond pulsar visible only in gamma rays

February 28, 2018

Distributed volunteer computing project finds two rapidly rotating neutron stars in data from Fermi gamma-ray space telescope

The distributed computing project Einstein@Home aggregates the computing power donated by tens of thousands of volunteers from across the globe. In a survey of the gamma-ray sky, this computer network has now discovered two previously unknown rapidly rotating neutron stars in data from the Fermi gamma-ray space telescope. While all other such millisecond pulsars have also been observed with radio telescopes, one of the two discoveries is the first millisecond pulsar detectable solely through its pulsed gamma-ray emission. The findings raise hopes of detecting other new millisecond pulsars, e.g., from a predicted large population of such objects towards the center of our Galaxy.

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A Repeating Fast Radio Burst in an Extreme Environment

January 10, 2018

Extragalactic source of energetic radio bursts resides in a strongly magnetized astrophysical region

New detections of highly polarized flashes of radio waves from the repeating fast radio burst FRB121102 have revealed the presence of a strong magnetic field in the source’s local environment. Such strong magnetic fields are rare in astrophysical environments and suggest that the source of the burst is in the vicinity of a massive black hole or within a nebula of unprecedented power.

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The detection of magnetic fields in a galaxy 5 billion light years away

August 25, 2017

Astronomers obtain major clues for solving the origin of cosmic magnetism

Magnetic fields play an important role in the physics of the interstellar medium in galaxies, but they are very difficult to observe at vast distances corresponding to large look-back times in the cosmic history. An international team of astronomers led by Sui Ann Mao from the Max Planck Institute for Radio Astronomy in Bonn, Germany was able to measure the magnetic field in a galaxy beyond the local volume, as seen 4.6 billion light years away at a redshift of 0.439. The galaxy, acting as the lens in the gravitational lensing system CLASS B1152+199, is the most distant galaxy to-date in which a large-scale coherent magnetic field has been observed. This measurement provides new insights into the origin and evolution of magnetic fields in the Universe.

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Giant Magnetic Fields in the Universe

March 22, 2017

The 100-m radio telescope Effelsberg observes magnetic structures with several million light years extent

Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.

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Tune your radio: galaxies sing while forming stars

February 21, 2017

What radio emission tells us about star formation in distant spiral galaxies

A team of astronomers led by Fatemeh Tabatabaei from the Instituto de Astrofisica de Canarias (IAC), including scientists from two Max Planck institutes (MPIfR, Bonn and MPIA, Heidelberg), has measured the radio emission for a large sample of galaxies with the Effelsberg 100-m radio telescope at different wavelengths. These galaxies were selected from the KINGFISH sample previously observed in the infrared with the Herschel satellite. This allows for the first time a comparative study of a total of 52 spiral galaxies. A reliable method could be established to determine the star formation rate exclusively from radio data without including other spectral regimes.

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Home Galaxy of a Fast Radio Burst Identified

January 04, 2017

Astronomers pinpoint radio flashes originating in a far away galaxy

For the first time astronomers have exactly pinpointed the location of a "fast radio burst" - a type of short-duration radio flash of unknown astrophysical origin - and have used this to identify its home galaxy. The galaxy, located over 3 billion light years away, is small, a so-called dwarf galaxy, and very different to our own Milky Way. Also, a persistent, compact radio source is close to the source of the bursts, which provides important insights into its astrophysical origin.

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Home computers discover a record-breaking pulsar-neutron star system

December 08, 2016

International science team finds most massive double neutron star system with distributed volunteer computing project Einstein@Home in data from the Arecibo radio telescope

Almost 25,000 light years away, two dead stars, each more massive than our Sun, but only 20 kilometers in diameter, orbit one another in less than five hours. This unusual pair of extreme objects, known as neutron stars, was discovered by an international team of scientists – including researchers from the Max Planck Institute for Gravitational Physics and the Max Planck Institute for Radio Astronomy – and by volunteers from the distributed computing project Einstein@Home. Their find is the latest addition to a short list of only 14 known similar binary systems, and it also is the most massive of those. Double neutron star systems are important cosmic laboratories that enable some of the most precise tests of Einstein’s theory of general relativity. They also play an important role as potential gravitational-wave sources for the LIGO detectors.

