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Hubble observes star eating a planet

May 21, 2010 By vani Leave a Comment

Washington, May 21 (ANI): A new instrument on NASA’s Hubble Space Telescope, called the Cosmic Origins Spectrograph (COS), has observed that the hottest known planet in the Milky Way galaxy being eaten by its parent star.

The planet may only have another 10 million years left before it is completely devoured.

The planet, called WASP-12b, is so close to its Sun-like star that it is superheated to nearly 2,800 degrees Fahrenheit and stretched into a football shape by enormous tidal forces.

The atmosphere has ballooned to nearly three times Jupiter’s radius and is spilling material onto the star.

The planet is 40 percent more massive than Jupiter.

This effect of matter exchange between two stellar objects is commonly seen in close binary star systems, and this is the first time it has been seen so clearly for a planet.

“We see a huge cloud of material around the planet which is escaping and will be captured by the star. We have identified chemical elements never before seen on planets outside our own solar system,” said team leader Carole Haswell of The Open University in Great Britain.

A study last year predicted that the planet’s surface would be distorted by the star’s gravity, and that gravitational tidal forces make the interior so hot that it greatly expands the planet’s outer atmosphere.

Now Hubble has confirmed this prediction.

WASP-12 is a yellow dwarf star located approximately 600 light-years away in the winter constellation Auriga.

The exoplanet was discovered by the United Kingdom’s Wide Area Search for Planets (WASP) in 2008.

The automated survey looks for the periodic dimming of stars from planets passing in front of them, an effect called transiting.

The hot planet is so close to the star it completes an orbit in 1.1 days.

The unprecedented ultraviolet (UV) sensitivity of COS enabled measurements of the dimming of the parent star’s light as the planet passed in front of the star.

The UV spectral observations showed that absorption lines from aluminum, tin, manganese, among other elements became more pronounced as the planet transited the star, meaning that these elements exist in the planet’s atmosphere as well as the star’s.

The fact the COS could detect these features on a planet offers strong evidence that the planet’s atmosphere is greatly extended because it is so hot.

The UV spectroscopy was also used to calculate a light curve to precisely show just how much of the star’s light is blocked out during transit.

The depth of the light curve allowed the COS team to accurately calculate the planet’s radius.

They found that the UV-absorbing exosphere is much more extended than that of a normal planet that is 1.4 times Jupiter’s mass.

It is so extended that the planet’s radius exceeds its Roche lobe, the gravitational boundary beyond which material would be lost forever from the planet’s atmosphere.

The results were published in the latest issue of The Astrophysical Journal Letters. (ANI)

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Galaxy hosting most distant supermassive black hole ever found

September 3, 2009 By admin Leave a Comment

Washington, September 3 (ANI): A team of astronomers from the University of Hawaii has discovered a giant galaxy surrounding the most distant supermassive black hole ever found.

The galaxy, which is 12.8 billion light-years from Earth, is as large as the Milky Way galaxy and harbors a supermassive black hole that contains at least a billion times as much matter as does our Sun.

According to University of Hawaii astronomer Dr. Tomotsugu Goto, “It is surprising that such a giant galaxy existed when the Universe was only one-sixteenth of its present age, and that it hosted a black hole one billion times more massive than the Sun. The galaxy and black hole must have formed very rapidly in the early universe.”

Knowledge of the host galaxies of supermassive black holes is important in order to understand the long-standing mystery of how galaxies and black holes have evolved together.

Unlike smaller black holes, which form when a large star dies, the origin of supermassive black holes remains an unsolved problem.

A currently favored model requires several intermediate black holes to merge.

The host galaxy discovered in this work provides a reservoir of such intermediate black holes.

After forming, supermassive black holes often continue to grow because their gravity draws in matter from surrounding objects.

The energy released in this process accounts for the bright light that these black holes produce.

To see the supermassive black hole, the team of scientists used new red-sensitive CCDs installed in the Suprime-Cam camera on the Subaru telescope on Mauna Kea.

According to Prof. Satoshi Miyazaki of the National Astronomy Observatory of Japan (NAOJ), lead investigator for the creation of the new CCDs and a collaborator on this project, “The improved sensitivity of the new CCDs has brought an exciting discovery as its very first result.”

A careful analysis of the colors revealed that 40 percent of light around 9100 angstroms is from the host galaxy itself and 60 percent is from the surrounding ionized nebulae illuminated by the black hole.

