In 2010, astronomers discovered four stars, all of which are at least 300 times the mass of the Sun. Prior to their detection, stars with this solar mass were thought to be impossible to exist; not one star that has been accounted for and studied has a mass that exceeds the 150 solar mass limit, which is a universal limit. These four colossal stellar bodies have been the only ones detected in the Universe. Their origin stumped astronomers.

Recently, however, one team of astronomers – Samabaran Banerjee, Raval Kroupa, Seungkyung Oh – from the University of Bonn in Germany determined the cause of the “monster” stars’ existence by creating and using a computer model: Because the stars in the tiny R136 cluster are so close to one another, the binary systems are unusually tight; hence, the intense gravitational tug the stars impose on each in each system caused the stars to smash together and fuse to become their present hyper-massive and luminous selves.

“They start appearing very early in the life of the cluster,” Dr. Banerjee states in Royal Astronomical Society press release. “With so many massive stars in tight binary pairs, themselves packed closely together, there are frequent random encounters, some of which result in collisions where two stars coalesce into heavier objects. The resulting stars can then quite easily end up being as ultramassive as those seen in R136.”

These four stars are located in the Large Magellanic Cloud (LMC), which is one of the closest galaxies to the Milky Way and a hotbed for star formation, harboring approximately ten billion stars. Specifically, their home lies in the R136 star cluster, which is a mere 35 light-years across, in the well-known Tarantula Nebula, the LMC’s most active star formation region.

A star cluster is a group of stars tightly held together by gravity. The number of stars range from a few hundred to several hundreds of thousands. Roughly, there are more than 1000 star clusters in the LMC alone.

For accuracy, the model Banerjee, Kroupa, and Oh produced resembled the R136 region. To calculate the shape of the star cluster, the team utilized the NBODY6 – or “N-body” – integration code developed by Sverre Aaseth, a research scientist of the Institute of Astronomy at the University of Cambridge. The model contained 170,000, which were normal in mass and luminosity (that is, they were stars from the Main Sequence of the Hertzsprung-Russell diagram) and were distributed as the stars were in R136.

For Banerjee, Kroupa and Oh to monitor and analyze how the stars interacted with one another and changed over time, the computer had to solve 510,000 calculations multiple times while taking into account stellar winds, nuclear reactions caused by stellar collisions, gravity, and the result of each collision – all of which happened in the supposed densely packed environment. The N-body code the team used helped speed up these calculations.

Once the calculations were completed, the team concluded that the leviathan stars inhabiting R136 used to be ordinary stars that merged with one another, and that they are not anomalies which had formed outside our knowing of how star’s normally form.

“Not only the upper mass limit but the whole mass ingredient of any newborn assembly of stars appears identical irrespective of the stellar birthplace: the star birth process seems to [still] be universal,” Dr. Kroupa says. “This helps us relax because the collisions mean that the ultramassive stars are a lot easier to explain. The universality of star formation prevails after all.”

The team published their paper in Monthly Notices of the Royal Astronomical Society.

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On April 23 at Seattle’s Museum of Flight, Planetary Resources, Inc. announced and revealed their plans to search for and mine asteroids for their precious metals and water. With this mission, its members hope to provide more resources for the Earth and humans and reduce the cost of space travel. Billions to trillions of dollars can be contributed to the global gross domestic profit.

As for a more intrinsic motivation, Planetary Resources also hopes to advance human exploration in space.

The money and means largely come from the founders and backers of the group, which include Google co-founder and CEO Larry Page, Eric Anderson (who founded Space Adventures, which arranged space flights for millionaires) Ross Perot Jr. (the chairman of the Board of Perot Systems), Charles Simonyi (who was a part of the team that devised Microsoft Office Suite), filmmaker James Cameron, and Peter Diamandis (founder and chairman of the X Prize Foundation).

Asteroids are space junk – leftovers from when the planets in our solar system fully formed. Their sizes range from several meters to over one thousand kilometers across. Composition varies, though they are mostly made of metals, some of which are present on Earth (“common” ones such as iron and nickel) and some of which are rare on our planet (platinum, for example.) Some asteroids consist of a significant amount of frozen water along with metals.

“Everything we hold of value on Earth — metals, minerals, energy, water, real estate — are literally in near-infinite quantities in space,” Diamandis tells ABC News.

To conserve time, money, and fuel, Planetary Resources plans to mine asteroids near Earth. Thousands possibly float nearby – many of them too small to be detected. Most that will be mined would be more reachable than the Moon since Earth’s gravitational tends to capture smaller space objects, including asteroids.

The mission is divided into sections. Before getting straight to the mining, the group will first build a low-orbiting telescope that will be able to sieve out the asteroids that show the most promise for harvesting (ten percent of over a thousand). The approximate launch date has not yet determined.

Then comes the actual mining. Subsequent to finding the asteroids via telescope, the group will launch space probes containing unmanned robots, which will be sent out by rocket boosters built by private American companies, by the Russians, or by any other source willing to build them for affordable prices.

As Phillip Plait in writes in his blog “Bad Astronomy,” volatiles (oxygen, nitrogen, and water) will be garnered primarily for the sake of having additional resources. The water will either be converted into hydrogen for rocket fuel and oxygen, or it can be broken down to its basic elements for easier and cheaper transport.

After the volatiles, the robots will mine for the precious metals: platinum, palladium, iridium, and ruthenium, and others, all of which are difficult to access on Earth and only exist on the planet because of impacts from asteroids.

“When the availability of these metals increase[s], the cost will reduce on everything including defibrillators, hand-held devices, TV and computer monitors, catalysts,” Diamandis continues. “And with the abundance of these metals, we’ll be able to use them in mass production, like in automotive fuel cells.”

To further save costs, the robots will have the option of storing the metals and water in supply depots in space instead of bringing to resources back to Earth straight away.

Is Planetary Resources’ plan is completely ludicrous? Not really. Mining asteroids is not is not a novel concept. Plait continues writes that he thinks “getting to the asteroids will do just fine,” and to American astrophysicist Neil DeGrasse Tyson, who recently appeared on the Daily Show, the idea is “not bulls#*t.”

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For decades, dark matter and its nature and location have remained elusive to cosmologists. Recently, a team of astronomers conducted a study to locate the mysterious substance, but the results show that there is not as much dark matter as previously theorized.

“Our calculations show that it should have shown up very clearly in our measurements. But it was just not there!” Christian Moni Bidin of the Astronomy Department at la Universidad de Concepción in Chile says in the European Southern Observatory (ESO) press release. Moni Bidin also headed the study and was the lead author of the team research paper, published in The Astrophysical Journal.

Dark matter is impossible to be seen or detected. It constitutes 74% of the mass in the Universe. How it is distributed around the Universe is unknown. Astronomers believe that dark matter is what causes and exerts the gravitational force around objects made of normal matter (i.e. everything that is not dark matter or dark energy), such as planets, stars, and galaxies.

In the past, astronomers considered that one certain location of dark matter would be around galaxies: a model known as the Standard Halo Model demonstrates how galaxies form and evolve. This model also states that they rotate as quickly as they do due to dark matter, which is thought to collect around the galaxies as a halo.