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Smoking Gun Uncovering Secret of Cosmic Bullets

March 02, 2016

LOFAR radio telescope catches signals from disintegrating cosmic particles, revealing their nature

LOFAR, the low-frequency array radio telescope, normally receives weak radio waves from the distant universe. But now and then an ultra-short, bright radio pulse is observed somewhere in between AM and FM radio frequencies. This radio blast would appear as a short cracking sound in your car radio. While usually ignored, this radio signal is actually the last SOS of an elementary particle entering the Earth atmosphere at almost the speed of light. The particles were fired off by a cosmic accelerator Millions of year ago. An international team of astronomers including a number of scientists from the German Long Wavelength consortium (GLOW) have now unraveled the radio code of these intruders to determine their nature and constrain their origin.

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Mysterious cosmic radio bursts found to repeat

March 02, 2016

New observations provide strong evidence for multiple populations of Fast Radio Bursts

An international research team including astronomers from the Max Planck Institute for Radio Astronomy (MPIfR) in Bonn, Germany, has discovered the first source of repeating bursts of radio waves which is located well beyond our Milky Way galaxy. Fast radio bursts, lasting just a few thousandths of a second, have puzzled scientists since they were first reported nearly a decade ago. The findings indicate that these “fast radio bursts” come from an extremely powerful object which occasionally produces multiple bursts in under a minute.

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Putting the Universe on the Scales

February 24, 2016

Discovery of a Fast Radio Burst reveals 'missing matter' in the Universe

An international research team including scientists from the Max Planck Institute for Radio Astronomy in Bonn, Germany used a combination of radio and optical telescopes to identify the precise location of a fast radio burst in a distant galaxy, allowing them to conduct a unique census of the Universe’s matter content.

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Listening to the Extragalactic Radio

October 13, 2015

Astronomers Probe Outer Regions of Other Galaxies at Low Frequencies

CHANG-ES, the “Continuum Halos in Nearby Galaxies, an EVLA Survey” project, brings together scientists from all over the globe in order to investigate the occurrence and origin of radio halos, to probe the disk-halo interface, and to study in-disk emission as well as their magnetic fields and the cosmic rays illuminating these fields. The goal is to understand connections between radio halos and the host disk and its environment.

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Twisted magnetic loop in the Giraffe galaxy IC 342

June 18, 2015

Magnetic-Field Discovery Gives Clues to Galaxy-Formation Processes

Magnetic fields exist everywhere in the Universe, but there is still little idea how important they are for the evolution of cosmic objects. Radio waves are an ideal means to measure magnetic fields in galaxies. In a long-standing effort, Rainer Beck from the Max Planck Institute for Radio Astronomy (MPIfR) in Bonn, Germany, gathered a huge data set of the nearby galaxy IC 342 from observations with two of the world’s largest radio telescopes, NRAO’s Very Large Array and the 100-m radio telescope of the MPIfR, in four different wavelength bands, from 2.8 cm to 21 cm. An ordered magnetic field mostly aligned along the optical spiral arms was discovered. The discovery helps to explain how galactic spiral arms are formed. The same study also shows how gas can be funneled inward toward the center of IC 342. more

Swirling Electrons in the Whirlpool Galaxy

August 20, 2014

Cosmic particles and magnetic fields in the galaxy M51 observed with the LOFAR radio telescope

The whirlpool galaxy Messier 51 (M51) is seen from a distance of approximately 30 million light years. This galaxy appears almost face-on and displays a beautiful system of spiral arms.
A European team of astronomers was able to observe M51 with the International LOFAR Telescope in the frequency range 115-175 MHz, just above the normal commercial FM radio frequency band of 88-108 MHz. The team obtained the most sensitive image of any galaxy at frequencies below 1 GHz so far. With LOFAR's high sensitivity, the disk of M51 in the radio regime could be traced much further out than before. The astronomers detected cosmic electrons and magnetic fields 40,000 light years away from the center of M51.

