Entire Star Cluster Thrown Out of its Galaxy

Cambridge, MA -

The galaxy known as M87 has a fastball that would be the envy of any baseball pitcher. It has thrown an entire star cluster toward us at more than two million miles per hour. The newly discovered cluster, which astronomers named HVGC-1, is now on a fast journey to nowhere. Its fate: to drift through the void between the galaxies for all time.

"Astronomers have found runaway stars before, but this is the first time we've found a runaway star cluster," says Nelson Caldwell of the Harvard-Smithsonian Center for Astrophysics. Caldwell is lead author on the study, which will be published in The Astrophysical Journal Letters and is available online.

The "HVGC" in HVGC-1 stands for hypervelocity globular cluster. Globular clusters are relics of the early universe. These groupings usually contain thousands of stars crammed into a ball a few dozen light-years across. The Milky Way galaxy is home to about 150 globular clusters. The giant elliptical galaxy M87, in contrast, holds thousands.

It took a stroke of luck to find HVGC-1. The discovery team has spent years studying the space around M87. They first sorted targets by color to separate stars and galaxies from globular clusters. Then they used the Hectospec instrument on the MMT Telescope in Arizona to examine hundreds of globular clusters in detail.

A computer automatically analyzed the data and calculated the speed of every cluster. Any oddities were examined by hand. Most of those turned out to be glitches, but HVGC-1 was different. Its surprisingly high velocity was real.

"We didn't expect to find anything moving that fast," says Jay Strader of Michigan State University, a co-author on the study.

How did HVGC-1 get ejected at such a high speed? Astronomers aren't sure but say that one scenario depends on M87 having a pair of supermassive black holes at its core. The star cluster wandered too close to those black holes. Many of its outer stars were plucked off, but the dense core of the cluster remained intact. The two black holes then acted like a slingshot, flinging the cluster away at tremendous speed.

HVGC-1 is moving so fast that it is doomed to escape M87 altogether. In fact, it may have already left the galaxy and be sailing out into intergalactic space.

Big Bang thumbprint may unlock universal truth




A strange new image of the Milky Way is promising to reveal hidden details about our galaxy and pave the way to a better understanding of how the universe was born, astronomers say.

The image, assembled with data from the Planck satellite and released on Tuesday by the European Space Agency, depicts a wraparound view of the Milky Way.

The satellite was designed to probe the most distant light in the universe not as human eye would see it, but in the microwave part of the spectrum, where signals from the most distant reaches of the universe can be detected. So, instead of the starry band familiar to backyard skywatchers everywhere, the image shows the magnetic orientation of countless microscopic dust particles that pervade the galaxy like a thin veil of smoke and give off microwaves.

To astronomers, the van Gogh-like whorls offer a telltale picture of the magnetic forces that thread through the Milky Way. To everyone else, the picture looks more like – well, a giant thumbprint.

“Your eye will do it to you,” said Peter Martin, interim director of the University of Toronto’ s Dunlap Institute for Astronomy and Astrophysics, and part of the team that created the image.
. . .

A more complete view is expected in October, when Planck will weigh in on the magnetic signature of distant parts of the universe lurking behind this foreground view of the Milky Way. By carefully subtracting the Milky Way’s contribution, the Planck team should have the first chance to confirm or refute a headline-making discovery reported in March of a signal from the birth of the universe, the Big Bang. If confirmed by Planck and other experiments, the Big Bang measurement has been described as one of the most important cosmic finds in over a decade.

The Strange Story Of The Secret Death of Comet Ison



A comet that astronomers predicted would light up our night skies suddenly disappeared one evening last November. Now astronomers have finally worked out how Comet ison died

It was supposed to be the comet of the century. Early last year, astronomers became increasingly excited about a ball of ice and dust that had travelled from beyond the reaches of the Solar System and was heading towards the Sun.

They calculated that this object, Comet Ison, would pass close to the Sun, sweep round behind it and then head towards Earth where it would put on the greatest show of heavenly fireworks in living memory.

But as Ison drifted behind the Sun, something entirely different happened instead. Nothing!

As astronomers watched, Comet Ison brightened dramatically, disappeared behind the Sun and was never seen or heard from again. The comet of the century simply vanished.

