Posted on by Tammy Plotner

Free Book Downloads! National Academies Press Offers More Than 4,000 Titles

Are you hungry for knowledge? Well, if you’ve got a filet mignon appetite and a hamburger budget, then get in line as the National Academies Press is offering free PDF downloads of more than 4,000 titles from its exhaustive library.

The mission of the National Academies Press (NAP) – publisher for the National Academy of Sciences, National Academy of Engineering, Institute of Medicine, and National Research Council – is to distribute the institutions’ content as widely as possible while maintaining its financial security. The project began in 1994 when the NAP began delivering content to developing countries, and even then 65% of the files were free.

“Our business model has evolved so that it is now financially viable to put this content out to the entire world for free,” said Barbara Kline Pope, executive director for the National Academies Press. “This is a wonderful opportunity to make a positive impact by more effectively sharing our knowledge and analyses.”

Just a quick browse through the titles shows such a wealth of information that one could spend hours choosing alone! You’ll find Agriculture, Earth Sciences, Forensics, Biology, Computers, Education, Health, Industry, Math, and yes… Space and Aeronautics, just to name a few. Based on the performance of NAP’s current free PDFs, projections suggest this change will enhance distribution of PDF reports from about 700,000 downloads per year to more than 3 million by 2013.

Where do you get ’em? Just head toward the NAP Website and have fun!

Original Story Source: National Acadamies News and illustration by School Clip Art.

Posted on by Tammy Plotner

LOFAR So Far… Digging Deep Into Our Universe

A very small part of the raw LOFAR image of the field centered on the bright quasar 3C196. It shows tens of discrete sources, the faintest having a flux density of only a few mJy at 150 MHz.The image has an angular resolution of 8 arcseconds. The image still needs to be deconvolved. The data was processed by Dr. Panos Labropoulos on the EoR-cluster at the University of Groningen.

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The International LOFAR telescope is a Pan-European collaborative project led by ASTRON Netherlands Institute for Radio Astronomy. The radio telescope integrates thousands of simple dipole receivers with effective digital signal processing and high-performance computing. LOFAR can rapidly take in wide areas of the sky, aiming in multiple directions simultaneously. It also utilizes unexplored low frequencies, around around 150 MHz, which allows astronomers new insights. What has LOFAR done so far? Try capturing faint radio sources never revealed before.

An international team led by astronomers at ASTRON and the Kapteyn Institute of the University of Groningen have used the LOFAR telescope, designed and constructed by ASTRON, to make the deepest wide-field images of the sky to date. At the conference, the trouble of dealing with foreground noise was the topic – foreground noise that makes it nearly impossible to get a good radio view of the distant Universe. What researchers are looking for is the Epoch of Reionization (EoR) – a time which is postulated to have occurred in the period between about 400 and 800 million years after the Big Bang. Says the team, “During the EoR the neutral hydrogen was slowly disappearing, probably as a result of the strong ‘ionizing’ power of the first stars and quasars. Detecting the EoR is one of the hottest projects in astronomy today.”

Detecting a signal from a 13.8 billion year old event would be akin to the Holy Grail of radio astronomy, but the team of astronomers based at ASTRON and the Kapteyn Institute of the University of Groningen, headed by Prof. Ger de Bruyn, Dr. Michiel Brentjens, Prof. Leon Koopmans and Prof. Saleem Zaroubi, are willing to sift through the noise to diclose new findings. The LOFAR data images were obtained in a 6-hour synthesis on the night of 29/30 January 2011 and the evening of 1 April 2011 using 18 core stations and 7 remote stations. Signals were recorded with the High Band Antennas blanketing the frequency range from 115 – 163 MHz and then further refined.

One of the fields covered by the radio imaging is centered at the celestial North Pole since it is available year round from LOFAR’s central position. The second field is dedicated to bright, compact quasar 3C196 in the constellation of Lynx. The high resolution images already match – or even surpass – the best published images taken with the Giant Meter Wavelength Radio telescope (GMRT) in India. The images reveal a significant number of both very bright and very faint sources, spanning a so-called dynamic range of more than 200,000:1 in brightness between sources.

