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.NASA

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.

PHOTOS: Herschel’s Coolest Infrared Hotshots

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.

ANALYSIS: Orion’s ‘Death Stars’ Exterminate Baby Planets

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.

“A key conclusion from our study is we can reject the basic model where clusters form from the inside out,” said coauthor Eric Feigelson, also of Penn State. “So we need to consider more complex models that are now emerging from star formation studies.”

So what’s going on? Is our understanding of stellar mechanics really that wrong? Not necessarily, but star cluster evolution models will certainly need some tweaking.

NEWS: Spitzer Sheds Light on Colony of Baby Stars

The researchers have several possible answers to the conundrum. First, it could be that there’s simply more gas in the center of the star-forming nebula that allows stars to be born long after stars have finished forming in the depleted edges of the cluster. That would make it appear that there are older stars at the edges than in the core. Secondly, stars that formed first in the cluster’s center have more time to gravitationally interact with other stars, causing them to be slingshotted to the cluster’s edges, leaving younger stars behind.

Thirdly, the young stars could be formed in the cluster’s center by filaments of gas and dust that fall into the center of the cluster. This could be envisaged as a sort of “conveyer belt” effect where older stars are replaced in the core by new stars being created by in-falling material.

Whether one of these theories is the correct one (or whether it’s a combination of all three) remains to be seen, but this is certainly a reminder that the physics of star formation is far from being fully understood; it is an exciting and evolving field of study that turns up its fair share of surprises.

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Asteroid hunters want to launch private telescope

LOS ANGELES (AP) — Who will protect us from a killer asteroid? A team of ex-NASA astronauts and scientists thinks it's up to them.

In a bold plan unveiled Thursday, the group wants to launch its own space telescope to spot and track small and mid-sized space rocks capable of wiping out a city or continent. With that information, they could sound early warnings if a rogue asteroid appeared headed toward our planet.

So far, the idea from the B612 Foundation is on paper only.

Such an effort would cost upward of several hundred million dollars, and the group plans to start fundraising. Behind the nonprofit are a space shuttle astronaut, Apollo 9 astronaut, former Mars czar, deep space mission manager along with other non-NASA types.

Asteroids are leftovers from the formation of the solar system some 4.5 billion years ago. Most reside in the asteroid belt between Mars and Jupiter but some get nudged into Earth's neighborhood.

NASA and a network of astronomers routinely scan the skies for these near-Earth objects. And they've found 90 percent of the biggest threats — asteroids at least two-thirds of a mile across that are considered major killers. Scientists believe it was a 6-mile-wide asteroid that wiped out the dinosaurs.

But the group thinks more attention should be paid to the estimated half a million smaller asteroids — similar in size to the one that exploded over Siberia in 1908 and leveled more than 800 square miles of forest.

"We're playing cosmic roulette. We're flying around the solar system with these other objects. The laws of probability eventually catch up to you," said foundation chairman and former shuttle astronaut Ed Lu.

Added former Apollo 9 astronaut Rusty Schweickart: "The current priority really needs to be toward finding all of those asteroids which can do real damage if they hit or when they hit. It's not a matter of if; it's really a matter of when."

Asteroids are getting attention lately. NASA nixed a return to the moon in favor of a manned landing on an asteroid. Last month, Planetary Resources Inc., a company founded by space entrepreneurs, announced plans to extract precious metals from asteroids within a decade.

Since its birth, the Mountain View, Calif.-based B612 Foundation — named after the home asteroid of the Earth-visiting prince in Antoine de Saint-Exupery's "The Little Prince" — has focused on finding ways to deflect an incoming asteroid. Ideas studied include sending an intercepting spacecraft to aiming a nuclear bomb, but none have been tested.

Last year, the group shifted focus to seek out asteroids with a telescope.

It is working with Ball Aerospace & Technologies Corp., which has drawn up a preliminary telescope design. The contractor developed NASA's Kepler telescope that hunts for exoplanets and built the instruments aboard the Hubble Space Telescope.

Under the proposal, the asteroid-hunting Sentinel Space Telescope will operate for at least 5 1/2 years. It will orbit around the sun, near the orbit of Venus, or between 30 million to 170 million miles away from Earth. Data will be beamed back through NASA's antenna network under a deal with the space agency.

Launch is targeted for 2017 or 2018. The group is angling to fly aboard SpaceX's Falcon 9 rocket, which made history last month by lifting a cargo capsule to the International Space Station.

Experts said the telescope's vantage point would allow it to spy asteroids faster than ground-based telescopes and accelerate new discoveries. NASA explored doing such a mission in the past but never moved forward because of the expense.

"It's always best to find these things quickly and track them. There might be one with our name on it," said Don Yeomans, who heads the Near-Earth Object Program at NASA's Jet Propulsion Laboratory, which monitors potentially dangerous space rocks.

Aside from the technological challenges, the big question is whether philanthropists will open up their wallets to support the project.