So what happened to Comet Ison? Today we get an answer thanks to the work of Zdenek Sekanina at the Jet Propulsion Laboratory in Pasadena and Rainer Kracht. Using unique images taken by a number of NASA spacecraft that monitor the Sun millions of kilometres from Earth, these guys have pieced together the most detailed picture yet of the comet’s dying days.

Their conclusion is that Comet Ison died in full view of the watching astronomers who witnessed the death without realising what they were seeing.

The new data comes from three spacecraft that have been continually photographing the Sun for some years. The first is the Solar and Heliospheric Observatory or SOHO spacecraft, a NASA and European Space Agency craft that was launched in 1995 to the L1 point some 1.5 million kilometres from Earth in the direction of the Sun, where the gravitational fields of both bodies cancel out.

The other two spacecraft are a pair called STEREO A and STEREO B which orbit the Sun ahead of, and behind, the Earth and so provide 3D images of solar storms coming our way.

The Best Meteor Shower of the Year Might Happen on May 24
Meteor showers are fairly regular events in the annual astronomy calendar, but Earth could be in for a surprise on May 24 when it encounters a century-old comet stream that it has never encountered before.

The stream was created by Comet 209P/LINEAR, which was discovered in 2004 by the Lincoln Near-Earth Asteroid Research project, and it just so happens that this year our planet's orbit and comet stream are positioned just right for an interplanetary rendezvous. And if some forecasters are correct, this month could see a celestial fireworks display, potentially even outshining the famous Perseid meteor shower that peaks in August.

Space Telescope Reveals Weird Star Cluster Conundrum

NGC 2024 is a star cluster found in the center of the Flame Nebula, approximately 1,400 light-years from Earth. This observation combines X-ray and infrared data from NASA's Chandra and Spitzer space telescopes, respectively.



We thought we had star formation mechanisms pinned down, but according to new observations of two star clusters, it seems our understanding of how stars are born is less than stellar.

When zooming in on the young star clusters of NGC 2024 (in the center of the Flame Nebula) and the Orion Nebula Cluster, NASA’s Chandra X-ray Observatory teamed up with infrared telescopes to take a census of star ages. Conventional thinking suggests that stars closest to the center of a given star cluster should be the oldest and the youngest stars can be found around the edges.

However, to their surprise, astronomers have discovered that the opposite is true.

“Our findings are counterintuitive,” said Konstantin Getman of Penn State University, lead scientist of this new study. “It means we need to think harder and come up with more ideas of how stars like our sun are formed.”

It is thought that stars form after the gravitational collapse of vast clouds of dust and gas, or nebulae. The densest material can be found at the nebula’s center and, as the thinking goes, will be ripe for the first stars in that nebula to appear. After the first stars in the nebula’s center burst to life with fusion burning cores, the leftover gases in the less dense portions of the nebula will generate stars later on.

After using Chandra data to gauge the stars’ masses and brightnesses, and then combining that data with infrared observations, stellar ages could be calculated. In the case of NGC 2024, the researchers noticed that the stars in the cluster’s core were 200,000 years old, but the stars on the outer edges were much older — around 1.5 million years old. Likewise, the Orion Nebula Cluster hosts stars in its core that are 1.2 million years old and the ones around the edge were 2 million years old.

This discovery has caught astrophysicists on the hop and may turn our understanding of star forming regions on its head.

Colin Pillinger, colorful scientist of failed Mars probe, dies at 70
Colin Pillinger, a colorful British space scientist who sported thick mutton-chop whiskers and became a symbol of national pluck in masterminding a failed search for life on Mars, died Thursday in a Cambridge hospital. He was 70.

Pillinger collapsed in his garden after a brain hemorrhage, his family said in a statement.

The Beagle 2, a 155-pound landing craft that Pillinger developed despite bureaucratic resistance, was lost as it approached the surface of Mars on Christmas Day 2003. Nobody knows whether it burned in the Martian atmosphere, shattered on impact or failed to perform once it landed.

A geochemist with a flair for public relations, Pillinger was philosophical about its demise.
He was a true explorer. - Matthew Golombek, Jet Propulsion Laboratory

"Everyone knew how hard it would be to land on Mars," he told reporters, "however easy it looks in the pub after the third pint."

Outside the pub, there were plenty of skeptics. Beagle 2 was built for an estimated $85 million — a small sum in the world of space exploration. It was designed to analyze Martian soils for signs of life past or present — a task already tried by NASA's Viking landers in the 1970s.

