Red giant and neutron star interaction

Donor star breathes life into zombie companion

ESA’s Integral space observatory has witnessed a rare event: the moment that winds emitted by a swollen red giant star revived its slow-spinning companion, the core of a dead star, bringing it back to life in a flash of X-rays. The X-ray flare was first detected by Integral on 13 August 2017 from an unknown source in the direction of the crowded centre of our Milky Way. The sudden detection triggered a slew of follow-up observations in the following weeks to pin down the culprit. The observations revealed a strongly magnetised and slowly rotating neutron star that had likely just begun to feed on material from a neighbouring red giant star.

Stars the mass of our Sun, and up to eight times more massive, evolve into red giants towards the end of their lives. Their outer layers puff up and expand millions of kilometres, their dusty, gassy shells blown away from the central star in relatively slow winds up to few hundreds of km/s.

Stellar evolution Even larger stars, up to 25–30 times more massive than the Sun, race through their fuel and explode in a supernova, sometimes leaving behind a spinning stellar corpse with a strong magnetic field, known as a neutron star. This tiny core packs the mass of nearly one and half Suns into a sphere only 10 km across, making them some of the densest celestial objects known. It is not uncommon to find stars paired together, but the new system of a neutron star and red giant is a particularly rare breed known as a ‘symbiotic X-ray binary’, with no more than 10 known. “Integral caught a unique moment in the birth of a rare binary system,” says Enrico Bozzo from University of Geneva and lead author of the paper that describes the discovery. “The red giant released a sufficiently dense slow wind to feed its neutron star companion, giving rise to high-energy emission from the dead stellar core for the first time.”

The pairing is certainly peculiar. ESA’s XMM-Newton and NASA’s NuSTAR space telescopes showed that the neutron star spins almost every two hours – very slow compared with other neutron stars, which can spin up to many times per second. Then, the first measurement of the magnetic field of such a neutron star revealed it to be surprisingly strong. A strong magnetic field typically points to a young neutron star – the magnetic field is thought to fade over time – while a red giant is much older, making it a bizarre couple to have grown up together. “These objects are puzzling,” says Enrico. “It might be that either the neutron star magnetic field does not decay substantially with time after all, or the neutron star actually formed later in the history of the binary system. That would mean it collapsed from a white dwarf into a neutron star as a result of feeding off the red giant over a long time, rather than becoming a neutron star as a result of a more traditional supernova explosion of a short-lived massive star.” With a young neutron star and an old red giant, at some point the winds travelling from the puffed-up giant will begin to rain on to the smaller star, slowing its spin and emitting X-rays. “We haven’t seen this object before in the past 15 years of our observations with Integral, so we believe we saw the X-rays turning on for the first time,” says Erik Kuulkers, ESA’s Integral project scientist. “We’ll continue to watch how it behaves in case it is just a long ‘burp’ of winds, but so far we haven’t seen any significant changes.”

Notes for Editors “IGR J17329-2731: the birth of a symbiotic X-ray binary,” by E. Bozzo et al is accepted for publication in Astronomy & Astrophysics. The rapid response of the follow-up observations was enabled by the SmartNet community. This included important contributions from ESA’s XMM-Newton and NASA’s NuSTARand Swift space telescopes, and the ground-based Southern Astrophysical Research Telescope, Faulkes Telescopes North and South and the Las Cumbres Observatory. For further information, please contact:

Enrico Bozzo

University of Geneva, Switzerland

Email: enrico.bozzo@unige.ch Erik Kuulkers

ESA Integral project scientist

Email: erik.kuulkers@esa.int Markus Bauer

ESA Science Communication Officer

Tel: +31 71 565 6799

Mob: +31 61 594 3 954

Email: markus.bauer@esa.int </s> An Indian scientist recently discovered 15 repeating radio bursts emitted by a dwarf galaxy after observing it for five hours.

Here's all you need to know about the finding:

1. This discovery was made by Breakthrough Listen postdoctoral researcher Vishal Gajjar, who was detecting extraterrestrials. The dwarf galaxy that gave out these 15 electromagnetic emissions is located at a distance of around 3 million light years from Earth.

2. Breakthrough Listen was launched in 2015 as an initiative to find signs of intelligent life in the universe. As per the hypotheses of the researchers, these emissions could be from an energy source that is being utilised by extraterrestrial civilisations to fuel their spaceships.

