SpaceJibe

September 30, 2010

Odds of Life on Newfound Earth-Size Planet ‘100 Percent,’ Astronomer Says

This artist's conception shows the inner four planets of the Gliese 581 system and their host star, a red dwarf star only 20 light years away from Earth. The large planet in the foreground is the newly discovered GJ 581g, which has a 37-day orbit right in the middle of the star's habitable zone and is only three to four times the mass of Earth, with a diameter 1.2 to 1.4 times that of Earth.

This artist's conception shows the inner four planets of the Gliese 581 system and their host star, a red dwarf star only 20 light years away from Earth. The large planet in the foreground is the newly discovered GJ 581g, which has a 37-day orbit right in the middle of the star's habitable zone and is only three to four times the mass of Earth, with a diameter 1.2 to 1.4 times that of Earth.

An Earth-size planet has been spotted orbiting a nearby star at a distance that would makes it not too hot and not too cold — comfortable enough for life to exist, researchers announced Wednesday.

If confirmed, the exoplanet, named Gliese 581g, would be the first Earth-like world found residing in a star’s habitable zone — a region where a planet’s temperature could sustain liquid water on its surface.[Illustration of planet Gliese 581g.]

And the planet’s discoverers are optimistic about the prospects for finding life there.

“Personally, given the ubiquity and propensity of life to flourish wherever it can, I would say, my own personal feeling is that the chances of life on this planet are 100 percent,” said Steven Vogt, a professor of astronomy and astrophysics at the University of California, Santa Cruz, during a press briefing today.

“I have almost no doubt about it.”

His colleague, Paul Butler of the Carnegie Institution of Washington, in Washington, D.C., wasn’t willing to put a number on the odds of life, though he admitted he’s optimistic.

“It’s both an incremental and monumental discovery,” Sara Seager, an astrophysicist at the Massachusetts Institute of Technology, told SPACE.com. Incremental because the method used to find Gliese 581g already has found several planets (all super-Earths, more massive than our own world) outside their stars’ habitable zone, along with non-Earth-like planets within the habitable zone.

“It really is monumental if you accept this as the first Earth-like planet ever found in the star’s habitable zone,” said Seager, who was not directly involved in the discovery.

Vogt, Butler and their colleagues will detail the planet finding in the Astrophysical Journal.

The newfound planet joins more than 400 other alien worlds known to date. Most are huge gas giants, though several are just a few times the mass of Earth.

Stellar tugs

Gliese 581g is one of two new worlds the team discovered orbiting the red dwarf star Gliese 581, bumping that nearby star’s family of planets to six. The other newfound planet, Gliese 581f, is outside the habitable zone, researchers said.

The star is located 20 light-years from Earth in the constellation Libra. One light-year is about 6 trillion miles (10 trillion km).

Red dwarf stars are about 50 times dimmer than our sun. Since these stars are so much cooler, their planets can orbit much closer to them and still remain in the habitable zone.

Estimates suggest Gliese 581g is 0.15 astronomical units from its star, close enough to its star to be able to complete an orbit in just under 37 days. One astronomical unit is the average distance between the Earth and sun, which is approximately 93 million miles (150 million km).

The Gliese 581 planet system now vaguely resembles our own, with six worlds orbiting their star in nearly circular paths.

With support from the National Science Foundation and NASA, the scientists — members of the Lick-Carnegie Exoplanet Survey — collected 11 years of radial velocity data on the star. This method looks at a star’s tiny movements due to the gravitational tug from orbiting bodies.

The subtle tugs let researchers estimate the planet’s mass and orbital period, how long it takes to circle its star.

Gliese 581g has a mass three to four times Earth’s, the researchers estimated. From the mass and size, they said the world is probably a rocky planet with enough gravity to hold onto an atmosphere.

Just as Mercury is locked facing the sun, the planet is tidally locked to its star, so that one side basks in perpetual daylight, while the other side remains in darkness. This locked configuration helps to stabilize the planet’s surface climate, Vogt said.

“Any emerging life forms would have a wide range of stable climates to choose from and to evolve around, depending on their longitude,” Vogt said, suggesting that life forms that like it hot would just scoot toward the light side of that line while forms with polar-bear-like preferences would move toward the dark side.

Between blazing heat on the star-facing side and freezing cold on the dark side, the average surface temperature may range from 24 degrees below zero to 10 degrees Fahrenheit (minus 31 to minus 12 degrees Celsius), the researchers said.

Are you sure?

Supposedly habitable worlds have been found and later discredited, so what makes this one such a breakthrough?

There’s still a chance that further observations will dismiss this planet, also. But over the years, the radial velocity method has become more precise, the researchers point out in their journal article.

In addition, the researchers didn’t make some of the unrealistic assumptions made in the past, Seager said.

For instance, another planet orbiting Gliese 581 (the planet Gliese 581c) also had been considered to have temperatures suitable for life, but in making those calculations, the researchers had come up with an “unrealistic” estimate for the amount of energy the planet reflected, Seager pointed out. That type of estimate wasn’t made for this discovery.