“This is an important record for the time being for LOFAR. The image quality, however, is still not perfect and significant improvements can be expected in the months ahead using improved knowledge of the effects of the LOFAR station beams.” says the team. “Continued efforts are also needed to improve the software to deal with imaging artifacts and the ionosphere. These two fields and several others will be observed for about 100 nights to conclusively detect signals from the EoR.”

Sounds like LOFAR is doing great so far!

Original Story Source: ASTRON.

Posted on by Tammy Plotner

Revealing A Hybrid Star Cluster

NGC 6791 - The full Hubble Advanced Camera for Surveys field (top right) is full of stars estimated to be 8 billion years old. Bottom right: The blue circles identify hotter dwarfs that are 4 billion years old. The red circles identify cooler dwarfs that are 6 billion years old. - Credit: NASA, ESA, and L. Bedin (STScI)

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Almost a century ago, astronomers Shapley and Melotte began classifying star clusters. This rough, initial go-around took in the apparent number of stars and the compactness of the field – along with color. By 1927, these “classes” were again divided to include both open and globular clusters. But there are some that simply defy definition.

According to Johns Hopkins astronomer Imants Platais, there is one case which has puzzled astronomers for decades: a well-known, seemingly open star cluster in the constellation of Lyra, named NGC 6791.

“This cluster is about twice the age of the sun and is unusually metal rich (at least twice the Sun’s metallicity),” said Platais, of the Henry A. Rowland Department of Physics and Astronomy’s Center for Astrophysical Sciences. “A couple of decades ago, it was also found that NGC 6791 contains a handful of very hot but somewhat dim stars, called hot subdwarfs. The presence of such stars in an open cluster is rare, though not unique.”

Why are these hot subdwarfs an anomaly? The facts about star clusters as we know them are that globular clusters are notoriously metal poor, while open clusters are metal rich. “The massive stars that create much of the metals live for only a short time, and when they die, they spit out or eject the metals they have created.” says the team. “The expelled metals become part of the raw material out of which the next stars are formed. Thus, there is a relationship between the age of a star and how much metal it contains: old stars have a lower metallicity than do younger ones. Less massive stars live longer than higher mass stars, so low mass stars from early generations still survive today and are studied extensively.”

A team led by Platais and Kyle Cudworth from The University of Chicago’s Yerkes Observatory set out to solve the mystery of NGC 6791 by taking a census of its stars. Their findings revealed several luminous stars in the horizontal branch of the HR diagram… Stars that would normally be found in globular clusters. The hot subdwarfs were confirmed to be genuine cluster members, but they now “appear to be simply the bluest horizontal branch stars”. What’s wrong with this picture? NGC 6791 contains simultaneously both red and very blue horizontal branch stars – making it both old and metal rich. Quite simply put, studying star clusters is key to understanding stellar evolution – unless the cluster starts breaking the rules.

“Star clusters are the building blocks of galaxies and we believe that all stars, including our own sun, are born in clusters. NGC 6791 is a real oddball among about 2,000 known open and globular star clusters in the Milky Way and as such provides a new challenge and a new opportunity, to our understanding of how stars form and evolve,” said Platais, who presented this work last week at the 218th meeting of the American Astronomical Society in Boston.

So… what about star clusters in other galaxies? Three hybrids have been discovered (2005) in the Andromeda Galaxy – M31WFS C1, M31WFS C2, and M31WFS C3. They have the same basic population and metallicity of a globular cluster, but they’re expanded hundreds of light years across and are equally less dense. Are they extended? Or perhaps a dwarf spheroidal galaxy? They don’t exist (as far as we know) in the Milky Way, but there’s always a possibility these hybrid clusters may call other galaxies home.

Until then, we’ll just keep learning.

Original Story Source: John Hopkins University.