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Radio-burst discovery deepens astrophysics mystery

July 10, 2014

Newly detected short radio pulse appears to come from far beyond our galaxy

The discovery of a split-second burst of radio waves using the Arecibo radio telescope in Puerto Rico provides important new evidence of mysterious pulses that appear to come from deep in outer space. The findings by an international team of astronomers led by Laura Spitler from the Max Planck Institute for Radio Astronomy in Bonn, Germany are published on July 10 in the online issue of The Astrophysical Journal. They mark the first time that a so-called "fast radio burst" has been detected in the Northern hemisphere of the sky.

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Trio of supermassive black holes shake space-time

June 25, 2014

Tight system of black holes in a distant galaxy

Astronomers have discovered three closely orbiting supermassive black holes in a galaxy more than 4 billion light years away. This is the tightest trio of black holes known to date and is remarkable since most galaxies have just one black hole, usually with a mass between 1 million to 10 billion times that of the Sun, at their centre. The discovery suggests that such closely packed supermassive black holes are far more common than previously thought.

An international research team, including Hans-Rainer Klöckner from the Max Planck Institute for Radio Astronomy in Bonn, Germany, performed VLBI (Very Long Baseline Interferometry) observations with radio telescopes at a number of frequencies to discover the inner two black holes of the triple system. The VLBI technique combines the signals from large radio antennas separated by up to 10. 000 kilometres to see details 50 times finer than that possible with the Hubble Space Telescope. In this project the Effelsberg 100m radio telescope took part in European VLBI network (EVN) observations covering two radio frequencies.

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An Exotic Millisecond Pulsar Trio

January 06, 2014

Stellar astrophysicists probe new territory with the discovery of a neutron star orbited by two white dwarfs
Millisecond pulsars are old neutron stars, with rotational frequencies of several hundred revolutions per second. Previous theoretical studies have explained their origin via mass transfer in binary systems. However, the first discovery of a millisecond pulsar in a triple system is quite a surprise and challenges current consensus. The astrophysicist Thomas Tauris from the Max Planck Institute for Radio Astronomy and the Argelander Institute for Astronomy in Bonn, has developed a semi-analytical model, jointly with Ed van den Heuvel from the University of Amsterdam, which can resolve the puzzling formation of this exotic triple system. Through theoretical calculations and stability analysis on the base of stellar evolution, they have demonstrated a plausible theoretical model which brings new insight to our knowledge of stellar interactions in multiple star systems. Their study can also help explain an increasing number of observed binary millisecond pulsars which seem to require a triple system origin. more

The Manifold Path to Millisecond Pulsars

December 16, 2013

New pulsar systems suggest that Nature is far more creative than previously thought

Two astronomers from Bonn have proposed a new path for the formation of a newly discovered class of millisecond pulsars with similar orbital periods and eccentricities. In the scenario of Paulo Freire and Thomas Tauris, a massive white dwarf star accretes matter and angular momentum from a normal companion star and grows beyond the critical Chandrasekhar mass limit. However, it does not collapse immediately into a neutron star because it is rotating very fast and is thus sustained by centrifugal forces. After the mass transfer ceases, this massive white dwarf loses rotational energy and eventually collapses directly into a millisecond pulsar, without the need for further accretion. The associated instantaneous release of gravitational binding energy is expected to produce the characteristic eccentricities observed in such systems. The new hypothesis makes several testable predictions about this recently discovered sub-class of millisecond pulsars. If confirmed, it opens up new avenues of research into the physics of stars, in particular the momentum kicks and mass loss associated with accretion induced collapse of massive white dwarfs.