Working with the 2.2-meter MPG/ESO telescope at ESO’s La Silla Observatory in Chile, the team produced a model in hopes of finding the amount, mass, density, and distribution of dark matter around the Sun (the nearest best bet for finding the substance) and our very own galaxy (the Milky Way). Utilizing a hypothesized amount of dark matter based on a past model, they measured the motions of hundreds of stars (sometimes created from the influence of dark matter) as far as 13,000 light-years away from the Sun.

But what the team observed was a lack of dark matter instead; the conjectured density was significantly lower. “The mystery of dark matter has just become even more mysterious,” Moni Bidin states.

He and his colleagues will further investigate and analyze their results. According to their paper, if matters are consistent, the distribution of dark matter would have to

“reconcile the results with the DM paradigm. The interpretation of these results is thus not straightforward. We believe that they require further investigation and analysis, both on the observational and the theoretical side, to solve the problems they present.”

“Despite the new results,” Moni Bidin continues, “the Milky Way certainly rotates much faster than the visible matter alone can account for. So, if dark matter is not present where we expected it, a new solution for the missing mass problem must be found.”

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For years, astronomers have known that Sun-like stars lose most of their mass as they transition to the red giant stage, but this occurrence remained unexplainable. That is, until an international team of astronomers believes that they have solved the mystery. This discovery can shed light on stellar evolution and, more specifically, how stars age.

When stars like our Sun turn into red giants, they shed off their outer shells of gas and expand and become hundreds of times larger. Stars have “atmospheres,” which consist of powerful winds of gas and dust (which makes up much of a stars’ mass) that the stars emanate, and during their transition, the winds become 100 million times more violent. These “superwinds” occur for 10,000 years – the length of time during which usually red giants live – and cause stars to lose more than half their mass or as much so that only their cores remain.

What causes the “superwinds” has remained elusive for astronomers. Before, it had been thought that the amount of light from the red giants (which are considerably bright for main sequence stars) was absorbed by the dust grains, which were then pushed out by the light. However, all the models that were produced did not coincide with this theory.

The team consists of astronomers from the University of Manchester, Oxford and Macquarie University, University of Sydney, Australia, Paris-Diderot University, and New South Wales. Using the European Southern Observatory’s (ESO) Very Large Telescope (VLT) in northern Chile, the team looked at dying stars with a powerful resolution that allowed them to see the stars’ winds. They were surprised to see how many dust grains whirled around and how large they were. However, they were no bigger than grains of sand, but they were large for their size.

Using this information, the team was able to discover that these dust grains acted as mirrors, reflecting light from other stars. Since the grains remain cold, the star is able to push them out at 10 kilometers per second (20 million miles per hour).

“The dust and sand in the superwind will survive the star and later become part of the clouds in space from which new stars form,” Professor Albert Zijlstra, from the University of Manchester’s Jodrell Bank Observatory, said in the University of Manchester’s news release.

“The sand grains at that time become the building blocks of planets,” he continued. “Our own Earth has formed from star dust. We are now a big step further in understanding this cycle of life and death.”

Now that the mystery of superwinds has been solved, there is another for astronomers to figure out: how these dust grains form and are able to exist at their large size so close to the stars.

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Using BOSS (Baryon Oscillation Spectroscopic Survey), a component of the third Sloan Digital Sky Survey from the Lawrence Berkeley National Laboratory in California, scientists have produced the most accurate measurements of when dark energy arose and caused the universe to accelerate its expansion.

Martin White, of Berkeley Lab’s Physics Division states in the press release, “BOSS’s first major cosmological results establish the accurate three-dimensional positions of 327,349 massive galaxies across 3,275 square degrees of the sky, reaching as far back as redshift 0.7 – the largest sample of the universe ever surveyed at this high density.” White is a professor of physics and astronomy at the University of California at Berkeley, and chair of the BOSS science survey teams.

The notion that the universe is expanding came about in the 1920s, when American astronomer Edwin Hubble discovered that all of the galaxies whose light shift he measured had produced a red shift– they were moving away from the Earth. The universe is continuously accelerating in its expansion.

Accelerated expansion was announced only fourteen years ago. Astronomers believe that a mysterious force called dark energy is the cause of this accelerated expansion, which is believed to have first occurred seven billion years ago. Presently, dark energy makes up nearly 75% of the universe’s total mass and energy.

Since the proposal of dark energy, the idea of it and when it came about precisely remained elusive. But just last week, the group of scientists at Berkley created the most precise map of dark energy, which looks billions of years into the past.

In order to create a map of dark energy, and to determine when dark energy caused the universe to suddenly accelerate expansion, the team of scientists working with BOSS produced precise measurements of the distances between each of the hundreds of thousands of galaxies, while also analyzing the galaxies’ red shifts, which allowed them to calculate the rate of expansion. To determine the distances, BOSS used a technique known as baryon acoustic oscillation.

Baryon acoustic oscillation occurs when baryons (i.e. “ordinary” matter) cluster due to the pressure of sound waves that moved through the universe when the universe was still very young (not even 400,000 years old) and hot and having varied densities because of the mixture of light and matter.

The universe has not always been expanding; rather, the expansion has been slowing down due to the pull of gravity the universe placed on itself. While BOSS was creating the map, it was able to pinpoint when exactly dark energy suddenly “turned on,” and accelerated expansion: six billion years after the universe came into existence.

The map may produce insight into dark energy and what its nature is, and it can also help astronomers understand the structure of the universe, and its expansion rate.

“For the past 13 years, we’ve had a simple model of how dark energy works,” David Schlegel of the U.S. Department of Energy’s Lawrence Berkeley National Laboratory in California, BOSS’ principal investigator tells Space.com. “But the truth is, we only have a little bit of data, and we’re just beginning to explore the times when dark energy turned on. If there are surprises lurking out there, we expect to find them.”

Image Courtesy of   https://www.facebook.com/BerkeleyLab

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In 2007, two super-Earths known as Gliese 667 C and Gliese 581d were discovered orbiting red dwarfs in the habitable zone, an area in which a planet is able to have surface temperature in order to liquid water. Recently, results from a study suggest these planets plus smaller, rocky ones are quite common in our galaxy and orbit red dwarfs by the tens of billions.

The study was conducted by an international team of scientists a part of the HARPS (High Accuracy Radial velocity Planet Search), ESO’s (European Southern Observatory) planet finder. HARPS’s mission is to detect planets beyond the solar system. HARPS especially aims to discover planets that are in the habitable zone.

In order to calculate the largest amount of Earth-like planets that could exist in the Milky Way, HARPS studied the most common type of star in the galaxy: red dwarfs. Red dwarfs are small, cool, and faint in luminosity in comparison to the Sun. Because they spend less energy than other types of stars, they are long-lived and, therefore, are the most common. Approximately 160 billion exist in the galaxy alone, making up a whopping 80% of the total number of stars.

Using a spectrograph from a 3.6-meter telescope from La Silla Observatory in Chile, HARPS chose a sample of 102 red dwarfs from the southern portion of the sky and studied them for six days. HARPS detected nine super-Earths (planets up to ten times the size of the Earth), two of which were inside the habitable zone. Furthermore, 40% of red dwarfs contain super-Earths that are able to sustain water on their surfaces.

Combining their data and the number of stars without planets, and an estimate of how many planets could be discovered, HARPS was then able to calculate the total number of planets orbiting red dwarfs and the different types of these planets. In the end, their results illustrated that tens of billions of smaller rocky planets exist in the Milky Way.