Posted on by Tammy Plotner

Old Star Clusters Shed New Light on Starbirth

NGC 3603 - Credit: NASA, ESA, R. O'Connell (University of Virginia), F. Paresce (National Institute for Astrophysics, Bologna, Italy), E. Young (Universities Space Research Association/Ames Research Center), the WFC3 Science Oversight Committee, and the Hubble Heritage Team (STScI/AURA)

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Hovering about the galactic plane and locked in the embrace of a spiral galaxy’s arms, open star clusters usually contain up to a few hundred members and generally span around thirty light years across. Most are young, up to a few tens of millions of years old – with a few rare exceptions as old as a few billion years. We understand that over time the members of a galactic cluster slowly drift apart to form loose associations. But what we don’t understand is exactly how their stars formed.

“The net effect of this is that their stars eventually become redistributed throughout the Galaxy,” said Nathan Leigh, a PhD student at McMaster University and lead author for a study being presented this week at the CASCA 2011 meeting in Ontario, Canada. “This is how we think most of the stars in the Milky Way came to be found in their currently observed locations.”

One of the reasons we’re not able to probe deeply into the construction and evolution of galactic clusters is because they are typically hidden by a dense veil of gas and dust. Beautiful to look at… But nearly impossible to cut through in visible light. This means we can’t directly observe the process of starbirth. To help understand this process, astronomers have combined their observations of star clusters so old they date back to the beginning of the Universe itself . And, thanks to modern computing, they are also able to generate state-of-the-art simulations for stellar evolution.

“Unfortunately, most star clusters take so long to dissolve that we cannot actually see it happening. But we now understand how this process occurs, and we can look for its signatures by examining the current appearances of clusters,” said Nathan Leigh. “We have gone about this by matching up the clusters we make with our simulations to the ones we actually observe. This tells us about the conditions at the time of their formation.”

These simulations have given Leigh and collaborators the stimulus they needed to re-trace the histories of real star clusters, giving us new clues about formation. To complete their studies, they relied upon highly sophisticated observations recently taken with the Hubble Space Telescope.

“Remarkably, we are finding that all star clusters more or less share a common history, extending all the way back to their births,” said Leigh. “This came as a big surprise to us since it suggests that the problem could be much simpler than we originally thought. Our understanding of not only how stars form, but also the history of our Galaxy, just took a much bigger step forward than we were expecting.”

Source: Canadian Astronomical Society.

Posted on by Tammy Plotner

MOST… Cutting To The Heart Of A Wolf-Rayet Star

M1-67 is the youngest wind-nebula around a Wolf-Rayet star, called WR124, in our Galaxy. Credit: ESO

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In 1867, astronomers using the 40 cm Foucault telescope at the Paris Observatory, discovered three stars in the constellation Cygnus (now designated HD191765, HD192103 and HD192641), that displayed broad emission bands on an otherwise continuous spectrum. The astronomers’ names were Charles Wolf and Georges Rayet, and thus this category of stars became named Wolf–Rayet (WR) stars. Now using the Canadian MOST microsatellite, a team of researchers from the Universite de Montreal and the Centre de Recherche en Astrophysique du Quebec have made a stunning observation. They probed into the depth of the atmospheric eclipses in the Wolf-Rayet star, CV Serpentis, and observed a never before seen change of mass-loss rate.

Thanks to the service of MOST – Canada’s first space telescope and its high precision photometry – the team has observed significant changes in the depth of the atmospheric eclipses in the 30-day binary WR+O system. The equipment is aboard a suitcase-sized microsatellite (65 x 65 x 30 cm) which was launched in 2003 from a former ICBM in northern Russia. It is on a low-Earth polar orbit and has long outlived its original estimated life expectancy, offering Canadian astronomers almost eight years (and still counting) of ultra-high quality space-based data. Now this data gives us a huge insight into the heart of Wolf-Rayet stars.