Nine years ago, the cost was estimated at $500 million, said Tim Spahr, director of the Minor Planet Center at Harvard University who was part of the team that came up with the figure for NASA.

Spahr questions whether enough can be raised given the economy. "This is a hard time," he said.

The group has received seed money — several hundreds of thousands of dollars — from venture capitalists and Silicon Valley outfits to create a team of experts. Lu, the foundation chair, said he was confident donors will step up and noted that some of the world's most powerful telescopes including the Lick and Palomar observatories in California were built with private money.

"We're not all about doom and gloom," Lu said. "We're about opening up the solar system. We're talking about preserving life on this planet."

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Online:

NASA's Near-Earth Object Program: http://neo.jpl.nasa.gov

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Alicia Chang can be followed at http://www.twitter.com/SciWriAlicia

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New telescope to be in South Africa, Australia

PRETORIA, South Africa (AP) — Australia and South Africa will share hosting of a giant radio telescope made up of thousands of separate dishes and intended to help scientists figure out the make-up of the universe, the international consortium overseeing the project announced.

South Africa led an African consortium that included Botswana, Ghana, Kenya, Madagascar, Mauritius, Mozambique, Namibia and Zambia, and telescopes will be erected in all its partners. In South Africa, dishes will be added to a remote site in the arid Karoo desert where a smaller radio telescope project already is underway.

South Africa and Australia, which partnered with New Zealand in bidding for the project, had competed fiercely. South Africa claimed victory Friday, saying it got two of the projects three major components.

"We may feel slightly disappointed that we didn't get the whole thing. But I think one should emphasize that we did get most of it," said Justin Jonas, the chief South African scientist on the project. "Two-thirds of the biggest instrument in the world is still the biggest instrument in the world."

South Africa's science minister Naledi Pandor and scientists who had prepared the country's bid celebrated with an Africa-shaped cake at a news conference in South Africa's capital.

"This marks a real turning point in Africa, where we are becoming a destination for science and engineering, and not just a place where there are resources and tourism opportunities," Jonas added.

Australia also welcomed the split decision.

"It is an outstanding result for the Australia-New Zealand bid after many years of preparation and an intensive international process," said Sen. Chris Evans, Australia's science minister.

The Square Kilometer Array telescope will be 50 times more sensitive and scan the sky 10,000 times faster than any existing telescope. It requires huge open spaces with very few humans.

John Womersley, chair of the consortium's board, said the telescope will help scientists answer key questions: "Where do we come from? Where are we going? What is this universe we live in?"

"We don't understand what 96 percent of our universe is made of," he said.

The organization said dividing construction of the telescope will "maximize on investments already made by both Australia and South Africa."

Womersley said that splitting construction between the two nations will likely add around 10 percent to the €350 million ($439 million) cost of the first phase of building the giant telescope. But he said there would be a payoff for astronomers.

"It delivers more science in phase one. The capabilities of this instrument are greater than the original design," Womersley said.

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Associated Press writer Mike Corder contributed from Amsterdam.

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Fund Raising Effort Reopens SETI Institute's Allen Telescope Array (ContributorNetwork)

The Allen Telescope Array, a dedicated cluster of radio telescopes dedicated to the Search for Extraterrestrial Intelligence, is back in business thanks to a fund raising effort conducted by the SETI Institute.

The ATA, which was built thanks to private funding from Microsoft executive Paul Allen, was forced to shut down through lack of funding. The fund raising effort, according to Space.Com, has raised the $200,000 necessary from about 2,000 donors to reopen the facility and to recommence the search for ET's radio signals. One of the donors, coincidentally, was actress Jodi Foster, who played an astronomer who finds signals from aliens in the film "Contact," based on the novel by Carl Sagan.

SETI or the Search for Extraterrestrial Intelligence has had a long a storied history, ever since Project Ozma in 1960. SETI has been primarily a privately funded effort since NASA's effort was defunded by the Congress in the mid 1990s. The defunding of NASA's SETI was part of a wave of political attacks on big science projects in the early to mid 1990s that also terminated the Super Conducting Super Collider and almost ended the space station project.

The Allen Telescope Array consists of a 42 small dishes spread out over an area near the Hat Creek Radio Observatory, 290 miles northeast of San Francisco, California. Each dish is 20 feet or 6 meters in diameter, making them relatively small. However the ATA tracks areas of the sky simultaneously to conduct radio astronomy, especially of other galaxies, as well as conducting SETI operations. It is hoped that ATA will eventually consist of 350 dishes, making it one of the most powerful radio astronomy facilities on the planet. In this way the detecting power of the small dishes, when the ATA is eventually completed, would be combined as a "phased array" to make it the equivalent of a single dish 114 meters in diameter and the angular resolution of a dish 700 meters across. The plummeting price of electronics and the relatively small size of the dishes make the ATA a nimble observatory that can track targets in the sky relatively quickly. As technology improves, the dishes, because of their relatively small size, can be more easily upgraded or replaced than a single, large dish.

