Most Black Holes Spin Rapidly. This one… Doesn’t

This is the first image of Sgr A*, the supermassive black hole at the centre of our galaxy. It’s the first direct visual evidence of the presence of this black hole. It was captured by the Event Horizon Telescope (EHT), an array which linked together eight existing radio observatories across the planet to form a single “Earth-sized” virtual telescope. The telescope is named after the event horizon, the boundary of the black hole beyond which no light can escape.   Although we cannot see the event horizon itself, because it cannot emit light, glowing gas orbiting around the black hole reveals a telltale signature: a dark central region (called a shadow) surrounded by a bright ring-like structure. The new view captures light bent by the powerful gravity of the black hole, which is four million times more massive than our Sun. The image of the Sgr A* black hole is an average of the different images the EHT Collaboration has extracted from its 2017 observations.  In addition to other facilities, the EHT network of radio observatories that made this image possible includes the Atacama Large Millimeter/submillimeter Array (ALMA) and the Atacama Pathfinder EXperiment (APEX) in the Atacama Desert in Chile, co-owned and co-operated by ESO is a partner on behalf of its member states in Europe.
A Chandra X-ray Observatory view of the supermassive black hole at the heart of quasar H1821+643. Courtesy NASA/CXC/Univ. of Cambridge/J. Sisk-Reynés et al.
A Chandra X-ray Observatory view of the supermassive black hole at the heart of quasar H1821+643. Courtesy NASA/CXC/Univ. of Cambridge/J. Sisk-Reynés et al.

Black holes. They used to be theoretical, up until the first one was found and confirmed back in the late 20th Century. Now, astronomers find them all over the place. We even have direct radio images of two black holes: one in M87 and Sagittarius A* in the center of our galaxy. So, what do we know about them? A lot. But, there’s more to find out. A team of astronomers using Chandra X-ray Observatory data has made a startling discovery about a central supermassive black hole in a quasar embedded in a distant galaxy cluster. What they found provides clues to the origin and evolution of supermassive black holes.

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Astronomers Finally Catch a Nova Detonating on a White Dwarf as it's Happening

Artist impression of an exploding White Dwarf. Credit: University of Tubigen.

On July 7, 2020, the X-ray instrument eROSITA captured an astronomical event that – until then – had only been theorized and never seen. It saw the detonation of a nova on a white dwarf star, which produced a so-called fireball explosion of X-rays.

“It was to some extent a fortunate coincidence, really,” said Ole König from Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), who led the team of scientists who have published a new paper on the discovery. “These X-ray flashes last only a few hours and are almost impossible to predict, but the observational instrument must be pointed directly at the explosion at exactly the right time.”

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A Pulsar is Blasting out Jets of Matter and Antimatter

This image from NASA's Chandra X-ray Observatory and ground-based optical telescopes shows an extremely long beam, or filament, of matter and antimatter extending from a relatively tiny pulsar, as reported in our latest press release. With its tremendous scale, this beam may help explain the surprisingly large numbers of positrons, the antimatter counterparts to electrons, scientists have detected throughout the Milky Way galaxy. Image Credit: X-ray: NASA/CXC/Stanford Univ./M. de Vries; Optical: NSF/AURA/Gemini Consortium

Why is there so much antimatter in the Universe? Ordinary matter is far more plentiful than antimatter, but scientists keep detecting more and more antimatter in the form of positrons. More positrons reach Earth than standard models predict. Where do they come from?

Scientists think pulsars are one source, and a new study strengthens that idea.

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The First Image From NASA’s new X-ray Observatory

This image of the supernova remnant Cassiopeia A combines some of the first X-ray data collected by NASA’s Imaging X-ray Polarimetry Explorer, shown in magenta, with high-energy X-ray data from NASA’s Chandra X-Ray Observatory, in blue. Credits: NASA/CXC/SAO/IXPE

It’s first light for one of the newest space observatories! The Imaging X-Ray Polarimetry Explorer team has released their first image, taken after a month-long commissioning phase for the spacecraft. And it’s a beauty.

IXPE looked at a favorite target among space observatories, the supernova remnant Cassiopeia A. While x-rays are invisible to human eyes, the amount of magenta color in this image corresponds to the intensity of X-ray light observed. Needless to say, it’s intense with high energy x-rays.  