Intrinsically luminous, WR stars can be massive or mid-sized, but the most interesting stage is arguably the last 10% in the lifetime of the star, when hydrogen fuel is used up and the star survives by much hotter He-burning. Towards the end of this phase, the copious supply of carbon atoms head for the stellar surface and are ejected in the form of stellar winds. WR stars in this stage are known as WC stars… and their production of carbon dust is one of the greatest mysteries of the Cosmos. These amorphous dust grains range in size from a few to millions of atoms and astronomers hypothesize their formation may requires high pressure and less than high temperatures.

“One key case is undoubtedly the sporadic dust-producing WC star in CV Ser. MOST was recently used to monitor CV Ser twice (2009 and 2010), revealing remarkable changes in the depths of the atmospheric eclipse that occurs every time the hot companion’s light is absorbed as it passes through the inner dense WC wind.” says the researchers. “The remarkable, unprecedented 70% change in the WC mass-loss rate might be connected to dust formation.”

And all thanks to the MOST tiny little satellite imaginable…

Original Story Source: AstroNews and excerpt from Wikipedia.

Posted on by Tammy Plotner

Coming To A Theatre Near You… Extreme Neutron Stars!

Artist's Conception of a Neutron Star Courtesy of NASA

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They came into existence violently… Born at the death of a massive star. They are composed almost entirely of neutrons, barren of electrical charge and with a slightly larger mass than protons. They are quantum degenerates with an average density typically more than one billion tons per teaspoonful – a state which can never be created here on Earth. And they are absolutely perfect for study of how matter and exotic particles behave under extreme conditions. We welcome the extreme neutron star…

In 1934 Walter Baade and Fritz Zwicky proposed the existence of the neutron star, only a year after the discovery of the neutron by Sir James Chadwick. But it took another 30 years before the first neutron star was actually observed. Up until now, neutron stars have had their mass accurately measured to about 1.4 times that of Sol. Now a group of astronomers using the Green Bank Radio Telescope found a neutron star that has a mass of nearly twice that of the Sun. How can they make estimates so precise? Because the extreme neutron star in question is actually a pulsar – PSR J1614-2230. With heartbeat-like precision, PSR J1614-2230 sends out a radio signal each time it spins on its axis at 317 times per second.

According to the team; “What makes this discovery so remarkable is that the existence of a very massive neutron star allows astrophysicists to rule out a wide variety of theoretical models that claim that the neutron star could be composed of exotic subatomic particles such as hyperons or condensates of kaons.”

The presence of this extreme star poses new questions about its origin… and its nearby white dwarf companion. Did it become so extreme from pulling material from its binary neighbor – or did it simply become that way through natural causes? According to Professor Lorne Nelson (Bishop’s University) and his colleagues at MIT, Oxford, and UCSB, the neutron star was likely spun up to become a fast-rotating (millisecond) pulsar as a result of the neutron star having cannibalized its stellar companion many millions of years ago, leaving behind a dead core composed mostly of carbon and oxygen. According to Nelson, “Although it is common to find a high fraction of stars in binary systems, it is rare for them to be close enough so that one star can strip off mass from its companion star. But when this happens, it is spectacular.”

Through the use of theoretical models, the team hopes to gain insight as to how binary systems evolve over the entire lifetime of the Universe. With today’s extreme super-computing powers, Nelson and his team members were able to calculate the evolution of more than 40,000 plausible starting cases for the binary and determine which ones were relevant. As they describe at this week’s CASCA meeting in Ontario, Canada, they found many instances where the neutron star could evolve higher in mass at the expense of its companion, but as Nelson says, “It isn’t easy for Nature to make such high-mass neutron stars, and this probably explains why they are so rare.”

Original story source at Physorg.com.

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Posted on by Tammy Plotner

Voyager 1 Measures Magnetic Mayhem

Artist's Conception of Voyager - Credit: NASA

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When Voyager 1 passed into the heliosheath in 2004, it became the first man-made object to explore the remote edge of the Sun’s magnetic influence. Launched by NASA on September 5, 1977, the probe was designed to study the outer Solar System and eventually interstellar space. One of its missions was to look for the heliopause – the boundary at which the solar wind transitions into the interstellar medium. What it found was mayhem…

According to NASA, Voyager 1 has crossed into an area where the velocity of the hot ionized gas, or plasma, emanating directly outward from the sun has slowed to zero. Scientists suspect the solar wind has been turned sideways by the pressure from the interstellar wind in the region between stars. “The solar wind has turned the corner,” said Ed Stone, Voyager project scientist based at the California Institute of Technology in Pasadena, Calif. “Voyager 1 is getting close to interstellar space.”