“We have witnessed a supermassive black hole and its host galaxy forming together. This discovery has opened a new window for investigating galaxy-black hole co-evolution at the dawn of the universe,” said Dr. Yousuke Utsumi, a member of the project team. (ANI)

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Milky Way’s “dark matter” mystery solved by astrophysicists

July 10, 2009 By admin Leave a Comment

Washington, July 9 (ANI): A team of astrophysicists has solved a mystery that led some scientists to speculate that the distribution of certain gamma rays in our Milky Way galaxy was evidence of a form of undetectable “dark matter” believed to make up much of the mass of the universe.

In two separate scientific papers, the astrophysicists show that this distribution of gamma rays can be explained by the way “antimatter positrons” from the radioactive decay of elements, created by massive star explosions in the galaxy, propagate through the galaxy.

Thus, the scientists said, the observed distribution of gamma rays is not evidence for dark matter.

“There is no great mystery,” said Richard Lingenfelter, a research scientist at UC San Diego’s Center for Astrophysics and Space Sciences who conducted the studies with Richard Rothschild, a research scientist also at UCSD, and James Higdon, a physics professor at the Claremont Colleges.

“The observed distribution of gamma rays is in fact quite consistent with the standard picture,” he added.

Over the past five years, gamma ray measurements from the European satellite INTEGRAL have perplexed astronomers, leading some to argue that a “great mystery” existed because the distribution of these gamma rays across different parts of the Milky Way galaxy was not as expected.

To explain the source of this mystery, some astronomers had hypothesized the existence of various forms of dark matter, which astronomers suspect exists, but have not yet found.

What is known for certain is that our galaxy and others are filled with tiny subatomic particles known as positrons, the antimatter counterpart of typical, everyday electrons.

The scientists calculated that most of the gamma rays should be concentrated in the inner regions of the galaxy, just as was observed by the satellite data.

“The observed distribution of gamma rays is consistent with the standard picture where the source of positrons is the radioactive decay of isotopes of nickel, titanium and aluminum produced in supernova explosions of stars more massive than the Sun,” said Rothschild.

The scientists point out that a basic assumption of one of the more exotic explanations for the purported mystery – dark matter decays or annihilations – is flawed, because it assumes that the positrons annihilate very close to the exploding stars from which they originated.

“We clearly demonstrated this was not the case, and that the distribution of the gamma rays observed by the gamma ray satellite was not a detection or indication of a ‘dark matter signal’,” said Lingenfelter. (ANI)

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Astronomers spot a pair of solar systems in the making

July 2, 2009 By admin Leave a Comment

Washington, July 2 (ANI): Two University of Hawaii astronomers have found a binary star-disk system in which each star is surrounded by the kind of dust disk that is frequently the precursor of a planetary system, which makes them solar systems in the making.

The astronomers in question are doctoral student Rita Mann and Dr. Jonathan Williams, who used the Submillimeter Array on Mauna Kea, Hawaii, to make the observations.

A binary star system consists of two stars bound together by gravity that orbit a common center of gravity.

Most stars form as binaries, and if both stars are hospitable to planet formation, it increases the likelihood that scientists will discover Earth-like planets.

This binary system, 253-1536, stands out as the first known example of two optically visible stars, each surrounded by a disk with enough mass to form a planetary system like our own.

It lies 1,300 light-years from Earth, in the famous Orion Nebula, the kind of rich cluster of stars that is a common birth environment for most stars in our Milky Way galaxy, including our Sun.

One of the disks was discovered in an image taken with the Hubble Space Telescope, but the other disk was hidden in the glare of the star.

Hubble saw only the disk shadow, so the amount of material and its capability for planet formation was unknown until the UH team made the SMA observations.

The two stars are 400 times farther from each other than Earth is from the Sun.

They would take 4,500 years, or about the length of human recorded history, to complete one orbit around their common center.

Both stars are only about a third the mass of our Sun and are much cooler and redder in color.

The larger disk in 253-1536 is also the most massive found in the Orion Nebula so far.

The discovery of this massive disk and the binary disk system improve our understanding of how common planet formation is in our Galaxy and place our Solar System in context. (ANI)

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Astronomers unveil largest map of cold cosmic dust

July 2, 2009 By admin Leave a Comment

Berlin, July 2 (ANI): Astronomers have unveiled the largest map of cold cosmic dust, which are peppered in the inner regions of the Milky Way galaxy, and are the potential birthplaces of new stars.

