Space image: Carina Nebula: 14,000+ Stars

The Carina Nebula is a star-forming region in the Sagittarius-Carina arm of the Milky Way that is 7,500 light years from Earth and the Chandra X-Ray Observatory has detected more than 14,000 stars in the region.

Chandra’s X-ray vision provides strong evidence that massive stars have self-destructed in this nearby star-forming region. Firstly, there is an observed deficit of bright X-ray sources in the area known as Trumpler 15, suggesting that some of the massive stars in this cluster were already destroyed in supernova explosions. Trumpler 15 is located in the northern part of the image and is one of ten star clusters in the Carina complex.

The detection of six possible neutron stars, the dense cores often left behind after stars explode in supernovas, provides additional evidence that supernova activity is increasing up in Carina. Previous observations had only detected one neutron star in Carina.

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Possibly the most distant object known

The most distant objects in the universe are also the oldest — or at least that is how they appear to us, because their light has had to travel for billions of years to get here. They are also extraordinarily faint since they are so far away, and only in the last decade have astronomers been able to stretch their vision using the newest telescopes and clever techniques.

One such innovation occurred with the launch of the NASA Swift satellite in 2004; it searches for bursts of gamma-ray emission, called GRBs. These flashes, thought to result from the especially spectacular deaths of massive stars, are the brightest events in the cosmos during their brief (only seconds-long) existence. But because they are so bright, they can be seen even when they are very, very far away.

A large international team of astronomers including CfA astronomers Edo Berger, Alicia Soderberg, and Ryan Foley used the Swift satellite to spot a GRB that rapid, ground-based followup studies determined was possibly the most distant object known (but measurement uncertainties allow a few other candidates to compete for this title). The light from this object has been traveling towards us for about 13.2 billion years, or 96% of the age of the universe. Since the universe is not static but expanding, today this object is much farther away than 13.2 billion light-years – more like about thirty billion light-years.

The scientists were unable to detect any faint trace of the putative galaxy in which this massive star once lived, helping to confirm the great distance of this GRB. Other important details in their new paper confirm that the object is similar to more nearby GRBs, and consequently that – even at this early stage of cosmic life – at least some stars already resembled stars in our local universe.

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Star Found Shooting Water “Bullets”

Seven hundred and fifty light-years from Earth, a young, sunlike star has been found with jets that blast epic quantities of water into interstellar space, shooting out droplets that move faster than a speeding bullet.

The discovery suggests that protostars may be seeding the universe with water. These stellar embryos shoot jets of material from their north and south poles as their growth is fed by infalling dust that circles the bodies in vast disks.

“If we picture these jets as giant hoses and the water droplets as bullets, the amount shooting out equals a hundred million times the water flowing through the Amazon River every second,” said Lars Kristensen, a postdoctoral astronomer at Leiden University in the Netherlands.

“We are talking about velocities reaching 200,000 kilometers [124,000 miles] per hour, which is about 80 times faster than bullets flying out of a machine gun,” said Kristensen, lead author of the new study detailing the discovery, which has been accepted for publication in the journal Astronomy & Astrophysics.

Located in the northern constellation Perseus, the protostar is no more than a hundred thousand years old and remains swaddled in a large cloud—gas and dust from which the star was born.

Using an infrared instrument on the European Space Agency’s Herschel Space Observatory, researchers were able to peer through the cloud and detect telltale light signatures of hydrogen and oxygen atoms—the building blocks of water—moving on and around the star.


“Vampire” Stars Found in Heart of Our Galaxy


The stellar version of vampires—stars that drain life away from other stars—have been discovered for the first time in the heart of our Milky Way galaxy.

Called blue stragglers, these cannibal stars have been spotted in other parts of the Milky Way. They seem to lag in age next to the other stars with which they formed—appearing hotter, and thus younger and bluer.

Astronomers suspect blue stragglers look so youthful because they’ve stolen hydrogen fuel from other stars, perhaps after colliding into their victims.

These cannibal stars are routinely found in dense star clusters, where stars have many chances to feed off each other. Now, however, scientists have found blue stragglers in the Milky Way’s galactic bulge, a dense region of stars and gas surrounding the galaxy’s center.

“For a long time, it was suspected there were blue stragglers in the bulge, but no one knew how many there might be,” said Will Clarkson, an astronomer at Indiana University Bloomington and the University of California, Los Angeles.

“At long last, we’ve shown they’re there.”


The Keeper: The Legend of Omar Khayyam

It wasn’t Omar’s poetry that made him important: It was the Poetry of His Life. (From the Movie “The Keeper: The Legend of Omar Khayyam)

Scene with Daniel Black as young Omar, Sarah Hadaway as Omar’s mother and Rade Serbedzija as Imam Muaffak.