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NASA Launches a New X-ray Observatory

A SpaceX Falcon 9 rocket launches with NASA’s Imaging X-ray Polarimetry Explorer (IXPE) spacecraft onboard from Launch Complex 39A, Thursday, Dec. 9, 2021, at NASA’s Kennedy Space Center in Florida. The IXPE spacecraft is the first satellite dedicated to measuring the polarization of X-rays from a variety of cosmic sources, such as black holes and neutron stars. Launch occurred at 1 a.m. EST. Credits: NASA/Joel Kowsky

A new mission has launched to study some the most intriguing secrets of the universe. No, not THAT spacecraft (JWST is scheduled for launch on December 22). Another new and exciting mission is called Imaging X-ray Polarimetry Explorer (IXPE) and it will allow scientists to explore the hidden details of some of the most extreme and high-energy objects in the cosmos, such as black holes, neutron stars, pulsars and dozens of other objects.

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A Black Hole Emitted a Flare Away From us, but its Intense Gravity Redirected the Blast Back in our Direction

Artist's impression of a black hole, as indicated by its bright accretion disk. Credit: NASA

In 1916, Albert Einstein put the finishing touches on his Theory of General Relativity, a journey that began in 1905 with his attempts to reconcile Newton’s own theories of gravitation with the laws of electromagnetism. Once complete, Einstein’s theory provided a unified description of gravity as a geometric property of the cosmos, where massive objects alter the curvature of spacetime, affecting everything around them.

What’s more, Einstein’s field equations predicted the existence of black holes, objects so massive that even light cannot escape their surfaces. GR also predicts that black holes will bend light in their vicinity, an effect that can be used by astronomers to observe more distant objects. Relying on this technique, an international team of scientists made an unprecedented feat by observing light caused by an X-ray flare that took place behind a black hole.

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New Mosaic Shows the Galactic Core From Opposite Sides of the Electromagnetic Spectrum

Credit: X-ray: NASA/CXC/UMass/Q.D. Wang; Radio: NRF/SARAO/MeerKAT)

The core of the Milky Way Galaxy (aka. Galactic Center), the region around which the rest of the galaxy revolves, is a strange and mysterious place. It is here that the Supermassive Black Hole (SMBH) that powers the compact radio source known as Sagittarius A* is located. It is also the most compact region in the galaxy, with an estimated 10 million stars within 3.26 light-years of the Galactic Center.

Using data from Chandra X-ray Observatory and the MeerKAT radio telescope, NASA and the National Research Foundation (NSF) of South Africa created a mosaic of the center of the Milky Way. Combining images taken in the x-ray and radio wavelengths, the resulting panoramic image manages to capture the filaments of super-heated gas and magnetic fields that (when visualized) shows the complex web of energy at the center of our galaxy.

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If You Could See in X-rays, This is What the Universe Would Look Like

The energetic Universe as seen with the eROSITA X-ray telescope. Credit: Jeremy Sanders, Hermann Brunner and the eSASS team (MPE); Eugene Churazov, Marat Gilfanov (on behalf of IKI).

X-ray astronomy helps scientists study neutron stars, binary star systems, and supernova remnants, and even helps detect black holes. But even if human eyes had the ability to see X-rays, we couldn’t just look up at the night sky and see these amazing objects since Earth’s atmosphere absorbs and blocks X-rays. So, thank goodness for space telescopes!  And the newest X-ray instrument in space has just produced a breathtaking view of the Universe, and is the deepest X-ray view of the sky we’ve ever seen.  

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Astronomers Have Recorded the Biggest Explosion Ever Seen in the Universe

Hundreds of millions of light years away, a supermassive black hole sits in the center of a galaxy cluster named Ophiuchus. Though black holes are renowned for sucking in surrounding material, they sometimes expel material in jets. This black hole is the site of an almost unimaginably powerful explosion, created when an enormous amount of material was expelled.

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Astronomers Find a Supermassive Black Hole That’s Feasting on a Regular Schedule, Every 9 Hours

The supermassive black hole at the heart of galaxy GSN 069 has a unique, regular feeding schedule. Every 9 hours it flares with x-rays as it consumes matter. Image Credit: X-ray: NASA/CXO/CSIC-INTA/G.Miniutti et al.; Optical: DSS.

Astronomers have found a supermassive black hole (SMBH) with an unusually regular feeding schedule. The behemoth is an active galactic nucleus (AGN) at the heart of the Seyfert 2 galaxy GSN 069. The AGN is about 250 million light years from Earth, and contains about 400,000 times the mass of the Sun.

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