"Bursts from this source have never been seen at this high a frequency," said Andrew Siemion, director of the Berkeley SETI Research Centre and a member of the Breakthrough Listen programme.

ALSO READ: Bizarre alien technology spotted in a new UFO sighting in Germany? [VIDEO]

3. "When the recently-detected pulses left their host galaxy, our entire Solar System was just 2 billion years old," said Breakthrough Listen in a statement, referring to the 15 fast radio bursts (FRBs).

It added: "Life on Earth consisted of only single-celled organisms, and it would be another billion years before even the simplest multi-cellular life began to evolve."

4. The Parkes Telescope in Australia had spotted FRBs for the first time. The phenomenon was later observed by numerous radio telescopes across the world. FRBs are basically radiant emissions from distant galaxies.

ALSO READ: NASA's Cassini is heading towards its Grand Finale on September 15: Top things to know

5. The sources of FRBs are distant and usually unidentified. Discovered on November 2, 2012, FRB 121102 is believed to be the source of these 15 radio bursts. FRB 121102 is the only one known to repeat: More than 150 high-energy bursts have been observed coming from the object. It was identified last year as a dwarf galaxy located 3 million light years from Earth.

6. Researchers are trying to understand what leads to the formation of FRBs, and the dwarf galaxy has turned into the main target for all the monitoring operations carried out across the world.

"As well as confirming that the source is in a newly active state, the high resolution of the data obtained by the Listen instrument will allow measurement of the properties of these mysterious bursts at a higher precision than ever possible before," said the Breakthrough Listen statement. </s> July 2 (UPI) -- The European Southern Observatory's Very Large Telescope has captured detailed imagery of a newborn planet carving a path through the protoplanetary disk surrounding PDS 70, a young dwarf star.

According to ESO, the observations -- captured by SPHERE, VLT's planet-hunting instrument -- included the "first confirmed image of a planet caught in the act of forming in the dusty disc surrounding a young star."

The telescope's SPHERE instrument was able to observe the exoplanet at multiple wavelengths, revealing the young planet's atmosphere.

The observations suggest PDS 70b is a giant gas planet several times more massive than Jupiter. The exoplanet boasts a surface temperature of roughly 1000 degrees Celsius, more than twice as hot as Mercury, the hottest planet in our solar system.

SPHERE uses multi-wavelength observations, a coronagraph and a technique called high-contrast imaging to filter out the signal of faint exoplanets circling bright stars. The coronagraph, which appears as a dark circle in the middle of the VLT image, works to block out the bright light of the host star -- emissions that would otherwise overwhelm the telescope's ability to photograph and analyze the characteristics of the protoplanetary disk.

The new image suggests the newborn planet has created sizable gaps in the protoplanetary disk.

"Keppler's results give us a new window onto the complex and poorly-understood early stages of planetary evolution," André Müller, a researcher at the Max Planck Institute for Astronomy, said in a news release. "We needed to observe a planet in a young star's disc to really understand the processes behind planet formation."

Data revealing the chemical makeup of the exoplanet's atmosphere will help scientists model the gas giant's formation and early evolution.

Scientists detailed their discovery and analysis of PDS 70b in a pair of papers, soon to be published in the journal Astronomy and Astrophysics. </s> This amazing discovery is the first solid proof of a binary star system, NASA reveals.

NASA’s Hubble Space Telescope has detected a space crime, Outer Places reports. The telescope caught a glimpse of a “stellar thief,” a star that had been siphoning hydrogen from a nearby supernova, quite possibly leading to its neighbor’s extinction.

NASA provides the whole back story in a recent news release, explaining that the supernova, called SN 2001ig, was first sighted 17 years ago, when the light from its explosion eventually reached Earth. It’s swindling companion, however, was only recently observed, once the glare from the explosion started fading away and exposed a suspect presence near the dying star.

This cosmic murder mystery has a deep significance for the astronomers who uncovered it. This is the first time anyone has found actual proof that some massive stars, just like the one that was killed off in the supernova, can occur in binary star systems, where they coexist next to a companion star.

This first-ever documented binary star system was discovered by Hubble in “a galaxy far, far away,” lying at a distance of 40 million light-years from Earth, in the Grus constellation, also known as the Crane. The galaxy’s name is NGC 7424.

The Hubble photo that tied it all together “is the most compelling evidence that some supernovas originate in double-star systems,” NASA revealed in the news release.