Made using observations from the APEX telescope in Chile, this will prove an invaluable map for observations made with the forthcoming ALMA telescope, as well as the recently launched ESA Herschel space telescope.

This new guide for astronomers, known as the APEX Telescope Large Area Survey of the Galaxy (ATLASGAL) shows the Milky Way in submillimeter-wavelength light.

Images of the cosmos at these wavelengths are vital for studying the birthplaces of new stars and the structure of the crowded galactic core.

“ATLASGAL gives us a new look at the Milky Way. Not only will it help us investigate how massive stars form, but it will also give us an overview of the larger-scale structure of our galaxy,” said Frederic Schuller from the Max Planck Institute for Radio Astronomy, leader of the ATLASGAL team.

The area of the new submillimeter map is approximately 95 square degrees, covering a very long and narrow strip along the galactic plane two degrees wide (four times the width of the full Moon) and over 40 degrees long.

The Universe is relatively unexplored at submillimeter wavelengths, as extremely dry atmospheric conditions and advanced detector technology are required for such observations.

The interstellar medium – the material between the stars – is composed of gas and grains of cosmic dust, rather like fine sand or soot.

However, the gas is mostly hydrogen and relatively difficult to detect, so astronomers often search for these dense regions by looking for the faint heat glow of the cosmic dust grains.

Submillimeter light allows astronomers to see these dust clouds shining, even though they obscure our view of the Universe at visible light wavelengths.

Accordingly, the ATLASGAL map includes the denser central regions of our galaxy, in the direction of the constellation of Sagittarius – home to a supermassive black hole that are otherwise hidden behind a dark shroud of dust clouds.

The newly released map reveals thousands of dense dust clumps, many never seen before, which mark the future birthplaces of massive stars.

The clumps are typically a couple of light-years in size, and have masses of between ten and a few thousand times the mass of our Sun. (ANI)

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Milky Way survived ancient heat wave because of dark matter

July 1, 2009 By admin Leave a Comment

Washington, July 1 (ANI): A new theory by scientists says that our Milky Way galaxy survived intense heat generated by the “ignition” of the Universe about half-a-billion years after the Big Bang, because it was already immersed in a large clump of dark matter that trapped gases inside it.

Tiny galaxies, inside small clumps of dark matter, were blasted away by the heat that reached approximate temperatures of between 20,000 and 100,000 degrees centigrade, according to the scientists, including experts at Japan’s University of Tsukuba.

The researchers said that the early Milky Way, which had begun forming stars, held on to the raw gaseous material from which further stars would be made.

This material would otherwise have been evaporated by the high temperatures generated by the “ignition”.

Using computer simulations carried out by the international Virgo Consortium (which is led by Durham), the scientists examined why galaxies like the Milky Way have so few companion galaxies or satellites.

Astronomers have found a few dozen small satellites around the Milky Way, but the simulations revealed that hundreds of thousands of small clumps of dark matter should be orbiting our galaxy.

Dark matter is thought to make up 85 per cent of the Universe’s mass and is believed to be one of the building blocks of galaxy formation.

The scientists said the heat from the early stars and black holes rendered this dark matter barren and unable to support the development of satellite star systems.

According to Joint lead investigator Professor Carlos Frenk, Director of the Institute for Computational Cosmology, at Durham University, “The validity of the standard model of our Universe hinges on finding a satisfactory explanation for why galaxies like the Milky Way have so few companions.”

“The simulations show that hundreds of thousands of small dark matter clumps should be orbiting the Milky Way, but they didn’t form galaxies,” he explained.

“We can demonstrate that it was almost impossible for these potential galaxies to survive the extreme heat generated by the first stars and black holes,” he added.

“The heat evaporated gas from the small dark matter clumps, rendering them barren. Only a few dozen front-runners which had a head start on making stars before the Universe ignited managed to survive,” he further added.

By providing a natural explanation for the origin of galaxies, the simulations support the view that cold dark matter is the best candidate for the mysterious material believed to make up the majority of our Universe. (ANI)

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Herschel and Planck on their way to unlock secrets of the Universe

May 15, 2009 By admin Leave a Comment

Washington, May 15 (ANI): The Herschel and Planck spacecraft have successfully blasted into space on May 14 from the Guiana Space Centre in French Guiana, in a mission to unlock the secrets of the Universe.

The European Space Agency (ESA) missions, with significant participation from NASA, hitched a ride together on an Ariane 5 rocket, but now have different journeys before them.