Besides SETI, ATA is "--being used for radio astronomy observations of our galaxy and other galaxies, gamma ray bursts and transient radio sources, and SETI." The ATA has been in operation since 2007 and has already garnered a great deal of radio astronomy science, including radio images of a number of galaxies.

Mark R. Whittington is the author of Children of Apollo and The Last Moonwalker. He has written on space subjects for a variety of periodicals, including The Houston Chronicle, The Washington Post, USA Today, the L.A. Times, and The Weekly Standard .

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Hubble Telescope Finds Glowing 'Necklace' in Space (SPACE.com)

Talk about bling! A giant "necklace" glowing brightly in space is the centerpiece of a new photo from NASA's Hubble Space Telescope.

The cosmic object, which is appropriately named the Necklace Nebula, is a recently discovered planetary nebula, made up of the glowing remains of an ordinary, sun-like star. The Necklace Nebula is located about 15,000 light-years away in the constellation Sagitta.

Planetary nebulas form when stars similar to our sun deplete their store of hydrogen fuel. The stars' outer layers expand and cool, creating a massive envelope of dust and gas. Radiation flowing out from the dying star ionizes this envelope, causing it to glow. [See Hubble's photo of the Necklace Nebula]

Despite the implications of their name, planetary nebulas have nothing to do with planets. Rather, the term refers to their apparent resemblance to giant planets when they were observed through early telescopes.

The Necklace Nebula consists of a bright ring, measuring 12 trillion miles (more than 19 trillion kilometers) wide. The dense, luminescent knots of gas around the ring resemble the necklace's jewels. [50 Deep Space Nebula Photos]

A pair of stars orbiting close to one another produced this nebula, which is formally known as PN G054.2-03.4. About 10,000 years ago, one of the aging stars ballooned until it engulfed its companion star. The smaller star, though consumed, continued orbiting inside its larger companion, increasing the more massive star's rotation rate.

As a result, the bloated companion star spun so fast that a large part of its gaseous envelope expanded into space. Due to centrifugal force, most of the escaping gas seeped out along the star's equator, producing a ring. The embedded knots are densely packed clumps of gas in the ring.

The stars in the pair are so close — only a few million miles apart, they appear as one bright dot in the center of the ring. The stars are whirling so furiously around each other that they complete a full orbit in a little more than a day.

Follow SPACE.com for the latest in space science and exploration news on Twitter @Spacedotcom and on Facebook.

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Hubble Telescope Marked Highlight of Space Shuttle Program (ContributorNetwork)

Yahoo! News asked its readers and contributors to share their memories of the space shuttle program as it nears its end in July. Below is a story from a contributor.

[Your Voice: Sign up with the Yahoo! Contributor Network to share your thoughts.]

As the final mission of Space Shuttle Atlantis approaches, marking the retirement of NASA's shuttle fleet, many of us are filled with nostalgia. Whether it is the youngest generation, which is just learning about the shuttle this year, or older ones like mine that can still remember debates over the costs of the plan to build a fleet of these ships, everyone has their own unique memories.

My personal favorite memory -- what I believe was the shuttle's finest hour -- was its first successful repair of the Hubble Space Telescope. After Hubble was launched into orbit by Space Shuttle Discovery in April 1990, it soon became clear that it was suffering from a flawed mirror that distorted its much anticipated photos of space. Despite attempts to correct them, it seemed the entire project was a failure. NASA's expertise in space was in question. Nothing seemed to be going right.

I could relate. In the early 1990s, the country was suffering another recession, just as I was finishing school and entering the job market. My relationships with family and friends were changing, and everyone seemed to be getting more cynical about everything. Life was quickly losing its wonder.

Then in December 1993, the newest shuttle of the fleet, Endeavour, embarked on a mission to the Hubble Space Telescope to repair its problems, and enhance its capabilities. I watched every newscast during its mission, and was truly impressed by the complex repairs the shuttle astronauts were doing; replacing gyroscopes, large solar panels, delicate lenses, and computer components. Not an easy job on Earth, much less in space. The mission turned out to be a great success, and Hubble was repaired.

If the space shuttles (and their crews) could successfully repair large objects in space, they could also build new ones.

Now, a little more than 18 years after that mission, the Hubble Space Telescope is still functioning and the International Space Station is now complete. Humanity has its first permanent fixture in space, and just as so many of us knew when Hubble was first repaired, the meaning of the Space Station is far more than scientific study.

If a space station can be built in orbit, a space port can be added to it. So can shipyards, where larger spaceships can ultimately be built. The ISS is our springboard into space, from where (over time) humanity will spread further out in exploration and commerce.

All this was made possible largely thanks to the Space Shuttle. It was already a marvel of invention in itself when it was put into service in the 1980s. It has been a critical tool in the quest to realize that great things can be completed, that dreams are worth having and pursuing, and that life can still be filled with wonder.

To the Space Shuttle Fleet (both past and present), we should wish the following;

Thanks for the memories of the past, and the dreams of the future.

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