100 of these hypothesized planets should exist in the immediate vicinity – around 30 light-years – of the Sun (smaller planets are difficult to detect). Massive gassy planets (around the size of Jupiter and Saturn), on the other hand, were calculated to be rare when it came to orbiting red dwarfs.

Although it is exciting knowing that so many Earth-sized orbit stars in the habitable zone, astronomers are not getting their hopes up of finding life. It would be difficult for life to thrive on planets that orbit red dwarfs: because red dwarfs are cool, the habitable zone is rather close, leaving any planets close to the red dwarf to be bombarded with flares of ultraviolet rays and X-rays, making the planets not habitable after all. But that does not daunt astronomers of thinking that any of these small worlds could harbor life.

“Now that we know that there are many super-Earths around nearby red dwarfs,” Xaiver Delfosse, a member of the team tells ESO, “we need to identify more of them using both HARPS and future instruments. Some of these planets are expected to pass in front of their parent star as they orbit — this will open up the exciting possibility of studying the planet’s atmosphere and searching for signs of life.”

A detailed report of HARPS experiment and results can be found here.

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A team of astronomers who had been creating a survey of stars at the Max-Planck Institute for Astronomy in Heidlberg, Germany have detected a planetary system – 375 light-years away in the constellation Cetus – that is nearly as old as the universe.

The star in the system, designated HIP 11952, is estimated to be 12.8 billion years old, having formed just a billion years after the Big Bang. Our system, by comparison, is only 4.6 billion years old. Two gas giant planets, HIP 11952b and HIP 11952c, each the size of Jupiter, orbit HIP 11952 and have an orbital period of seven days and nine and a half months, respectively.

The age of this system is certainly stunning, but the composition of the HIP 11952 and its planets are what baffles astronomers: they lack the presence of heavy elements (carbon, oxygen, and iron, for example), contradicting a major aspect of the Accretion theory.

Basically, the Accretion theory describes how solar systems are born and develop, but it also states that planets need a high concentration of heavy elements to form. Many planets that astronomers have studied before the discovery of the HIP 11952 system have all been made of many heavy elements. Even the gas giants in our own solar system contain them – mostly metals in their cores, which need these elements in order to form.

However, shortly after the Big Bang, the lighter elements (hydrogen and helium) dominated the universe. Stars were just beginning to form. Only when these first stars went nova did heavy elements exist, but this must have occurred billions of years following the Big Bang, considering the average lifespan of stars.

Despite the contradiction brought forth by the HIP 11952 system, the Accretion theory is still backed-up by evidence of other planets – largely detected by the NASA spacecraft Kepler – that are composed of heavier elements. These planets and their parent stars, however, are young in comparison with the universe’s age.

Nonetheless, the fact that HIP 11952b, and HIP 11952c exist proves that planets are able to form without the presence of heavy elements and, therefore, have astronomers considering new possibilities of how planets come into being. To solve the Accretion theory issue, they would need to further find and study older and metal-poor planets.

“We would like to discover and study more planetary systems of this kind,” Anna Pasquali tells Huffington Post. Pasquali is a co-author of the team’s paper and is from the Center for Astronomy at Heidelberg University (ZAH). “That would allow us to refine our theories of planet formation. The discovery of the planets of HIP 11952 shows that planets have been forming throughout the life of our Universe.”

According to their paper, the team accounts for the lack of heavy elements and HIP 11952’s long age by surmising that HIP 11952 is a dwarf star, a type of star that has low metallicity and a long lifespan.

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A team of astronomers from the University of Leicester in the United Kingdom and Monash University in Australia have collaborated to put together a new theory that explains how black holes grow to be massive so quickly. With this theory, astronomers and astrophysicists are closer to understanding the nature of black holes.

These outer space oddities are born as the result of a star’s death: when a star collapses upon itself and continues to do so until it becomes a tiny point in space-time. A black hole’s mass is highly compressed, so its gravity is large enough to distort time.

Black holes eat anything and everything: stars, nebulas, planets, space debris, and even light, all of which spiral into the tiny point known as the event horizon. Black holes are hundreds to billions times more massive than the sun. Many galaxies contain supermassive black holes at their centers, including our very own Milky Way.

No one can observe black holes because they cannot be seen (they absorb all light and do not reflect any), but evidence for their presence can be located in distortions in space and light. Smaller black holes are usually found in binary systems, in which the black hole slowly eats away at its companion star.

Most black holes have been feeding since the early years of the Universe. While eating, a disk of gas and other materials (called the accretion disk) forms around them, slowing down their munching and growing time. Astronomers and astrophysicists have determined that certain black holes can grow considerably by eating or crashing into each another to create one massive black hole, and supermassive black holes are usually the result of galaxies colliding. These collisions, though, are quite rare.

Still, the nature of other large black holes cannot be explained. How do other black holes – those that do not collide with anything and that are not in any binary systems – grow to be so big in such a little amount of time? Usually, when black holes feed, a disk (called the accretion disk) of gas and other materials forms around them. This accretion disk is what slows down their munching and growing time.

The astronomers that are part of the research team have developed a theory to account for this mystery. They created computer simulations of a black hole that have two accretion disks orbiting it at different angles. As the simulations continue over time, the disks eventually spread, then collapse. This collapse allows the black hole to swallow heaps of produced gas and enables it to grow 1,000 times faster, according to the University of Leicester press release.

“If two guys ride motorbikes on a Wall of Death, and they collide, they lose the centrifugal force holding them to the walls and fall,” Andrew King clarified. King, one of the astronomers that is part of the team, is from the Department of Physics and Astronomy at the University of Leicester.

The team will publish their research in the Monthly Notices of the Royal Astronomical Society. Their simulations can be found here.

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On March 17th, NASA’s spacecraft MESSENGER revealed surprising details about Mercury’s interior and topography, changing astronomers’ understanding of the small planet and how it was formed.

MESSENGER (MErcury Space Surface ENvironment, GEochemistry, and Ranging) is the first spacecraft sent to orbit and study Mercury, which orbits the Sun a mere 36 million miles away. It’s the innermost and hottest planet in our solar system. MESSENGER was launched in August 2004. Before traveling to Mercury, it made a series of flybys around the Earth (once) and Venus (twice).

MESSENGER finally arrived at Mercury on March 18, 2011 and went around three times. Using radio signals, the spacecraft studied Mercury’s gravitational field, magnetic field, topography, internal geological structure, and chemical composition. Because the results of MESSENGER’S flybys around Mercury were so valuable, its mission was extended to last for another year in November 2011.

Mercury’s topography has changed many times since Mercury was fully formed, meaning that there has been a considerable amount of geological activity. For that reason, before studying any of the planet’s internal structure and history, MESSENGER first produced an accurate map of Mercury’s gravitational field using information derived from the planet’s topography and spin state.

Thereafter, two studies were conducted simultaneously, examining Mercury’s internal structure and geography. In one study, the researchers involved with MESSENGER discovered that the planet’s core was much larger than previously thought: it takes up 85 percent of the planet’s radius. Furthermore, it is liquid instead of solid. Previously, scientists assumed that Mercury would have been cooled enough by now for the core to be solid.

Above the core lies an unusual layer that is composed of solid sulphur and iron – a layer not found in the other rocky planets in the Solar System. The outer layers of the internal structure consist of a solid silicate crust and mantle. It is thought that inside the larger liquid core lies a smaller solid core composed of sulphur and iron.