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Two Galaxies for the Price of One

December 03, 2013

Surprising Image Reveals New Tool to Study Magnetic Fields of Galaxies

An international group of astronomers, including Marita Krause and Rainer Beck from Max-Planck-Institut für Radioastronomie (MPIfR) in Bonn, has found a surprising and useful new probe of galactic magnetic fields. While studying gas halos around nearby galaxies, they were surprised when detailed studies with the Karl G. Jansky Very Large Array (VLA) showed that one of their subjects is not a single galaxy, but rather two, nearly perfectly superimposed on the sky to masquerade as one. The discovery allowed them to use the alignment to learn otherwise-unobtainable facts about the nearer galaxy.

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Home Computers discover γ-ray Pulsars

November 26, 2013

Einstein@Home volunteers find four cosmic lighthouses in data from NASA's Fermi Gamma-ray Space Telescope

The combination of globally distributed computing power and innovative analysis methods proves to be a recipe for success in the search for new pulsars. Scientists from the Max Planck Institutes for Gravitational Physics and Radio Astronomy together with international colleagues have now discovered four γ-ray pulsars in data from the Fermi space telescope. The breakthrough came using the distributed computing project Einstein@Home, which connects more than 200,000 computers from 40,000 participants around the world to a global supercomputer. The discoveries include volunteers from Australia, Canada, France, Germany, Japan, and the USA.

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Neutron stars in the computer cloud

August 29, 2013

Einstein@Home discovers 24 new pulsars in archival data

The combined computing power of 200,000 private PCs helps astronomers take an inventory of the Milky Way. The Einstein@Home project connects home and office PCs of volunteers from around the world to a global supercomputer. Using this computer cloud, an international team lead by scientists from the Max Planck Institutes for Gravitational Physics and for Radio Astronomy analysed archival data from the CSIRO Parkes radio telescope in Australia. Using new search methods, the global computer network discovered 24 pulsars – extraordinary stellar remnants with extreme physical properties. These can be used as testbeds for Einstein's general theory of relativity and could help to complete our picture of the pulsar population.

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A magnetar at the heart of our Milky Way

August 14, 2013

Radio astronomers use pulsar with strong magnetic field to investigate supermassive black hole

Astronomers have discovered a magnetar at the centre of our Milky Way. This pulsar has an extremely strong magnetic field and enables researchers to investigate the direct vicinity of the black hole at the heart of the galaxy. An international team of scientists headed by the Max Planck Institute for Radio Astronomy in Bonn have, for the first time, measured the strength of the magnetic field around this central source and were able to show that the latter is fed by magnetic fields. These control the inflow of mass into the black hole, also explaining the x-ray emissions of this gravity trap.

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Flashes in the sky

July 04, 2013

Cosmic radio bursts point to cataclysmic origins in the distant universe

An international team of researchers including scientists from the Max Planck Institute for Radio Astronomy in Bonn have detected burst of radio waves that appear to have originated billions of light years away - when the Universe was just 6 to 9 billion years old. The researchers are still baffled about the origins of these emissions. In the future, they intend to use these flashes to probe the intergalactic space. more

A heavyweight for Einstein

April 25, 2013

Probing gravity where no one has done it before

An international research team led by astronomers from the Max Planck Institute for Radio Astronomy (Bonn, Germany) used a collection of large radio and optical telescopes to investigate PSR J0348+0432, a newly discovered pulsar, and its white dwarf companion. The observations revealed a system with unusual properties: weighing twice as much as the Sun, making it the most massive neutron star measured to date. This, in combination with its short orbital period of only 2.5 hours, provides insight into binary stellar evolution and makes this system a strong emitter of gravitational radiation. The energy loss through this radiation has already been detected in the radio observations of the pulsar, making it a laboratory for General Relativity in extreme conditions not accessible before. The findings are in excellent agreement with Einstein's theory.