Now it has entered the heliosheath, an area ranging from 1.5 to 15 billion kilometers thick (930 million to 9.3 billion miles) and starting roughly 14 billion km (8.7 billion mi) from the Sun. But there’s nothing quiet here. This is the area where outgoing flows of solar wind begin to be repelled by interstellar particles and magnetic fields pushing towards the solar system. While passing through the heliosheath, Voyager 1 experienced many sudden and drastic changes in the surrounding magnetic field driven by structures called current sheets.

Illustration Courtesy of NASA

The team of L. F. Burlaga: Geospace Physics Laboratory, NASA Goddard Space Flight Center and N. F. Ness of the Institute for Astrophysics and Computational Sciences have been studying the ongoing results sent back by Voyager and have come to a new conclusion – there are three distinct types of current sheets.

“The structures, appearing as proton boundary layers (PBLs), magnetic holes or humps, or sector boundaries, were identified by characteristic fluctuations in either magnetic field strength or direction as the spacecraft crossed nearly 500 million km (310 million mi) of heliosheath in 2009. PBLs are defined by a rapid jump in magnetic field strength, with one observed event resulting in a doubling of the field strength in just half an hour.” said the team. “Passing through a sector boundary led to a sudden change in direction of the magnetic field. Magnetic holes saw the field strength drop to near zero before returning to the original background strength. Magnetic humps consisted of a sudden spike in strength and then a return to initial levels.”

But this isn’t the first time the Voyager has returned zero readings. In December 2004 the intrepid probe broke the barrier of the termination shock and data from Voyager 1’s Low-Energy Charged Particle Instrument was used to deduce the solar wind’s velocity. When the speed of the particles matched the speed of the spacecraft, scientists knew they had a null number on their records. “When I realized that we were getting solid zeroes, I was amazed,” said Rob Decker, a Voyager Low-Energy Charged Particle Instrument co-investigator and senior staff scientist at the Johns Hopkins University Applied Physics Laboratory in Laurel, Md. “Here was Voyager, a spacecraft that has been a workhorse for 33 years, showing us something completely new again.”

And new is what we need to continue our understanding of what lay at the furthest reaches of our now explorable space. Says Burlaga, “The firsthand detections made by Voyager 1 are likely to be extremely important for researchers trying to decide between current leading theories for the source and structure of current sheets.”

Story source: Journal of Geophysical Research – Space Physics.

Posted on by Tammy Plotner

Globular Clusters Are Real Oddballs

M80 Image Credit: NASA, The Hubble Heritage Team, STScI, AURA

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Hanging onto the outskirts of our Milky Way galaxy like cockle burs on a shaggy dog’s coat, globular clusters contain over hundreds of thousands of stars. Estimated to be up to ten billion years old, these spherical stellar seed pods are gravitationally bound together and tend to be more dense towards their cores. We’ve long known all the stars contained within a globular cluster to be about the same age and the individual members most likely formed at the same time as the parent galaxy – but what we weren’t expecting was change.

“We thought we understood these clusters very well”, says Dr. Alison Sills, Associate Professor of Physics & Astronomy. She is presenting new findings at this week’s CASCA 2011 meeting in Ontario, Canada. “We taught our students that all the stars in these clusters were formed at the same time, from one giant cloud of gas. And since that time, the individual stars may have evolved and died, but no new stars were born in the cluster.”

In 1953, astronomer Allan Sandage was performing photometry of the stars in the globular cluster M3 when he made an incredible discovery – blue stragglers. No, it’s not a down-his-luck musician waiting for a coin in his instrument case… but a main sequence star more luminous and more blue than stars at the main sequence turn-off point for the cluster. They shouldn’t belong where they are, but with masses two to three times that of the rest of the main sequence cluster stars, blue stragglers seem to be exceptions to the rule. Maybe they are a product of interaction… grappling together… pulling material from one another… and eventually merging.