"They came up empty," said Matthew Golombek, a senior research scientist at Jet Propulsion Laboratory and a veteran of Mars projects. "But Pillinger was convinced he had a different way to do it."

"He was a true explorer," Golombek said, adding that a Martian crater had been named Beagle after Pillinger's effort. The Beagle 2 was named after the ship Charles Darwin sailed on his 19th century voyages of exploration.

Pillinger spent seven years on the project, raising private funds and persuading British officials to contribute public money as well. Along the way, he triggered widespread public support with help from the British rock group Blur, creators of an album called "Modern Life Is Rubbish."

Blur also composed a distinctive, nine-note signal that the Beagle was supposed to send to a U.S. Mars Odyssey spacecraft after it landed. The signal was never received. A scan of Mars by a giant radio telescope at Jodrell Bank in England was also futile.

Waiting for word along with Pillinger, the United Kingdom had become "a nation of Beagle-watchers," the Scotsman newspaper said in 2003. "We are rooting for a little, technology-packed entity about the size of a garden barbecue, which has traveled an unfeasible distance against innumerable odds.… He has made us believe in Beagle not as a machine but as a living thing."

. . .

Diagnosed with multiple sclerosis in 2005, Pillinger wheeled around on a motorized scooter. He taught for many years at The Open University, a British distance-learning school, and was still active in space research.

But he was best remembered for his Mars probe.

"Had Beagle 2 survived the landing, Pillinger would have been a national hero," The Guardian newspaper said in 2010. "Had he found chemical evidence of Martian life … he would have become an international superstar.

"He remains a hero anyway," the paper said. "He had a go."

Planet portrait captured by Gemini Planet Imager is the best ever
Powerful camera is designed to find new planets

A crisp portrait of a planet 56 light years away has been captured by a new high-tech planet-hunting camera developed largely by Canadians.

The Gemini Planet Imager snapped an "amazingly clear and bright" image of the gas giant Beta Pictoris b after an exposure of just one minute, said Quinn Konopacky, a University of Toronto researcher who co-authored a new scientific paper describing the feat.

"I was very, very excited," recalled Konopacky of her first time seeing the planet's portrait, in an interview with CBC News Monday.
Beta Pictoris b

The Gemini Planet Imager produces clear images of planets such as Beta Pictoris b (bright spot) by removing glare from the star they orbit (centre). The light from the star has been subtracted from this image, which was published in the journal PNAS. (Gemini Planet Imager/Image processing by Christian Marois, NRC Canada)

Beta Pictoris b is several times larger than Jupiter, the largest planet in our solar system.

The new image and information about the planet teased out of the image data are being published in the journal Proceedings of the National Academy of Sciences this week by an international team led by Bruce Macintosh of Stanford University and Lawrence Livermore National Laboratory in California.

The Gemini Planet Imager, billed as the "world's most powerful exoplanet camera" captured its first portrait of an exoplanet — a planet outside our solar system — shortly after it was installed on the Gemini South telescope in Chile in November.

"It was almost straight out of the box," said Konopacky, who used the data from the instrument to confirm the planet's distance from its star – about the same as the distance between the sun and Saturn.

Giant planet around dwarf star a surprising discovery
First of its kind may reveal new insights about planets and brown dwarfs
A gigantic planet-like object like no other has been found circling a tiny star at a record distance.

The object is a kind of "super Jupiter" – a gas giant about 10 times bigger than the biggest planet in our solar system, says Marie-Eve Naud, a PhD student at the University of Montreal and lead author of a scientific report describing the planet. The study is being published in the Astrophysical Journal this week.

GU PSc b is 2,000 times farther from its star than the Earth is from the sun, 67 times farther than Neptune and 50 times farther than Pluto — more distant than any planet ever discovered by a long shot, said René Doyon, a University of Montreal professor who is Naud's co-supervisor and co-author of the report.

But despite the vast distance between them, the planet is bound to its star via gravity, Doyon told CBCNews.ca. "The planet is actually moving with its star."

The researchers estimate that the planet completes its orbit around the star about once every 80,000 years. The star itself is located about 155 light years away, in the constellation Pisces, and is a small, young one, with just a third the mass of our sun.