The other study of Mercury’s topography produced other surprising discoveries. When MESSENGER’s Mercury Laser Altimeter (MLA) produced a topographic model of the northern hemisphere and areas in the mid-latitude range, researchers learned that the elevation spread is smaller than similar regions on the Moon and Mars. The area that sticks out the most is lowlands that contain the northern volcanic plains.

Moreover, according to the Carnegie Institute for Science’s press release,

“… the interior plains of Caloris impact basin — 1,550 kilometers (960 miles) in diameter — have been modified so that part of the basin floor now stands higher than the rim. The elevated portion appears to be part of a quasi-linear rise that extends for approximately half the planetary circumference at mid-latitudes. These features imply that large-scale changes to Mercury’s topography occurred after the era of impact basin formation and large-scale emplacement of volcanic plains had ended.”

This new knowledge of Mercury’s internal structure and topography gives insight as to how Mercury formed thermally and how the planet’s magnetic field is generated. Details of the findings of each study from MESSENGER’s mission will appear in two separate papers, which will appear on March 23 in the journal Science.

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Instead of coming back on December 21, 2012 – the infamous apocalyptic date – the newly discovered asteroid 2012 DA14 is not expected to return around February 15, 2013. For now, humanity can breathe easy.

A group of amateur astronomers working at Observatorio Astronómico de La Sagra (La Sagra Sky Survey), located in the Andalusia Mountains of southeast Spain, discovered the asteroid a month ago, on February 22. The group accidently spotted it in an area of the sky where asteroids are not generally seen, and was only able to detect it when it flew by the Earth at a range of seven times the distance from the Earth to the Moon. 2012 DA14 was difficult to notice because of its small size; it has a diameter of around 50 meters (150 feet).

Come February 15, 2013, 2012 DA14 fly past 24,000 km (15,000 miles) away, much closer than most of our commercial satellites orbit the Earth. One would be able to view it with binoculars, but at that distance, the asteroid would not even skim the atmosphere, let alone hit the Earth.

Phil Plait, former Hubble Space Telescope member and astronomy teacher, assures in his blog Bad Astronomy, “In astronomical terms, [that distance] is pretty close, but in real human terms it’s a clean miss.”

The asteroid’s orbit is inclined in comparison to the Earth’s and lasts for 366.24 days, which is extremely close to that of the Earth, being only one day longer. Due to the nature of its orbit, 2012 DA14 will most likely not ever cause an impact – no matter what other sources assert.

Earlier this month, La Sagra joined the European Space Agency’s (ESA) Space Situation Awareness (SSA) program, which searches for hazards in or that will enter Earth’s orbit and cause harm or pose a risk to life, such as (as stated on their website) “remnant man-made space objects, in-orbit explosions and release events, potential impacts of Near Earth Objects, the effects of space weather phenomena on space- and ground-based infrastructure.” Together, La Sagra and SSA will search for asteroids and miscellaneous space objects that may pose as a threat to the Earth.

In addition to keeping track of the smaller asteroid, when 2012 DA14 approaches again, astronomers will jump at the opportunity to study it and measure the gravitational effects of the Earth and Moon that affect it. After 2013, the asteroid is not expected to return until 2020

According to ESA, the SSA program is developing a system of telescopes that will be able to detect any asteroids around the size of 2012 DA14 – just in case.

“I can’t say this strongly enough: asteroid 2012 DA14 is not an impact threat for February 2013,” Plait continues to write. “However, we definitely need to keep our eyes on this guy to see if it poses a threat at some future date.”

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Last Friday, NASA’s Cassini mission detected molecular oxygen ions on Dione- one of Saturn’s moons- indicating that the moon has an atmosphere. The team involved with the mission includes researchers from Los Alamos National Laboratory in New Mexico, the European Space Agency, and the Italian Space Agency, all of which are a part of collaboration with NASA’s Cassini-Huygens mission.

“We now know that Dione, in addition to Saturn’s rings and the moon Rhea, is a source of oxygen molecules,” Robert Tokar, says to NASA. Tokar, the head author of the team’s paper, is a researcher at Los Alamos National Laboratory. “This shows that molecular oxygen is actually common in the Saturn system and reinforces that it can come from a process that doesn’t involve life.”

Cassini, launched in 1997 and arriving on Saturn in 2004, spotted the molecular oxygen ions in a flyby with one of its active sensors, the Cassini Plasma Spectrometer (CAPS) in 2010, when the researchers at Los Alamos were able to first notice them. Prior, the existence of the ions was postulated after NASA’s Hubble Space Telescope detected ozone. Only after Cassini studied Dione during its flyby, was their postulation confirmed.

Dione was discovered by Giovannia Cassini (after which the titular spacecraft was named) in 1684. As one of the 62 moons revolving around Saturn, it is the tiniest, having a diameter of around 1130km (700 miles). Dione is best known for its pockmarked surface, which is composed of a thick layer of solid water ice. Underneath the surface lies a possible layer of liquid water and a small rocky core.

The distance at which Dione orbits Saturn is the same distance as the Earth from the Sun. The tiny moon’s orbital period lasts every 2.7 days. Because Dione is well within Saturn’s magnetosphere, the ions from the magnetosphere bombard Dione’s surface, and molecular oxygen ions are then created.

These ions bounce off and are dispersed around the planet, creating an atmosphere, albeit a very thin one. According to NASA, there is “one [ion] for every 0.67 cubic inches of space (one for every 11 cubic centimeters of space) or about 2,550 per cubic foot (90,000 per cubic meter).”

“The concentration of oxygen in Dione’s atmosphere is roughly similar to what you would find in Earth’s atmosphere at an altitude of about 300 miles,” Tokar states in Los Alamos National Laboratory’s press release. “It’s not enough to sustain life, but—together with similar observations of other moons around Saturn and Jupiter—these are definitive examples of a process by which a lot of oxygen can be produced in icy celestial bodies that are bombarded by charged particles or photons from the Sun or whatever light source happens to be nearby.”

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An international team of astronomers, led by astrophysicist Francesco Tombesi, at NASA’s Goddard Space Flight Center in Greenbelt, Maryland has discovered what causes galaxies to acquire large bulges in their centers: outflows from supermassive black holes that lie in the bulges.

A black hole is an invisible tiny “hole” in space. It is a former star that collapses on its own gravity, which is so strong that nothing, even light, can escape — hence the name “black hole,” coined by physicist John Wheeler in 1967. Black holes feed on objects surrounding them: nebulas, planetary objects, light — anything. Whatever enters a black hole gets spewed out eventually in the form of jets of x-rays and radiation. These jets allow astronomers to view the black hole’s spectrum, which tells them what elements the black hole swallowed and spat out.

Over the years, astronomers have learned that galaxies, even our very own Milky Way, contain supermassive black holes — black holes that are really, really big — at their centers. Surrounding the supermassive black holes are large clouds of gas, where stars are born left and right. The gravity of these black holes also attract fast moving stars, creating the galaxies’ bulges, which then grow large. As to how this is has puzzled astronomers for years.

Tombesi and his colleagues have encountered a distinct kind of “outflow” from the clouds of gas after studying the spectrographs of forty-two galaxies from the All-Sky Slew Survey Catalog from NASA’s Rossi X-Ray Timing Explorer Satellite. In spectroscopy, astronomers look at absorption spectra — essentially pictures of the electromagnetic spectrum — which present light absorbed from the light sources, such as stars, nebulas, galaxies, and, in this case, black holes. With the absorption spectra, astronomers can gauge the light source’s composition of elements by looking for any black lines that vertically cross the spectrum.