Herschel will explore, with unprecedented clarity, the earliest stages of star and galaxy birth in the universe; it will help answer the question of how our Sun and Milky Way galaxy came to be.

Planck will look back to almost the beginning of time itself, gathering new details to help explain how our universe came to be.

“These two missions have spent a lot of time together,” said Ulf Israelsson, NASA project manager for both Herschel and Planck at NASA’s Jet Propulsion Laboratory, Pasadena, California.

“But now they are going their separate ways, each ready to do what it does best,” he added.

The spacecraft are traveling on separate trajectories to a point in the Earth-Sun system called the second Lagrangian point, four times farther away than the moon’s orbit, or an average distance of 1.5 million kilometers from Earth.

They will spend the rest of their missions independently orbiting this point – located on the other side of Earth from the Sun – as they make their way around the Sun every year.

Herschel will start preparing for science operations while en route toward its operational orbit, which will be reached in about two months.

Four months later, the science mission will begin and is expected to last more than three-and-a-half years.

Planck will reach a similar orbit in roughly two months, with science observations beginning one month later.

The mission’s science operations are scheduled to last a minimum of 15 months, with the possibility of an extension.

Herschel will make the most detailed measurements yet of the cold and dark wombs where the embryos of stars and galaxies have just begun to grow.

It will also be able to detect key elements and molecules involved in a star’s life, tracing their evolution from atoms to potentially life-forming materials.

Planck will see light that has traveled billions of years from the newborn universe to reach us.

This light, called the cosmic microwave background, contains information about the Big Bang that created space and time itself.

According to Charles Lawrence, the NASA Planck project scientist at JPL, “Our previous images of the baby universe were like fuzzy snapshots. Now, we’ll have the cleanest, deepest and sharpest images ever made of the early universe.” (ANI)

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NASA’s Kepler mission begins hunt for planets like Earth

April 17, 2009 By admin Leave a Comment

Washington, April 17 (ANI): NASA’s Kepler mission has taken its first images of the star-rich sky where it will soon begin hunting for planets like Earth.

The new images show the mission’s target patch of sky, a vast starry field in the Cygnus-Lyra region of our Milky Way galaxy.

One image shows millions of stars in Kepler’s full field of view, while two others zoom in on portions of the larger region.

“Kepler’s first glimpse of the sky is awe-inspiring,” said Lia LaPiana, Kepler’s program executive at NASA Headquarters in Washington. “To be able to see millions of stars in a single snapshot is simply breathtaking,” she added.

One new image from Kepler shows its entire field of view – a 100-square-degree portion of the sky, equivalent to two side-by-side dips of the Big Dipper.

The regions contain an estimated 14 millions stars, more than 100,000 of which were selected as ideal candidates for planet hunting.

Two other views focus on just one-thousandth of the full field of view.

In one image, a cluster of stars located about 13,000 light-years from Earth, called NGC 6791, can be seen in the lower left corner.

The other image zooms in on a region containing a star, called Tres-2, with a known Jupiter-like planet orbiting every 2.5 days.

“It’s thrilling to see this treasure trove of stars,” said William Borucki, science principal investigator for Kepler at NASA’s Ames Research Center at Moffett Field, California.

“We expect to find hundreds of planets circling those stars, and for the first time, we can look for Earth-size planets in the habitable zones around other stars like the sun,” he added.

Kepler will spend the next three-and-a-half years searching more than 100,000 pre-selected stars for signs of planets.

It is expected to find a variety of worlds, from large, gaseous ones, to rocky ones as small as Earth.

The mission is the first with the ability to find planets like ours – small, rocky planets orbiting sun-like stars in the habitable zone, where temperatures are right for possible lakes and oceans of water.

“Everything about Kepler has been optimized to find Earth-size planets,” said James Fanson, Kepler’s project manager at NASA’s Jet Propulsion Laboratory in Pasadena, California.

“Our images are road maps that will allow us, in a few years, to point to a star and say a world like ours is there,” he added. (ANI)

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Discovery of recently formed galaxies poses challenge to galaxy formation theories

April 11, 2009 By admin Leave a Comment

Washington, April 11 (ANI): A team of astronomers has found a sample of massive galaxies with properties that suggest they may have formed relatively recently, a discovery that poses challenge to galaxy formation theories.