The fortuitous discovery is also detailed in study published last month in the Astrophysical Journal.

“We know that the majority of massive stars are in binary pairs,” said lead study author Stuart Ryder, from the Australian Astronomical Observatory (AAO) in Sydney, Australia.

“Many of these binary pairs will interact and transfer gas from one star to the other when their orbits bring them close together,” he explained in the news release.

This was also the case with SN 2001ig and its stellar companion. SN 2001ig is a rare type of supernova, categorized as a Type IIb stripped-envelope supernova, which means that most of the hydrogen in is “stellar envelope” — the region of the star which transports materials from its core to its atmosphere — had already been depleted before the explosion.

The reason was none other than its thieving companion, which had been stealing hydrogen from SN 2001ig for millions of years, long before its unsuspecting victim went supernova.

With its neighbor constantly mooching off hydrogen, SN 2001ig eventually became unstable and started “to episodically blow off a cocoon and shells of hydrogen gas before the catastrophe,” states the NASA news release.

Similar occurrences are common in the universe, since “the sheer number of stripped-envelope supernovas is greater than predicted,” says study co-author Ori Fox of the Space Telescope Science Institute in Baltimore.

But Hubble was the first to ever capture evidence that binary star systems, long-time predicted, really exist.

“We were finally able to catch the stellar thief, confirming our suspicions that one had to be there,” said study co-author Alex Filippenko of the University of California, Berkeley, who was the first to discover Type IIb stripped-envelope supernovae in 1987. </s> Large objects in space tend to distort and magnify the light coming from objects behind them, allowing scientists to see things which would otherwise not be observable at all. This phenomenon is called gravitational lensing and using it, astrophysicists from University of Oklahoma (OU) have discovered, for the first time, planets outside the Milky Way.

Exoplanets — the name given to all planets outside our solar system — were first discovered in 1992, and thousands have been discovered since. But all those known exoplanets are inside our home galaxy. But Xinyu Dai and Eduardo Guerras from OU published a paper Friday in which they identify the presence of about 2,000 planetary mass bodies in a galaxy located 3.8 billion light-years away.

The galaxy they studied is a quasar, RXJ 1131-1231, which is thought to be a phase in the evolution of some galaxies. The supermassive black hole at its center wields an enormous amount of gravity, which causes gravitational lensing. The planets it revealed range in mass from the moon to Jupiter, and are likely unbound — they don’t orbit stars.

“We are very excited about this discovery. This is the first time anyone has discovered planets outside our galaxy. These small planets are the best candidate for the signature we observed in this study using the microlensing technique. We analyzed the high frequency of the signature by modeling the data to determine the mass,” Dai explained in a statement.

The raw data for the observations came from NASA’s Chandra X-ray Observatory, a space telescope operated by the Smithsonian Astrophysical Observatory. The microlensing models were made at the university. And the researchers stressed using a technique like gravitational lensing was the only way to make such a discovery.

“This is an example of how powerful the techniques of analysis of extragalactic microlensing can be. This galaxy is located 3.8 billion light years away, and there is not the slightest chance of observing these planets directly, not even with the best telescope one can imagine in a science fiction scenario. However, we are able to study them, unveil their presence and even have an idea of their masses. This is very cool science,” Guerras said in the statement.

The paper, titled “Probing Planets in Extragalactic Galaxies Using Quasar Microlensing,” appeared in the Astrophysical Journal Letters.

Another paper, also published Friday by an international team of researchers, used gravitational lensing to set a new magnification record of sorts. With a massive galaxy cluster in the foreground, the scientists identified a distant galaxy, located about 22 billion light-years away, because it had been magnified 30 times.

“The very high magnification of this image provides us with a rare opportunity to investigate the stellar populations of this distant object and, ultimately, to reconstruct its undistorted shape and properties,” study coauthor Johan Richard from University of Lyon, France, said in a statement.

Similar magnification has been observed before, but why this one stands out is due to the nature of the background galaxy which was discovered. It is a quiescent galaxy, which means it doesn’t produce new stars and is therefore extremely faint. Considered the last of galactic evolution, quiescent galaxies are common even in the local universe.

“As we look at more distant galaxies, we are also looking back in time, so we are seeing objects that are younger and should not yet have used up their gas supply. Understanding why this galaxy has already stopped forming stars may give us critical clues about the processes that govern how galaxies evolve,” Mikkel Stockmann, another coauthor, from the University of Copenhagen, said in the statement.