While researching the spectra of x-rays from the forty-two galaxies, Tombesi and the team learned that the supermassive black holes absorbed fluorescent iron. They then found out that 40% of these galaxies had such an outflow flow, which suggests that the outflow is common in black holes at the center of galaxies. The x-rays’ wavelengths were shorter than their normal length, indicating that the galaxies were blueshifted (i.e. moving towards us). This outflow was dubbed “ultra-fast outflows,” or UFOs, by Tombesi according to NASA.

“They have the potential to play a major role in transmitting feedback effects from a black hole into the galaxy at large,” Tombesi says in NASA’s press release.

Ultimately, he and his colleauges learned that UFOs halt supermassive black holes’ growth by taking away the mass it would potentially eat. Furthermore, UFOs can slow down or even completely discontinue star formation in the galactic centers by removing gas from the galactic bulge.

Tombesi and his team hope to further study UFOs and their development with Japan’s Astro-H X-ray telescope, which is scheduled to be launched in 2014.

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On February 2, a team of astronomers detected an exoplanet (short for extrasolar planet) located in the habitable zone, a slim area in which a planet must be located, so that it is not too close nor too far away from the star it orbits, thus having a surface temperature that can sustain liquid. This newly discovered exoplanet may be able to sustain water and even life.

Using data from the European Southern Observatory, the W.M. Keck Observatory in Hawaii, and the Carnegie Planet Finder Spectograph at the Magellan II Telescope in Chile, the astronomers – from the University of California in Santa Cruz and the private research organization Carnegie Institution for Science in Washington, DC – found the exoplanet through discerning the gravitational tug it and its parent star impose on each other. The system lies 22 light-years away in the constellation Scorpius.

“This is basically our next-door neighbor,” Steven Vogt tells Space.com. Vogt, one of the members of the team, is an astronomer at the University of California. “It’s very nearby. There are only about 100 stars closer to us than this one.”

“We’ve been explicitly focusing on very nearby stars,” he adds, “because with today’s technology, we could send a robotic probe out there, and within a few hundred years, it could be sending back picture postcards.”

The star, dubbed GJ 667C, is a part of a triple star system. Unlike its companion stars, which are orange K dwarfs, GJ 667C is an M-class dwarf: it is much smaller and less luminous than the Sun and emits infrared light, which is less intense in light and temperature. GJ 667C’s composition is very different from that of the Sun’s, lacking elements heavier than hydrogen and helium such as carbon, iron, and silicon that are needed to form planets.

“We shouldn’t have really expected this star to be a likely case for harboring planets,” says Vogt.

The exoplanet, named GJ 667Cc, is a super-Earth, roughly 4.5 times the size of the Earth. Because of the absence of heavy elements, much of GJ 667Cc’s mass comes from ice and gas. The orbital period of GJ 667Cc measures 28 days, which would seem dauntingly close to us compared to the Earth’s orbital period.

A planet that takes the same amount of time to orbit the Sun (for instance) would roast; however, GJ 667C’s weak temperature and light, and the fact that GJ 667Cc receives 10 percent of the light the Earth receives from the Sun, counterbalance the closeness of the exoplanet, creating a comfortable region in which to dwell.

Furthermore, GJ 667Cc is in the right spot to absorb the same amount of energy that the Earth absorbs from the Sun to have an atmosphere. In the Carnegie Institution for Science press release, Guillem Anglada-Escudé – co-leader of the study and lead writer of the team’s paper that will soon be published in The Astrophysical Journal Letters – states, “This planet is the new best candidate to support liquid water and, perhaps, life as we know it.”

GJ 667Cc has a sibling, GJ 667Cb, which is around the size of the Earth. Unlike GJ 667Cc, GJ 667Cb has a much smaller orbital period. Hence, it is too close and has too high a temperature to sustain liquid.

Only one other exoplanet located in the habitable zone has been discovered before, Kepler-22b, which was detected by the NASA spacecraft Kepler on December 5, 2011. Astronomers believe that Kepler-22b, which is 2.4 times the Earth’s size, may also maintain water and life.

Image Courtesy of  http://www.esa.int

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This week, the National Aeronautics and Space Administration’s (NASA) spacecraft, Kepler, detected eleven planetary systems, which, overall, contain 26 new exoplanets (short for extrasolar planets, which exist beyond out solar system). Located in the Lyra and Cygnus constellations, each system contains two to five planets. The systems have been dubbed Kepler-23, Kepler-24, Kepler-25, Kepler-26, Kepler-27, Kepler-28, Kepler-29, Kepler-30, Kepler-31, Kepler-32, and Kepler-33.

The sizes of the exoplanets range from 1.5 to 5 times the size of Earth to larger than Jupiter. All of them orbit their parent stars closely; none of them lie in the habitable zone, an area in which a planet is not too close or too far away from a star so that it can sustain water and life. Each of their orbits is closer than that of Venus. The farthest exoplanet has years that last fewer than 200 days and the surface temperature of hundreds of degrees.

Kepler primarily detects planets through a process known as transiting, in which it measures a star’s periodic change in brightness generated by a planet crossing its parent star, causing the star’s light to drop a bit in brightness.

The NASA spacecraft was able to find these newer exoplanets by means of measuring Transit Timing Variations (TTVs). With this method, Kepler calculates changes in the acceleration of planets due to the gravitational pull on one another from being so close together. TTVs help Kepler find the more distant – hence fainter – star systems.

“Prior to the Kepler mission, we knew of perhaps 500 exoplanets across the whole sky,” said Doug Hudgins, Kepler program scientist at NASA Headquarters in Washington, in the press release on NASA’s Kepler website.

“Now,” Hudgins continues, “in just two years staring at a patch of sky not much bigger than your fist, Kepler has discovered more than 60 planets and more than 2,300 planet candidates. This tells us that our galaxy is positively loaded with planets of all sizes and orbits.”

Kepler has been in space for nearly three years. Its mission is to search for Earth-like exoplanets that orbit stars in the habitable zone. Ever since its launch in March 2009, Kepler has made numerous momentous findings, especially in the last couple of months.

On December 5, the spacecraft detected Kepler-22b, the first planet to be found in a habitable zone, and on December 20, it discovered the first two Earth-sized exoplanets, Kepler-20e and Kepler-20f. Kepler’s most recent significant detection occurred earlier this month: exoplanets KOI-961.01, KOI-961.02, and KOI-961.03, the tiniest exoplanets thus far.

Based on the diversity of the types of exoplanets, astronomers believe they will attain a better understanding of how planets form.

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Astronomers part of the international collaboration Probing Lensing Anomalies NETwork (PLANET) calculated the approximate number of planets based on statistical analyses from multiple surveys gathered from observatories, institutions, and ground-based telescopes, including NASA’s spacecraft Kepler, the European Southern Observatory (ESO), the Niels Bohr Institute, the Optical Gravitational Lensing Experiment (OGLE), and the Microlensing Observations in Astrophysics (MOA).

PLANET has taken 16 years to find planets, and six to make a statistical hypothesis (from 2002 to 2007). It is estimated that there are at least 100 billion stars in the Milky Way and that each one has 1.6 planets in orbit on average, coming to a total of 160 billion hypothetical planets. This number is much, much higher than the number originally predicted.