This runs counter to the widely-held belief that massive, luminous galaxies (like our own Milky Way Galaxy) began their formation and evolution shortly after the Big Bang, some 13 billion years ago.

Further research into the nature of these objects could open new windows into the study of the origin and early evolution of galaxies.

As part of the research, the team of astronomers, led by IU (Indiana University) astronomer John Salzer, uncovers the unique properties of 15 galaxies.

According to John Salzer, principal investigator for the study, the 15 galaxies in the sample exhibit luminosities (a measure of their total light output) that indicate that they are massive systems like the Milky Way and other so-called “giant” galaxies.

However, these particular galaxies are unusual because they have chemical abundances that suggest very little stellar evolution has taken place within them.

Their relatively low abundances of “heavy” elements (elements heavier than helium, called “metals” by astronomers) imply the galaxies are cosmologically young and may have formed recently.

The chemical abundances of the galaxies, combined with some simple assumptions about how stellar evolution and chemical enrichment progress in galaxies in general, suggest that they may only be 3 or 4 billion years old, and therefore formed 9 to 10 billion years after the Big Bang.

Most theories of galaxy formation predict that massive, luminous systems like these should have formed much earlier.

If this overall interpretation proves correct, the galaxies may allow astronomers to investigate phases of the galaxy formation and evolution process that have been difficult to study because they normally occur at such early times in the Universe, and therefore at very large distances from us.

“These objects may represent a unique window on the process of galaxy formation, allowing us to study relatively nearby systems that are undergoing a phase in their evolution that is analogous to the types of events that, for most galaxies, typically occurred much earlier in the history of the Universe,” Salzer said.

The discoveries are the result of a multi-year survey of more than 2,400 star-forming galaxies called the Kitt Peak National Observatory International Spectroscopic Survey (KISS).

The survey was designed to collect basic observational data for a large number of extragalactic emission-line sources. (ANI)

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Star that was 1 mln times brighter than Sun before exploding as supernova

March 23, 2009 By admin Leave a Comment

Washington, March 23 (ANI): NASA’s Hubble Space Telescope has identified a star that was one million times brighter than the Sun before it exploded as a supernova in 2005.

According to current theories of stellar evolution, the star should not have self-destructed so early in its life.

“This might mean that we are fundamentally wrong about the evolution of massive stars, and that theories need revising,” said Avishay Gal-Yam of the Weizmann Institute of Science, Rehovot, Israel.

The doomed star, which is estimated to have had about 100 times our Sun’s mass, was not mature enough, according to theory, to have evolved a massive iron core of nuclear fusion ash.

This is the prerequisite for a core implosion that triggers a supernova blast.

The explosion, called supernova SN 2005gl, was seen in the barred-spiral galaxy NGC 266 on October 5, 2005.

Pre-explosion pictures from the Hubble archive, taken in 1997, reveal the progenitor as a very luminous point source with an absolute visual magnitude of -10.3.

The progenitor was so bright that it probably belonged to a class of stars called Luminous Blue Variables (LBVs), “because no other type of star is as intrinsically brilliant,” said Gal-Yam.

As an LBV-class star evolves, it sheds much of its mass through a violent stellar wind.

Only at that point does it develop a large iron core and ultimately explodes as a core-collapse supernova.

Extremely massive and luminous stars topping 100 solar masses, such as Eta Carinae in our own Milky Way Galaxy, are expected to lose their entire hydrogen envelopes prior to their ultimate explosions as supernovae.

“These observations demonstrate that many details in the evolution and fate of LBVs remain a mystery. We should continue to keep an eye on Eta Carinae – it may surprise us yet again,” said supernova expert Mario Livio of the Space Telescope Science Institute, Baltimore, Maryland.

According to co-author Douglas Leonard from San Diego State University, California, “The progenitor identification shows that, at least in some cases, massive stars explode before losing most of their hydrogen envelope, suggesting that the evolution of the core and the evolution of the envelope are less coupled than previously thought, a finding which may require a revision of stellar evolution theory.”

One possibility is that the progenitor to SN 2005gl was really a pair of stars, a binary system that merged.

This would have stoked nuclear reactions to brighten the star enormously, making it look more luminous and less evolved than it really is. (ANI)

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Hubble provides new evidence for dark matter around small galaxies

March 13, 2009 By admin Leave a Comment

Washington, March 13 (ANI): The NASA/ESA Hubble Space Telescope has uncovered a strong new line of evidence that halos of dark matter are embedded around small galaxies.