Image of NGC 6397 taken by the Hubble Space Telescope, with evidence of a number of blue stragglers.

“Astronomers expect that the stars get too close to each other because of the complicated dance that stars perform in these dense clusters, where thousands of stars are packed into a relatively small space, and each star is moving through this cluster under the influence of the gravity of all the other stars. Somewhat like a traffic system with no stop lights, there are a lot of close encounters and collisions,” explains Sills.

By taking a closer look at globular clusters, the Hubble Space Telescope has given us evidence for two generations of star formation. The first is our accepted rule, but the second generation isn’t like anything else found in our Galaxy. Instead of being created from an earlier generation of expended stars, the second generation in globular clusters appears to have formed from material sloughed off by the first generation of stars. An enigma? You bet.

“Studying the normal stars in clusters was instrumental in allowing astronomers to figure out how stars lived and died”, says Dr. Sills, “but now we can look even further back, to when they were born, by using the oddballs. It pays off to pay attention to the unusual individuals in any population. You never know what they’ll be able to tell you.”

At the CASCA conference, Dr. Sills is presenting her work – a link between these two unusual forms of globular clusters. Blue stragglers and the second generation of stars would appear to have identical properties, including where they are concentrated in the cluster, and that both are.. well.. a little more “blue” than we would expect. She is investigating how the close encounters and collisions could affect the formation of this strange second generation and link the two phenomena we see in these complicated systems.

Real oddballs…

Original story soucre at Physorg.com.

Posted on by Tammy Plotner

Dead Galaxy? Don’t Think So.

University of Michigan astronomers examined old galaxies and were surprised to discover that they are still making new stars. The results provide insights into how galaxies evolve with time.

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There was a time when most astronomers concluded that elliptical galaxies were a lot like their globular clusters – full of similarly evolved and aged stars. But not anymore. Thanks to the resolving power of the Hubble Space Telescope, a team of researchers from the University of Michigan were able to peer into the heart of Messier 105 and pick out several young stars and clusters. Apparently, “The reports of my death have been greatly exaggerated…”

U-M research fellow Alyson Ford and astronomy professor Joel Bregman are scheduled to present their findings May 31 at a meeting of the Canadian Astronomical Society in London, Ontario. Using the Wide Field Camera 3 on the Hubble Space Telescope, they saw individual young stars and star clusters in four galaxies that are about 40 million light-years away. One light-year is about 5.9 trillion miles.

“Scientists thought these were dead galaxies that had finished making stars a long time ago,” Ford said. “But we’ve shown that they are still alive and are forming stars at a fairly low level.”

We’re all aware of differing galaxy structures, from grand design spirals to disturbed irregulars. However, perhaps one of the most common is the elliptical. Ranging in flat form to nearly spherical, these smooth customers can contain anywhere from hundreds of millions to over one trillion stars – and most of them are believed to be the offspring of galaxy collision. Most elliptical galaxies are composed of older, low-mass stars, with a sparse interstellar medium and minimal star formation activity. Making up somewhere between 10 to 15% of known galaxy population, they are surrounded by globular clusters and usually make their home at the center of galaxy clusters. But what elliptical galaxies aren’t known for is star formation.

“Astronomers previously studied star formation by looking at all of the light from an elliptical galaxy at once, because we usually can’t see individual stars. Our trick is to make sensitive ultraviolet images with the Hubble Space Telescope, which allows us to see individual stars.” said Ford. “”We were confused by some of the colors of objects in our images until we realized that they must be star clusters, so most of the star formation happens in associations.”