Astronomers use three methods to search for planets. The first one is called transiting, in which one observes a stars’ level of brightness. If the level slightly drops, the dip acts as a signal that a planet is crossing the star during its orbit. The second method is the radial-velocity method. When planets orbit a star, the star does not remain stationary.

Rather, it moves in a small circular motion, causing the planet’s gravitational pull. Lastly, the third method is gravitational microlensing. In relation to an observer on Earth, two stars, one in front of the other, seem to form a straight line. The foreground star causes light from the background star to curve, thus magnifying the latter. If there is a slight temporary difference in the light curve from the foreground star, a planet is orbiting the star.

With the former two methods, astronomers can only find low-mass planets closely orbiting stars. They are what the Kepler spacecraft uses to hunt for planets. The third one, on the other hand, is more sensitive: astronomers can find planets of all sizes (from Mercury-sized to Jupiter-sized) and those that are near and far from their parent stars. In addition, planets’ masses can be determined.

“Together,” Uffe Gråe Jørgensen states in the Niels Bohr Institute press release, “the three methods are, for the first time, able to say something about how common our own solar system is.” Jørgensen is the head of the Astrophysics and Planetary Science research group at the Niels Bohr Institute at the University of Copenhagen.

Based on the collected data, astronomers predict that Earth-like planets (small and rocky) are much more common in the galaxy than gas giants like Jupiter. According to Stephen Kane – who is a part of NASA’s Exoplanet Science Institute at the California Institute of Technology in Pasadena, California – in the HubbleSite press release, “This is encouraging news for investigations into habitable planets.”

Ultimately, this new hypothesis significantly increases the probability of the existence of extraterrestrial life, even sentient life.

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Working with the Palomar Observatory near San Diego and the W.M. Keck Observatory in Hawaii and using NASA’s spacecraft Kepler, astronomers from the California Institute of Technology have found three teeny, rocky, extrasolar planets (otherwise known as exoplanets, which lie beyond our solar system).

NASA launched Kepler in 2009 to search for Earth-like planets that orbit stars in the habitable zone, a region colloquially called the “Goldilocks Zone”, in which a planet must not be too close or too far from a star, so that its temperature would be just right to be habitable for life. Kepler uses a method called transiting to accomplish its mission: it sees if any stars have slight dips in brightness caused by a planet, which eventually eclipses its parent star sometime during its orbit.

The freshly discovered planetary system’s star is named KOI-961 (KOI is an acronym for Kepler Object in Question). Approximately 130 light-years from the Earth, KOI-961 is a red dwarf – a pipsqueak of a star compared to the Sun, which is six times larger. KOI-961 is similar to a nearby star, Barnard’s Star, which is also a red dwarf. Astronomers used information about Barnard’s Star to determine KOI-961′s characteristics, which were then used to calculate its companion planets’ sizes.

The planets’ names are KOI-961.01, KOI-961.02, and KOI-961.03 and have the radii of 0.78, 0.73, and 0.57 times that of the Earth, respectively. The smallest, KOI-961.03, is about the size of Mars, and the other two are about the size of Venus. All three do not lie in habitable zones; they orbit their parent star too closely, and one year equals two days.

Due to their incredibly close orbits, they are too hot to form liquid, let alone for life to thrive. Temperatures are hundreds of degrees, with the closest, KOI-961.01, having a surface temperature of nearly 1,000 degrees Fahrenheit (500°C).

This planetary system is the tiniest known to astronomers. John Johnson, assistant professor of astronomy at Caltech and co-author of the team’s paper, states in the Caltech press release, “It’s actually more similar to Jupiter and its moons in scale than any other planetary system. The discovery is further proof of the diversity of planetary systems in our galaxy.”

Red dwarfs are the most common type of star in our home galaxy, the Milky Way, making up eight out of every ten stars. Because of their ubiquity, Kepler may find more planetary systems with red dwarfs as parent stars. “That boosts the chances of other life being in the universe – that’s the ultimate result here,” Johnson says.

In the past, Kepler has found numerous gas giants around the sizes of Jupiter and Neptune. Its most recent discoveries occurred in December 2011, when it detected Kepler-22b, the first planet discovered to orbit in the habitable zone, and Kepler-20e and Kepler-20f, the first Earth-sized exoplanets detected.

The more planets Kepler detects nowadays, the more they become smaller and rockier, it seems. Kepler’s last two discoveries increases the probability that there may be more rocky exoplanets than astronomers thought, thereby, boosting the chance of the existence of extraterrestrial life.

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An international team of astronomers has produced a map that covers a billion light-years worth of dark matter in the universe. Never before has dark matter been mapped on such a large scale.

Two members of the team, Catherine Heymans of the University of Edinburgh and Associate Professor Ludovic Van Waerbeke of the University of British Columbia in Vancouver, Canada, presented their findings at the 119th meeting of American Astronomical Society, held last week.

The project took place at the Canada-France-Hawaii Telescope Lensing Survey (CFHTLensS) in Hawaii and collected data from the Canada-France-Hawaii Telescope Legacy Survey. For more than five years, the team accumulated images of ten million galaxies – six billion light-years away – from four different regions in the sky during each of the seasons. Essentially peering at the universe when it was but six billions years old, they studied  how dark matter warped the light emitted by the galaxies.

The process of producing the map was completed through a method called gravitational lensing, in which bodies (e.g. galaxies, or, in this case, dark matter) are so massive that they curve space-time and distort light, making it travel in a curve, rather than in a line. By studying the distortions of the galaxies’ light, the team was able to determine the structure of the dark matter and plot its distribution.

“It is fascinating to be able to ‘see’ the dark matter using space-time distortion,” says Waerbeke at the American Astronomical society meeting. “It gives us privileged access to this mysterious mass in the Universe which cannot be observed otherwise. Knowing how dark matter is distributed is the very first step towards understanding its nature and how it fits within our current knowledge of physics.”

The universe is more or less a cosmic web of dark matter and galaxies. Dark matter is impossible to be detected by itself, making it seem invisible, though it makes its presence known through warping space-time and light. The mysterious substance makes up a whopping 23 percent of the universe, with dark energy taking up 72 percent and everything else (stars, planets, etc.) only 4 percent.

With creating such a large map of the cosmic web, astronomers and cosmologists are becoming closer to understanding the nature of dark matter and, ergo, a large portion of the universe. Dr. Heymans, a lecturer of physics and astronomy, says, “By analyzing light from the distant Universe, we can learn about what it has travelled through on its journey to reach us.

We hope that by mapping more dark matter than has been studied before, we are a step closer to understanding this material and its relationship with the galaxies in our Universe.”

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In 2009, NASA launched Kepler to search for planets outside the solar system – called extrasolar planets, or exoplanets – that are Earth-sized and have a chance of harboring life. As of December 2011, the spacecraft has discovered 2,326 exoplanets, over a hundred of which are likely candidates to meet the requirements.

A team of astronomers at NASA decided in early January to give Kepler an additional mission of hunting for extrasolar moons, or exomoons. The team believes in the potential existence of exomoons. Natural satellites only survive half the time when they and their companion planets are still undergoing evolution, though the many moons in our solar system increase the possibility.

With this new mission, titled Hunt of Exomoons with Kepler (HEK), Kepler may find life on these moons as well as on exoplanets and help astronomers understand planetary evolution and the formation of natural satellites. Kepler will first look at the exoplanets cataloged thus far to see if any of them have any such natural satellites. The exomoons would have to be similar in size, or larger, than our Moon because they would be easiest for the spacecraft to detect.