Looking into the turbulent center of the nearby Perseus galaxy cluster, Hubble discovered a large population of small galaxies that have remained intact while larger galaxies around them are being ripped apart by the gravitational tug of other galaxies.

The Hubble images provide further evidence that the undisturbed galaxies are enshrouded by a “cushion” of dark matter that protects them from their rough-and-tumble neighborhood.

Dark matter is an invisible form of matter that accounts for most of the Universe’s mass.

Astronomers have deduced the existence of dark matter by observing its gravitational influence on normal matter, such as stars, gas and dust.

“We were surprised to find so many dwarf galaxies in the core of this cluster that were so smooth and round and had no evidence at all of any kind of disturbance,” said astronomer Christopher Conselice of the University of Nottingham, UK, and leader of the team that made the Hubble observations.

“These dwarfs are very old galaxies that have been in the cluster for a long time. So if something was going to disrupt them, it would have happened by now. They must be very, very dark- matter-dominated galaxies,” he added.

The dwarf galaxies may have an even higher amount of dark matter than spiral galaxies.

“With these results, we cannot say whether the dark matter content of the dwarfs is higher than in the Milky Way Galaxy,” Conselice said.

“Although, the fact that spiral galaxies are destroyed in clusters, while the dwarfs are not, suggests that this is indeed the case,” he added.

First proposed about 80 years ago by Swiss astronomer Fritz Zwicky, dark matter is thought to be the glue that holds galaxies together.

Astronomers suggest that dark matter provides a vital scaffolding for the Universe, forming a framework for the formation of galaxies through gravitational attraction.

Observations by Hubble’s Advanced Camera for Surveys spotted 29 dwarf elliptical galaxies in the Perseus Cluster, located 250 million light- years away and one of the closest galaxy clusters to Earth.

Because dark matter cannot be seen, astronomers detected its presence through indirect evidence.

Conselice and his team derived a new technique for uncovering dark matter in these dwarf galaxies by determining the minimum additional mass contribution from dark matter that the dwarfs must have to protect them from being disrupted by the strong, tidal pull of gravity from larger galaxies. (ANI)

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Carbon and oxygen rich stardust sheds new light on origin of elements of life

March 13, 2009 By admin Leave a Comment

Washington, March 13 (ANI): An international research team has found evidence that some stars in the center of the Milky Way galaxy have both carbon and oxygen in the dust that surrounds them, which sheds new light on the origin of the elements of life.

“Scientists have long expected to find carbon-rich stars in our galaxy because we know that significant quantities of carbon must be created in many such stars, but carbon had not previously shown up in the clouds of gas around these stars,” said Matthew Bobrowsky, an astrophysicist in the University of Maryland’s department of physics.

As a star burns hotter and hotter, the hydrogen gas that originally made up almost all of its mass is converted, through nuclear fusion, first to helium, and then to progressively heavier elements.

The hottest region in the core fuses together the heaviest elements. And these can reach the surface of the star only when its life is almost over.

“The Big Bang produced only hydrogen and helium. Heavier elements like carbon and oxygen only come from getting ‘cooked up’ in stars,” Bobrowsky said. “Nuclear reactions in stars created the heavier elements found in life as we know it,” he added.

The team of scientists used the Spitzer Space Telescope to view each star and its surrounding clouds of dust and particles, called a planetary nebulae.

The researchers measured the light emitted by the stars and the surrounding dust and were able to identify carbon compounds based on the wavelengths of light emitted by the stars.

Looking in an area at the center of the Milky Way called the “Galactic Bulge,” the team observed 26 stars and their planetary nebulae and found 21 with carbon “signatures.”

But, the scientists did not just find carbon around these stars; they also found oxygen in these 21 dust clouds, revealing a surprising mixture of ingredients for space dust.

The finding of carbon and oxygen in the dust clouds surrounding stars suggests a recent change of chemistry in this population of stars.

“Stars in the center of the Milky Way are old and ‘metal-rich’ with a high abundance of heavy elements,” Bobrowsky said. “They are different in chemical composition than those found in the disc, farther out from the center,” he added.

Studying the chemistry of these stars helps scientists learn how the matter that makes up our earth and other planets in our galaxy left its stellar birthplaces long ago.

“If we want to understand how our galaxy, and the stars, planets and life in it, came to be the way they are, we need to understand the creation of the chemical elements of which they are composed,” Bobrowsky said. (ANI)

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