LANGUAGES: Persian and English

Star’s Fourth World Stumps Astronomers

If three’s a crowd, a new planet recently discovered orbiting a sunlike star is really cluttering up its neighborhood.

The new planet is the fourth Jupiter-like world to be found around the young star HR 8799, astronomers announced today. The same team had previously found the other three planets in 2008, when they took a direct picture of the star system.

Of the more than 500 planets discovered to date outside our solar system, most have been found via indirect methods, such as looking for planets’ gravitational tugs on their host stars or for dips in starlight when planets pass in front of their hosts.

The new planet was also found in a direct image of the HR 8799 system. But based on the masses of the planets and their distances from the star, the fourth world challenges current theories of planet formation, according to the study authors.

“This is the first multiplanet system directly imaged so far, so it’s quite a feat,” said lead study author Christian Marois, an astronomer at the Herzberg Institute of Astrophysics in Canada.

“But we are now stuck with four planets [and] we cannot explain their formation and their current locations by any of our models.”


Stars in the Milky Way Move in Mysterious Ways

Rather than moving in circles around the center of the Milky Way, all the stars in our Galaxy are travelling along different paths, moving away from the Galactic center.

This has just been evidenced by Arnaud Siebert and Benoit Famaey, astronomers at the Strasbourg Astronomical Observatory (CNRS/Université de Strasbourg), and by their colleagues in other countries.

This strange behavior may be due to perturbation caused by the central bar and spiral arms of our Galaxy, forcing stars to leave their normal circular course and take an outward path.

Most galaxies, including our own Milky Way, are spiral-shaped and stars are distributed in a thin disk rotating around the galactic center, with areas divided into spiral arms or elliptical regions such as the central bar.

Due to gravity, the spiral arms move through the disk in the form of density waves.  For over twenty years, scientists believed that the potential impact of these density waves on stellar velocities in the Milky Way was insignificant in comparison with the circular motion of the stars in the galactic disk.

This belief has now been blatantly proved wrong by an international team including several researchers from the Strasbourg Astronomical Observatory: near the Earth, stars move towards the exterior of the Galaxy at an average speed of around 10 kilometers per second, which is considerably faster than previously thought.

To reach this conclusion, the team systematically analyzed the velocities of over two hundred thousand stars located within a radius of a little over six thousand light years around the Sun. Using data from the major star survey RAVE (RAdial Velocity Experiment) collected since 2003 by the Australian Astronomical Observatory’s Schmidt telescope, they were able to measure for the first time the radial velocities of hundreds of thousands of stars and determine whether they were moving towards or away from us.

The researchers were thus able to ascertain that the average speed of stars towards the exterior of the Galaxy increases with their distance from the Sun in the direction of the Galactic center, reaching 10 kilometers per second at a distance of 6 000 light years from us (in other words, 19 000 light years from the Galactic center).


How many stars are there? More than you thought

Red dwarf stars are far more common than astronomers have believed — in fact, they may make up 80 percent of the star population, scientists said in a study on Wednesday that triples the number of stars in the universe.

They analyzed the light coming from galaxies known as elliptical galaxies and found they were chock full of these red dwarfs, which are small, cool stars.

“There are possibly trillions of Earths orbiting these stars,” Pieter van Dokkum of Yale University, who led the research, said in a statement. “It’s one reason why people are interested in this type of star.”

The findings, published in the journal Nature, also suggest there is far less dark matter in these galaxies than had been proposed — something that may be good as astronomers understand stars far better than they do dark matter.

“What we already knew was that these galaxies had a lot of unseen matter at their centers,” van Dokkum said in a telephone interview.

“What we didn’t know was whether the matter was dark, this mysterious matters we don’t know much about, or whether it was in the form of stellar bodies.”

The team did spectral analysis, examining the light that comes from the galaxies. Red dwarfs don’t emit enough visible light to be seen from the Earth but they affect the overall glow from a galaxy.

“In these galaxies there are little pieces of the rainbow that are missing, wavelengths that have much less strength than the rest,” van Dokkum said. His team looked for these so-called absorption lines that are known to be made by red dwarf stars.

The data indicated they were abundant.

“We usually assume other galaxies look like our own. But this suggests other conditions are possible in other galaxies,” said Charlie Conroy of the Harvard-Smithsonian Center for Astrophysics, who was also involved in the research.

“So this discovery could have a major impact on our understanding of galaxy formation and evolution.”

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