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A Janus-faced neutron star

January 24, 2013

Chameleon pulsar baffles astronomers

An international team - led by Dutch astronomers (SRON, NOVA and ASTRON) - has made a tantalizing discovery about the way pulsars emit radiation. The emission of X-rays and radio waves by these pulsating neutron stars is able to change dramatically in seconds, simultaneously, in a way that cannot be explained with current theory. It suggests a quick change of the entire magnetosphere. In their research the team combined observations from the X-ray space telescope XMM-Newton and the radio telescope LOFAR (among others).

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Supermassive black hole inflates giant bubble

October 29, 2012

Observations of the Radio Galaxy Messier 87 with the European low-frequency LOFAR Telescope

Using the brand-new radio telescope LOFAR, an international team of astronomers led by the Max Planck Institute for Astrophysics have taken one of the best images ever of giant bubbles produced by a super-massive black hole. The picture - taken in a frequency range normally used for airplane communication - shows what looks like a giant balloon filled with plasma and magnetic fields. This bubble, much exceeding the size of the radio galaxy M87 in the Virgo cluster, was slowly inflated by one of the most massive black holes in our cosmic neighbourhood, located in the centre of M87. more

A black widow's Tango Mortale in gamma-ray light!

October 25, 2012

Max Planck scientists discover record-breaking millisecond pulsar with new analysis method

Pulsars are the compact remnants from explosions of massive stars. Some of them spin around their own axis hundreds of times per second, emitting beams of radiation into space. Until now, they could only be found through their pulsed radio emissions. Now, scientists at the Max Planck Institute for Gravitational Physics (Albert Einstein Institute/AEI) in Hanover assisted by the Max Planck Institute for Radio Astronomy have discovered a millisecond pulsar solely via its pulsed gamma radiation. A new data analysis method developed by the AEI was crucial for the success. The pulsar is accompanied by an unusual sub-stellar partner, which it is vaporizing, hence the name ``black widow''

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A pulsar with a tremendous hiccup!

July 24, 2012

Max Planck scientists discover a young and energetic neutron star with unusually irregular rotation

Pulsars are superlative cosmic beacons. These compact neutron stars rotate about their axes many times per second, emitting radio waves and gamma radiation into space. Using ingenious data analysis methods, researchers from the Max Planck Institutes for Gravitational Physics and for Radio Astronomy, in an international collaboration, dug a very special gamma-ray pulsar out of data from the Fermi Gamma-ray Space Telescope. The pulsar J1838−0537 is radio-quiet, very young, and, during the observation period, experienced the strongest rotation glitch ever observed for a gamma-ray-only pulsar.

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The discovery of deceleration

February 02, 2012

Stellar Astrophysics helps to explain the behaviour of fast rotating neutron stars in binary systems

Pulsars are among the most exotic celestial bodies known. They have diameters of about 20 kilometres, but at the same time roughly the mass of our sun. A sugar-cube sized piece of its ultra-compact matter on the Earth would weigh hundreds of millions of tons. A sub-class of them, known as millisecond pulsars, spin up to several hundred times per second around their own axes. Previous studies reached the paradoxical conclusion that some millisecond pulsars are older than the universe itself. The astrophysicist Thomas Tauris from the Max Planck Institute for Radio Astronomy and the Argelander-Institut für Astronomie in Bonn could resolve this paradox by computer simulations.

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Millisecond pulsar in spin mode

November 03, 2011

The gamma radiation of a rapidly rotating neutron star casts doubt on the models of the origin of such objects

Astronomers have tracked down the first gamma-ray pulsar in a globular cluster of stars. It is around 27,000 light years away and thus also holds the distance record in this class of objects. Moreover, its high luminosity indicates that J1823-3021A is the youngest millisecond pulsar found to date, and that its magnetic field is much stronger than theoretically predicted. This therefore suggests the existence of a new population of such extreme objects. The discovery was made by Paulo Freire and an international team of scientists from the Max Planck Institute for Radio Astronomy in Bonn. The researchers evaluated data from the Fermi space telescope.