The eureka moment came when the team turned the Hubble towards a galaxy most of us have observed on a personal level – M105. Located 38 million light years away in the constellation of Leo and part of the M96 Galaxy Group, this rather ordinary looking elliptical galaxy is one of the brightest to observe. Although there wasn’t any reason to believe star formation was in progress, Ford and Bregman saw a few bright, very blue stars, resembling a single star 10 to 20 times the mass of the Sun. In addition, they also observed objects that aren’t blue enough to be single stars, but instead are clusters of many stars. When accounting for these clusters, stars are forming in Messier 105 at an average rate of one Sun every 10,000 years, Ford and Bregman concluded. “This is not just a burst of star formation but a continuous process,” Ford said.

New stars from a dead galaxy? Maybe it’s a zombie. And it’s not the first time the Hubble has looked its way, either. Investigations of the central region of M105 have revealed that this galaxy contains a massive central object of about 50 million solar masses – a supermassive black hole. Of course, this new evidence creates more questions than it answers and high among the ranks is the origin of the gas that forms the stars.

“We’re at the beginning of a new line of research, which is very exciting, but at times confusing,” Bregman said. “We hope to follow up this discovery with new observations that will really give us insight into the process of star formation in these ‘dead’ galaxies.”

Dead… But maybe not so dead, after all.

Original story source Physorg.com.

Posted on by Tammy Plotner

Crystal Rain Cradles Infant Star

NASA's Spitzer Space Telescope detected tiny green crystals, called olivine, thought to be raining down on a developing star. Image credit: NASA/JPL-Caltech/University of Toledo

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Thanks to the infrared eye of the Spitzer Space Telescope, researchers have captured evidence of “crystal rain” collapsing around a forming star. These tiny bits of green mineral – olivine – are also found in meteorites, but it’s the first time it has been observed in the dusty embryo of the stellar creation process. While it’s still unclear how these crystals formed, the suspect may be jets of superheated gas.

“If you could somehow transport yourself inside this protostar’s collapsing gas cloud, it would be very dark,” said Charles Poteet, lead author of the new study, also from the University of Toledo. “But the tiny crystals might catch whatever light is present, resulting in a green sparkle against a black, dusty backdrop.”

Located in the constellation of Orion, protostar HOPS-68 shares its forsterite crystals with a host of terrestrial souces, too. The forsterite crystal rain chemical compositions belongs to the olivine family of silicate minerals. Not only is it found in meteorites, but it’s part of common Earthly deposits, such as a periodot gemstone and the green sand beaches of Hawaii. In space you’ll find it in remote galaxies and NASA’s Stardust and Deep Impact missions both located the crystals in their close-up studies of comets. But it takes a mighty furnace to forge forsterite.

“You need temperatures as hot as lava to make these crystals,” said Tom Megeath of the University of Toledo in Ohio. He is the principal investigator of the research and the second author of a new study appearing in Astrophysical Journal Letters. “We propose that the crystals were cooked up near the surface of the forming star, then carried up into the surrounding cloud where temperatures are much colder, and ultimately fell down again like glitter.”

While the presence of olivine might be new, capturing the forsterite signature has occurred before – spotted in the swirling, planet-forming disks that surround young stars. What’s unusual is finding it in such at cool temperature… about minus 280 degrees Fahrenheit (minus 170 degrees Celsius). This leads researchers to believe the crystals are cooked below then “served up” in the outer structure. This line of reasoning might also explain why comets also contain the same minerals. As the rocky travellers move through infant solar systems, they collect the crystals where they have moved away to cooler climes.

Could this be true of what we know of our own solar system’s formation? Poteet and his colleagues say it’s plausible, but speculate that jets might have lifted crystals into the collapsing cloud of gas surrounding our early sun before raining onto the outer regions of our forming solar system. Eventually, the crystals would have been frozen into comets. The Herschel Space Observatory, a European Space Agency-led mission with important NASA contributions, also participated in the study by characterizing the forming star.

“Infrared telescopes such as Spitzer and now Herschel are providing an exciting picture of how all the ingredients of the cosmic stew that makes planetary systems are blended together,” said Bill Danchi, senior astrophysicist and program scientist at NASA Headquarters in Washington.

Original story source can be found at JPL News.