The data for this study was taken from observations made by the Hubble Space Telescope.

Titled “Thirty-fold: Extreme Gravitational Lensing of a Quiescent Galaxy at z = 1.6,” this study also appeared in the Astrophysical Journal Letters. The lead author was Harald Ebeling from the University of Hawaii.

Gravitational lensing is a very useful tool for studying distant objects in space, but it can also create problems for astronomers who study the Cosmic Microwave Background — the omnipresent radiation from soon after the Big Bang, one of the few things which allow us to study the universe in its infancy. The strong gravitational effects of various large objects in space complicates the observation of the CMB, and researchers have previously proposed a “delensing” method to overcome this encumbrance. </s> Seventeen years after the initial stellar explosion, astronomers were able to locate the surviving companion to a supernova. Photo by Hubble/NASA/ESA

April 27 (UPI) -- The Hubble Space Telescope has captured the best evidence yet that double-star systems host supernovas.

Seventeen years after astronomers first spotted a supernova 40 million light-years away in the galaxy NGC 7424, a Hubble photograph revealed a second star, the supernova's surviving companion.

"We know that the majority of massive stars are in binary pairs," Stuart Ryder, researcher at the Australian Astronomical Observatory in Sydney, said in a news release. "Many of these binary pairs will interact and transfer gas from one star to the other when their orbits bring them close together."

The companion in Hubble's image was more than just a spectator to the action 17 years ago. The companion is a cosmic criminal, guilty of theft. Millions of years before its companion exploded a fire death, the star was creating instability in the primary star by siphoning off hydrogen from its stellar envelope, the layer that shuttles energy from the core to the star's atmosphere.

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As a result of millions of years of theft, the primary star demise, dubbed SN 2001ig, was classified as a Type IIb stripped-envelope supernova, an explosion characterized by a lack of hydrogen.

Most scientists thought Type IIb stripped-envelope supernovas originated in single star systems, their out envelopes blown away by strong stellar winds. But over the years, astronomers have struggled to find the primary stars responsible for such explosions.

"That was especially bizarre because astronomers expected that they would be the most massive and the brightest progenitor stars," said Ori Fox of the Space Telescope Science Institute in Baltimore. "Also, the sheer number of stripped-envelope supernovas is greater than predicted."

Astronomers now think as many as half of all Type IIb stripped-envelope supernovas may originate in binary star systems.

The revelation might not have happened if SN 2001ig occurred just a little farther away. The stellar system sits right on the edge of Hubble's photographic limits. The companion is so faint, it likely would be invisible to Hubble if it was a few more light-years away. A bit of luck allowed for the breakthrough.

"We were finally able to catch the stellar thief, confirming our suspicions that one had to be there," said Alex Filippenko, astronomer at the University of California, Berkeley.