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Nine new gamma pulsars

November 03, 2011

Discoveries in Fermi telescope data thanks to method used in gravitational wave astronomy

Pulsars are the lighthouses of the universe. These compact and fast-rotating neutron stars flash many times per second in the radio or gamma-ray band. Pure gamma-ray pulsars are extremely difficult to find despite their high energy because they radiate very few photons per unit of time. Using an improved analysis algorithm, Max Planck scientists and international partners have now discovered a number of previously unknown gamma-ray pulsars with low luminosity in data from the Fermi satellite. These pulsars had been missed using conventional methods. The number of known gamma-ray pulsars has thus grown to over 100.

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The diamond planet

August 30, 2011

Radio wave observations show the transformation of a galaxy into a millisecond pulsar and its companion planet

A star that changes into a diamond planet? What sounds like science fiction is apparently reality. The discovery was made by an international team of scientists from Australia, Italy, Great Britain, the USA and Germany, including Michael Kramer from the Max Planck Institute for Radio Astronomy in Bonn. The researchers found the diamond planet with the help of the 64-metre Parkes radio telescope in Australia. The planet apparently orbits around an unusual, very dense star, a pulsar.

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An atlas of the Milky Way

August 30, 2011

Sino-German research group draws a new map at the Urumqi radio telescope and discovers two supernova remnants

It may not be much use to hitchhikers through the galaxy, but it is extremely valuable to astronomers: the new radio atlas of the Milky Way. After almost ten years of work, researchers at the Max Planck Society and the Chinese Academy of Sciences have completed their investigation into the polarised radio emission in the galactic plane. The atlas is based on observations undertaken with the 25-metre radio telescope in the Chinese city of Urumqi and shows an area of 2,200 square degrees of the sky.

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Weighing the Planets - from Mercury to Saturn

August 24, 2010

Pulsar timing observations allow a new way to estimate planet masses

An international research team led by David Champion, now at Max Planck Institute for Radio Astronomy in Bonn, with researchers from Australia, Germany, the U.S., UK and Canada has come up with a new way to weigh the planets in our Solar System, using radio signals from pulsars. Data from a set of four pulsars have been used to weigh Mercury, Venus, Mars, Jupiter and Saturn with their moons and rings. The new measurement technique is sensitive to just 0.003% of the mass of the Earth, and one ten-millionth of Jupiter's mass (corresponding to a mass difference of two hundred thousand million million tonnes).

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Einstein@Home "citizen scientists" discover new pulsar!

August 10, 2010

Einstein@Home "citizen scientists'' in the U.S.A. and Germany discover a new pulsar in Arecibo telescope data

Idle computers are the astronomers' playground: Three citizen scientists - a German and an American couple - have discovered a new radio pulsar hidden in data gathered by the Arecibo Observatory. This is the first deep-space discovery by Einstein@Home, which uses donated time from the home and office computers of 250,000 volunteers from 192 different countries. The citizens credited with the discovery are Chris and Helen Colvin, of Ames, Iowa and Daniel Gebhardt, of Universität Mainz, Musikinformatik, Germany. Their computers, along with 500,000 others from around the world, analyze data for Einstein@Home (on average, donors contribute about two computers each).

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Astronomers making good time

June 24, 2010

Correcting for rotational instabilities of pulsars, the most precise clocks in the Universe

An international team of astronomers, including Michael Kramer from the Max-Planck-Institut für Radioastronomie (Bonn, Germany) has studied the behaviour of natural cosmic clocks and discovered a way to potentially turn them into the best time keepers in the Universe. The scientists made their breakthrough using decade-long observations from the 76-m Lovell radio telescope at the University of Manchester's Jodrell Bank Observatory to track the radio signals of an extreme type of star known as a pulsars. This new understanding of pulsar spin-down could improve the chances to use the fastest spinning pulsars in order to make the first direct detection of ripples, known as gravitational waves, in the fabric of space time.

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Highlights — Some exciting recent scientific results from our group