It is also possible that exomoons are capable of harboring life. In our solar system, Jupiter’s Europa and Saturn’s Enceladus have liquid water beneath their surfaces. It is not known for sure if these two large moons contain life, though the presence of water heightens the probability as well as the probability that exomoons may be habitable.

Kepler will attempt to search for exomoons through two means: dynamical effects and eclipses features. With dynamical effects, the spacecraft would observe and measure the gravitational effect between the exoplanet and the exomoon (i.e. how much they tug on each other).

The amount of gravitational effects on the two bodies would determine whether or not the system would be a planet-moon system or a binary-planet system (it would be easy for the former to be mistaken with the latter). With eclipse features, Kepler would be on the lookout for solar and lunar eclipses, involving the exomoon, its companion planet, and their star. Kepler would see if the exomoon may make subtle changes in a star’s brightness through eclipsing the star, which would drop a bit in brightness.

Once Kepler finds an exomoon, it would be able to determine its size and mass based on the gravitational effect and eclipse features. Upon discovering the size and mass, it would then calculate the density. Thereafter, the exomoon’s composition can be determined, giving insight as to how to the exomoon formed and, ultimately, revealing the process of planetary evolution.

“Extrasolar moons represent an outstanding challenge in modern observational astronomy,” writes head author David Kipping in the team’s paper. Kipping,  a member of the team at NASA, is an astronomer at the Harvard-Smithsonian Center for Astrophysics in Cambridge, Massachusetts.

“Their detection and study would yield a revolution in the understanding of planet/moon formation and evolution, but perhaps most provocatively, they could be frequent seats for life in the Galaxy.”

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In early January, researchers at the California Institute of California (Caltech) created a computer model that reproduces Titan’s atmosphere and methane cycle, solving Titan’s weather phenomena that were once inexplicable.

Having a surface temperature of approximately -300°F (-183°C), Titan is one of Saturn’s largest moons. It has a thick atmosphere of methane, a gas deadly for humans. Titan, the only other planetary body in the solar system that has large bodies of liquid on the surface, contains lakes and precipitation of liquid methane. For nearly a decade, researchers at Caltech have noticed bizarre geographical settings and meteorological occurrences.

The first was noticed in 2009 by Odel Aharonson, leader of planetary science at Caltech. He noted that the lakes tended to cluster around Titan’s poles, more so in the northern pole than in the southern. This leaves areas around the equator very dry, lacking in clouds, precipitation, and bodies of liquid.

But in 2005, the space probe Huygens observed a presence of deep channels which look carved out by running liquid. Lastly, regions in the middle and around high altitudes contain clouds that cluster during Titan’s summer in the southern hemisphere.

Previously, scientists have created computer models to account for these meteorological mysteries, though none of them were successful. The newer model, which is three dimensional and simulates Titan’s atmosphere for the past 135 Titan years (equivalent to 3000 Earth years), manages to explain the phenomena by reproducing the distribution of clouds and lakes.

According to the newest model, more lakes exist in the northern hemisphere because Titan is farther from the Sun during the summer due to Saturn’s elliptical orbit, and since Titan is at the far end of Saturn’s orbit the, summer is longer in the northern pole. As Tapio Schneider explains in the Caltech press release, “Methane tends to collect in lakes around the poles because the sunlight there is weaker on average.”

Schneider is a co-author of the paper about the simulation’s findings published in the January 5th issue of Nature and is the Frank J. Gilloon Professor of Environmental Science and Engineering. Hence, without much heat from the Sun, the methane is unable to exist in the gaseous state at the north pole and remains in the liquid state.

To account for the second oddity, the model shows that Titan is closer to the Sun during the moon’s southern summer. Consequently, the rains are more intense here than in the northern hemisphere; however, the model further shows that more lakes exist in the north because storms occur more frequently than they do in the south.

This newer model also explains the presence of liquid-carved channels in the parched equator by producing a simulation that shows rain occurring during the vernal and autumnal equinoxes. Even though these rains are rare, they are quite intense: at the time of the equinoxes, Titan’s poles reverse, causing unstable weather patterns.

“The results for the first time give us a unified picture of how Titan’s methane cycle works,” Schneider tells Space.com. “What I find most satisfying is that many seemingly disparate observations – clouds, lakes, dry river beds – can be explained within one sparse and coherent framework.”

In addition to simulating its atmosphere and methane cycle, the model can also predict Titan’s weather several years in advance, similar to how we are able to predict Earth’s. For instance, the researchers have determined that lake levels will rise in the northern hemisphere for the next fifteen years, and over the next two years, more clouds will form at the north pole.

“This is just the beginning,” Scheinder adds. “We now have a tool to do new science with, and there’s a lot we can do and will do.”

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In early December, an international team of astronomers discovered an incredibly fast rotating star, rotating at a radial velocity of 1.6 million km/h (1 million mph), which is approximately 100 times faster than the sun rotates (roughly four times a day). If the star, dubbed VFTS (short for VLT-FLAMES Tarantula Survey) 102, spun any faster, the centrifugal forces would rip it apart.

Working at the European Southern Observatory’s Very Large Telescope at the Paranel Observatory in Chile, the team located VFTS 102 160,000 light-years away from the Earth in the Tarantula Nebula, which is part of the Large Magellanic Cloud, a satellite galaxy of our Milky Way galaxy. They detected the star because its traveling velocity was 30 km/s (70,000 mph) – much faster than those of other stars in the vicinity.

Philip Dufton, lead author of the paper that presents the team’s findings, stated, “The remarkable rotation speed and the unusual motion compared to the surrounding stars led us to wonder if this star had an unusual early life.” Dufton works at the Department of Physics and Astronomy at Queen’s University Belfast, Northern Ireland. “It was suspicious.”

The centrifugal forces of VFTS 102 (which is a blue giant and has twenty-five times the mass and 100,000 times the luminosity of the sun) are so great that the star has an oblate spheroid shape. Furthermore, they cause VFTS 102 to spin out a disk of plasma at its equator.

The team of astronomers speculate that VFTS 102 had a violent past. It may have been part of a binary star system in which it and its companion star closely rotated around each other. VFTS 102′s fast rotation may have come from the two stars being so close together, which could have caused the companion star to stream gas over to VFTS 102.

Another member of the team, Matteo Cantiello, an astrophysicist at the University of California, Santa Barbara, further explains in the university’s press release, “This gas falls onto the companion star, increasing the mass and spinning it up. Similar to a tennis ball spinning fast after being hit by a glancing blow, a star rotates quickly after being hit off-center by the in-falling gas.”

At some point, the companion star went supernova, expelling much of its gas. The intense explosion ejected VFTS 102, which was sent hurdling through space at the current velocity in which it was discovered. Presently, a supernova remnant and pulsar lie near the blue giant. That these two objects are located nearby VFTS 102 serves as evidence that supports the team’s hypothesis, as the supernova remnant and pulsar may belong to the late companion star, which may have collapsed into a neutron star following its exploding.

“This is a compelling story because it explains each of the unusual features that we’ve seen,” Dufton writes. “This star is certainly showing us unexpected sides of the short, but dramatic lives of the heaviest stars.”