RELATED Colorful spiral galaxies collide in new Hubble video

RELATED Hubble captures glow of giant galaxy cluster </s> Following the posting on the ATel #11454 about the discovery by All Sky Automated Survey for SuperNovae survey () of a new transient source, Carina (ASAS-SN Designation: ASASSN-18fv) I performed some follow-up of this object through a 0.43-m f/6.8 astrograph + CCD from MPC Code Q62 (iTelescope Observatory, Siding Spring).On images taken on March 23.4, 2018 I can confirm the presence of an optical counterpart with R-filtered CCD magnitude +5.7 at coordinates:R.A. = 10 36 15.42, Decl.= -59 35 53.7(equinox 2000.0; UCAC-4 catalogue reference stars).Below you can see my confirmation image (single 20-sec exposure through a 0.43-m f/6.8 astrograph + CCD), click on it for a bigger version:While below you can see a wide-field color image (90 second exposures) I obtained on March 23.4, 2018 through a Takahashi SKY90 Apochromatic Refractor f5/6 + Color CCD. In the imageis visible at the centre of the field together with part of the Carina Nebula (click on it for a bigger version):This transient was discovered using data from the quadruple 14-cm "Cassius" telescope in CTIO, Chile of ASAS-SN survey on images obtained on UT 2018-03-20.32 at V<10 2018-03-16.32="" also="" asas-sn="" asassn-18fv="" at="" detected="" detection="" no="" on="" possibly="" saturated="" starting="" ut="" v="">17.0) of this object in subtracted images taken on UT 2018-03-15.34 and before by the same survey. No previous outbursts or variability are detected at the position of ASASSN-18fv since ASAS-SN started observing this location in February 2016.According to Atel #11467 pre-discovery images have been identified on images obtained by, an array of 6-cm telescopes continuously monitoring 8000 square degrees of sky at 2-minute cadence from CTIO, Chile. The transient is not detected at UT 2018-03-16.0316 with an upper-limit of 11.9 +/- 0.1 mag (g'). Beginning at UT 2018-03-16.227, they detected a new source at 10.21 +/- 0.05 mag (g'). (click on the images below for a bigger version).An animation showing a comparison between my confirmation image and the archive POSS2/UKSTU Red plate (1991-02-10). Click here for a bigger version.Spectroscopy by P. Luckas (see ATel #11460 ) seems to indicate that ASASSN-18fv is a classical nova brightening and in the optically thick (Fe curtain) phase.But according to L. Izzo et al. ( ATel #11468 ): "The lack of a strong blue continuum, that is however typical of classical nova outburst, and the low expansion velocities suggest a possible different nature for this object. The presence of many narrow absorptions also suggests a similarity with other peculiar explosions, like the luminous red variable V4332 Sgr (Martini et al. 1999), the possible luminous red novae V838 Mon and V1309 Sco (Tylenda et al. 2011, Mason et al. 2010) or the 'helium-flash' explosion observed in the Sakurai object (Duerbeck and Benetti 1996)". Doubts about the nova nature of this object were expressed also by J. Strader et al. ( ATel #11456 </s> A planet-hunting instrument has captured the first confirmed image of a newborn planet that’s still forming in our galaxy.

To the right of the black circle at the center of the image, the round bright planet can be seen within the disk of gas and dust around the young dwarf star PDS 70. Of course, the center isn’t naturally this dark. Instead, the researchers used a coronagraph to block the bright light of the star in order to look at the disk and the planet.

It’s carving out a path through the disk around the star, which is in the Centaurus constellation. The protoplanetary disk is the “planet factory” full of gas and dust around young stars. The planet was found in a gap in this disk, which means it is close to where it was born and still growing by accumulating material from the disk.

The planet, dubbed PDS 70b, was detected by an international team using the European Southern Observatory’s Very Large Telescope in Chile and its planet-hunting instrument, called SPHERE. The instrument is considered to be one of the most powerful planet hunters in existence.

The discovery by two teams of researchers is detailed in two papers published in the journal Astronomy & Astrophysics on Monday.

“These discs around young stars are the birthplaces of planets, but so far only a handful of observations have detected hints of baby planets in them,” Miriam Keppler of the Max Planck Institute for Astronomy, who led one team, said in a statement. “The problem is that until now, most of these planet candidates could just have been features in the disc.”

André Müller, also with the Max Planck institute and leader of the second team, said in a statement that “Keppler’s results give us a new window onto the complex and poorly-understood early stages of planetary evolution. We needed to observe a planet in a young star’s disc to really understand the processes behind planet formation.”

SPHERE was able to measure the planet’s brightness at different wavelengths, which enabled the researchers to determine the properties of its atmosphere.

This is incredibly challenging, because even though SPHERE used the coronagraph to block the star, it had to seek out the planet’s signal in multiple ways.

Researchers were able to determine that it’s a giant gas planet and has a blisteringly hot surface temperature of 1,832 degrees Fahrenheit. This is at least a few times the mass of Jupiter, the largest gas giant in our solar system, and well above the highest temperature recorded on any planet in our solar system.

They also deduced that it has a cloudy atmosphere.

Although the planet looks close to its star in the image, it’s 1,864,113 miles away. That’s the same distance as Uranus from our sun. It takes the planet 120 years to orbit the star, which fits with astronomers’ predictions that gas giants would need to form quite far from their stars.

Directly imaging the planet is a game-changer. Going forward, researchers will be able test models of how planets form and learn more about the history of how the earliest planetary systems formed, like our own solar system.

“After more than a decade of enormous efforts to build this high-tech machine, now SPHERE enables us to reap the harvest with the discovery of baby planets!” Thomas Henning, director at the Max Planck Institute for Astronomy and leader of the teams, said in a statement. </s> For the last few years, Chuck Hailey has had the center of the Milky Way hanging in his office at Columbia University. The picture, pinned above his desk, shows a bright orange and yellow blob—the glow of cosmic gas as it gets devoured by the supermassive black hole at the center of the galaxy. Astronomers captured this glow using X-rays, a versatile type of radiation that’s good for seeing through galactic gas as well as human bodies. Some of the X-ray emissions astronomers detect coming from the galactic center come from this black hole, known as Sagittarius A*, but not all. The rest comes from a population of other, smaller black holes clustered in the region. Astronomers have long predicted the presence of such black holes at the center of the galaxy, which they said could number in the thousands. Now, Hailey and his colleagues have found the first evidence of these black holes. Using archival data from the Chandra X-ray Observatory, a telescope orbiting Earth, Hailey and his team at Columbia picked out 12 X-ray sources within a few light-years of the galactic center that they believe are some of these smaller black holes. Their research was published Wednesday in Nature.

The dozen black holes are small as far as black holes go, about 10 times the mass of our sun. They are infinitesimal, of course, compared to the supermassive black hole they surround, which is about 4 million times the mass of the sun. Here’s what Chandra captured (the blue dots are the newly discovered black holes): Courtesy of Nature and Hailey et al. Astronomers found the smaller black holes by looking for their victims. When a black hole orbits together with a star, in a formation known as a binary system, the black hole feeds on its companion, sucking the starlight into the shadows. The slow process of devouring the companion star produces a glowing disk of hot gas that can be seen by powerful telescopes through X-rays. This is why Hailey and his team were able to spot these black holes out of all the thousands out there. Without cannibalized stars to light the way, we can't see black holes with current technology “A black hole all by its lonesome doesn’t do much of anything, and even when it eats some gas or dust, it’s very inefficient at converting its food to X-rays or any other form of radiation,” Hailey says. “But when a black hole, or even a neutron star or a white dwarf, when they have a stellar companion—that is, a living star—that star will shed gas and form a disk around the black hole.” Those disks are very good at producing the X-rays detectable by powerful technology.

Hailey and his team predict there may be as many as 10,000 of these small black holes lurking in our galaxy’s center. They make this estimate based on astronomers’ observations of similar black holes with stellar companions closer to Earth—oh yeah, there are black holes floating around the entire Milky Way—and their X-ray emissions. If these black holes were in the galactic center, they’d be too dim for us to spot from here. “We’re seeing the tip of the iceberg,” Hailey said. “We’re actually missing most of them just because the center of the galaxy is so far away.” The new detection makes Hailey wonder just how many of these black holes are floating around without a star companion, completely invisible to our telescopes. It’s actually quite rare for a black hole to successfully lasso a star with its gravity and start chomping down on it, so there must be many more out there without a companion than with one, Hailey said. If the thought of thousands of black holes swirling about the center of your galaxy scares you, don’t worry. These mysterious objects are no threat to our little planet. But let’s say—just for fun—you found yourself at the galactic center, hurtling through the region alongside particles of cosmic dust. In that situation, it would actually be more advantageous to get swallowed up by the supermassive black hole instead of one of the smaller ones. Both would kill you, of course. But the bigger black hole would make the journey less painful, says Sera Markoff, an astrophysicist at the University of Amsterdam and a member of the Event Horizon Telescope, a project that’s striving to photograph a black hole for the first time. Every black hole is surrounded by an invisible boundary called the event horizon, beyond which nothing, not even light, can escape. Anything that crosses that horizon is a goner. If you were able to hover over the event horizon, extreme tidal forces—the fierce gravitational tug of the black hole—would stretch your body to resemble a strand of spaghetti. The smaller the black hole, the more concentrated the tidal forces, and the greater the tugging, Markoff said. “So the tidal force of a supermassive black hole is gentle”—relatively speaking, of course—“and when you pass through the event horizon, you wouldn’t really feel it. You wouldn’t get shredded until much further in,” she said. While the center of a galaxy would destroy any living creature that ended up there, from a cosmic perspective, it is a place of creation. Hailey likens it to a nursery for cultivating celestial objects. “It’s sort of like fertile soil in which to grow big stars, which then collapse into these black holes and then grab another star,” he said. This process produces the fertilizer for everything else in the universe, expelling the heavy elements that help seed new stars, planets and, in some lucky places, life.
European astronomers observe the "birth" of a symbiotic X-ray binary, IGR J17329-2731, described as a transient, from the Galactic Center using INTEGRAL space telescope.