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An international research team of astronomers and astrophysicists were originally trying to find and study pulsars with the Kepler space telescope and the Kitt Peak Earth observatory in Arizona. However, the team got more than they bargained for. Later last week, they detected a star with a unusual pulsating rate: intervallic modulations, which occurred every 5.76 and 8.23 hours, caused the star to faintly flicker. Upon further studying, the team found out that these modulations were not produced by the star, and that is when they discovered two earth-sized exoplanets rotating around a red giant star well within its outer envelopes of gas.

“Having migrated so close, they probably plunged deep into the star’s envelope during the red giant phase, but survived,” says Stéphane Charpinet, who is the leader of the team and an astronomer at the University of Toulouse in France.

Before this finding, scientists in general assumed that planets engulfed by a red giant’s outer layers would be incinerated, and it is believed that this is to happen to the Earth since the Sun is fated to become a red giant. Now that these two exoplanets have been discovered, though, it seems that planets are able to endure stars’ transition to a red giant.

The star in question is named KIC 05807616 (also KOI 55, with “KOI” being the acronym for “Kepler Object of Interest”), formerly a main sequence star on the Hertzsprung-Russell Diagram, like our Sun. The two exoplanets, KOI 55-01 and KOI 55-02, revolve around KIC 05807616 less than approximately 900,000 kilometers and approximately one million kilometers, orbiting KIC 05807616 closer than Mercury orbits the Sun. They have the radii of .76 and .87 times the Earth’s respectively, making them the smallest exoplanets detected thus far.

According to another member of the team, Elizabeth ‘Betsy’ Green, an associate astronomer at the University of Arizona’s Steward Observatory, “The friction with the star’s envelope also strips the gaseous and liquid layers off the planet, leaving behind only some part of the solid core, scorched but still there.” This would account for KOI 55-01 and KOI 55-02′s small sizes.

The research team studied KIC 05807616 and found out that it had been transitioning to become a typical red giant, but since the nuclear reactions began occurring in the outer shells rather than in the core, it expanded, shedding its outer layers and jettisoning much of its mass. Due to the fact that KOI 55-01 and KOI 55-02 orbit KIC 05807616 closer than Mercury orbits the Sun, they may have may have helped KIC 05807616 with its transition, causing it to lose mass more rapidly by stripping its outer shells of gas.

The exoplanets ultimately affected KIC 05807616 enough to become a subdwarf B, which, entirely stripped of its outer layers, has the core of a red giant and the luminosity of a main sequence star, but smaller in mass. Upon finishing their research, the team concluded that planets can affect stellar evolution. “We think this is the first documented case of planets influencing a star’s evolution,” Charpinet states.

“We thought we had a pretty good understanding of what solar systems were like as long as we only knew one – ours,” says Green. “Now we are discovering a huge variety of solar systems that are nothing like ours, including, for the first time, remnant planets around a stellar core like this one.”

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Earlier this week, the spacecraft, Kepler, discovered two exoplanets around the size of the earth – the first of their kind – orbiting a sun-like star. Named Kepler-20e and Kepler-20f, these exoplanets are a part of the star system, Kepler-20, which lies 950 light years away from Earth near the constellation, Lyra.

“This discovery demonstrates for the first time that Earth-size planets exist around other stars and that we are able to detect them,” says Dr. Francois Fressin, an astronomer at the Harvard-Smithsonian Center for Astrophysics in Cambridge, Massachusetts.

Launched in 2009, Kepler is a space telescope built and sent by NASA to detect Earth-like exoplanets (also known as extrasolar planets, which are planets that exist outside our solar system) orbiting stars in habitable zones. Its most recent, significant discovery occurred in early December, when it detected the Neptune-sized Kepler-22b, the first of its kind that has been seen orbiting in the “Goldilocks zone” and that might possibly have water and life.

Kepler took a step closer in accomplishing its mission when it detected Kepler-20, Kepler-20e, and Kepler-20f. Kepler-20 is similar to the sun, in that it is a G-type star. It is yellowish, though a bit smaller and cooler. The star contains five planets in total, all of which orbit it closer than Mercury orbits the sun. The three other planets are gas giants, which are about the size of Neptune, and each planet orbits alternating in size.

These newly discovered exoplanets are only Earth-like in their sizes and rocky composition. Kepler-20e orbits its star every 6.1 days, and its temperature is 1400° F. Its diameter, 6900 miles, is 0.87 times the diameter of the Earth’s. Kepler-20f has an orbit of 19.6 days. It has the temperature of 800° F, and it is 1.03 times Earth’s diameter, being 8,200 miles.

Because of their close orbits and high temperatures, these two exoplanets are not able to sustain water, let alone life. For them to have water and life, they have to lie in the “Goldilocks zone,” or the habitable zone, in which a planet cannot be too close or too far (hence, too hot or too cold) from the star it orbits.

Ever since its launch in 2009, Kepler has been detecting hundreds of exoplanets, many of which are not Earth-like, being hostile and sometimes lonely, not orbiting any stars. With its most recent detection of Kepler-22b and of Kepler-20′s two Earth-like planets, Kepler has reached a new landmark, not just in its journey, but in our knowledge of the various kinds of planets that exist in the observable universe.

“This could be an important milestone,” Dr. Fressin states. “I think 10 years, or maybe even 100 years, from now people will look back and ask when was the first Earth-sized planet found. It is very exciting.”

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A pair of two-billion-year-old clouds of gas are providing scientists with new clues about the origins of the universe this week. These recently discovered pockets of “pristine gas” have remained untouched since the time of the Big Bang, and have never been mingled with heavier elements forged by later stars — giving them the lowest measurement of “metallacity” in the universe.

The discovery will help to lend further credence to the Big Bang theory, as researchers have long believed that only the lightest elements in the universe formed immediately after it’s creation. The lack of dense metals in the pristine clouds, which formed just minutes after the initial Big Bang, serves as some of the first hard evidence of the theory’s accuracy.

In an interview with SPACE.com, astronomer Michele Fumagalli of UC Santa Cruz commented;

“It’s actually a very nice confirmation of the theory, because the theory predicts that in the first few minutes after the Big Bang, things like hydrogen and helium were produced and no metals. So, this is the first time that we have a very strong observation and evidence that indeed this theory is correct. It’s good news for cosmology.”

Distant objects in space are able to analyzed from Earth by rays of light that provide a “fingerprint” of the gases they contain, which is how it was discerned that these particular clouds contain only hydrogen and deuterium. The fact that such pockets of the universe exist uncontaminated by heavier elements is sufficient cause to reexamine the way stars disperse metals.

Originally, it was assumed that pristine gas was not locatable by scientists because heavy elements from early stars had been very thoroughly spread throughout the universe. Now that the clouds’ existence has been proven, researchers will be forced reconsider certain aspects of how matter travels through space.

Previous efforts have been made by scientists to find pristine gas, but this is the first successful attempt. An ongoing study of extragalactic gases revealed the clouds by chance near the constellations of Leo and Ursa Major. It is currently unknown how many other examples of pristine gas might exist throughout the universe, but the search is on for cosmologists.

Physicist John O’Meara of Saint Michael’s college was quoted by Discovery News explaining, ”One of our biggest questions in cosmology is how galaxies get the gas they need to form stars, and how they also sent out the remnants of stars into their surroundings.” Some researchers now theorize that pristine clouds may in fact be the source that feeds young galaxies the cold gas to create stars.

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