“We’re looking at this one as basically the tip of the iceberg, and we’re expecting more to be found,” Seager said.

One way to make this a reality, according to study researchers, would be “to build dedicated 6- to 8-meter-class Automated Planet Finder telescopes, one in each hemisphere,” they wrote.

The telescopes — or “light buckets” as Seager referred to them — would be dedicated to spying on the nearby stars thought to potentially host Earth-like planets in their habitable zones. The result would be inexpensive and probably would reveal many other nearby potentially habitable planets, the researchers wrote.

Beyond the roughly 100 nearest stars to Earth, there are billions upon billions of stars in the Milky Way, and with that in mind, the researchers suggest tens of billions of potentially habitable planets may exist, waiting to be found.

Planets like Gliese 581g that are tidally locked and orbit the habitable zone of red dwarfs have a high probability of harboring life, the researchers suggest.

Earth once supported harsh conditions, the researchers point out. And since red dwarfs are relatively “immortal” living hundreds of billions of years (many times the current age of the universe), combined with the fact that conditions stay so stable on a tidally locked planet, there’s a good chance that if life were to get a toe-hold it would be able to adapt to those conditions and possibly take off, Butler said.

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Mars, Here We Come! Congress Approves $19 Billion NASA Budget

A vintage logo for NASA, the National Aeronautics and Space Administration. (NASA)

A vintage logo for NASA, the National Aeronautics and Space Administration. (NASA)

Congress passed a vital NASA authorization bill late Wednesday, paving the way for an extra space shuttle flight next year and a new human spaceflight plan that takes aim at missions to an asteroid — and ultimately even to Mars.

The NASA authorization bill approved by the House includes a $19 billion budget in 2011 for the U.S. space agency, and a total of $58 billion through 2013. It paves the way for several NASA projects, among them a new heavy-lift rocket for deep space missions and funding to aid the development of commercial space vehicles for eventual NASA use.

The bill was originally approved by the Senate on Aug. 5. The House opted to vote on the Senate’s NASA authorization bill after running out of time on a compromise version proposed by Congressman Bart Gordon (R-Tennessee) last week. The fiscal year ends Thursday (Sept. 30).

The House officially voted in favor of the bill at about 11:37 p.m. EDT (0337 GMT). The 304-118 decision came just before Congress heads into recess until after the Nov. 2 elections.

President Obama’s new space plan, announced in February, cancelled NASA’s moon-oriented Constellation program set forth by former President George W. Bush and called for more ambitious deep space missions to an asteroid and Mars. The Constellation program was responsible for the Orion space capsules and Ares rockets set to follow the shuttle program.

“Passage of this bill represents an important step forward towards helping us achieve the key goals set by the President,” NASA chief Charles Bolden said in a statement in response to House vote. “This important change in direction will not only help us chart a new path in space, but can help us retool for the industries and jobs of the future that will be vital for long term economic growth.”

Extra shuttle flight, commercial space funds

The NASA authorization bill, S. 3729, officially clears NASA to add one extra space shuttle flight to the two final missions already planned before the shuttle fleet is retired in 2011.

It also allows NASA to extend its role in the International Space Station through at least 2020 and sets aside $1.3 billion over three years to support the development of commercial spacecraft, less than half of the $3.3 billion the White House has requested.

Obama’s space plan tasks NASA to draw on commercial space vehicles to ferry astronauts to and from the International Space Station. Until those commercial vehicles are available, the U.S. would rely on Russian Soyuz craft to fly humans in space and unmanned Russian, Japanese and European freighters to launch cargo.

NASA officials have said the extra shuttle flight would likely fly sometime around June 2011 aboard the Atlantis orbiter. It will deliver large spare parts and cargo to the space station. The space agency chose a veteran four-man crew for this final space shuttle flight earlier this month.

But the extra space mission would not affect the coming Oct. 1 layoffs of nearly 1,400 shuttle workers by NASA contractor United Space Alliance – a joint venture by Boeing and Lockheed Martin that oversees NASA’s shuttle fleet. USA announced the shuttle worker layoffs in July as part of a workforce reduction plan due to the space shuttle fleet’s impending retirement.

The layoffs, which affect workers in Florida, Alabama and Texas, will take effect Friday. USA spokeswoman Kari Fluegel told SPACE.com in July that the layoffs would occur despite the addition by Congress of an extra shuttle flight to NASA’s schedule. However, the extra mission could affect plans for any future layoffs, she added.

NASA and its contractors are currently preparing the shuttle Discovery to launch Nov. 1 to deliver a new storage room and humanoid robot prototype to the station. The shuttle Endeavour is slated to fly Feb, 26, 2011 to deliver a nearly $2 billion astrophysics experiment – called the Alpha Magnetic Spectrometer – to the space station. After that flight, the $100 billion station will be complete after more than 12 years of construction.

Big new rocket

Obama’s space plan also calls for astronauts to visit an asteroid by 2025 and then aim for a manned Mars mission in the 2030s. A heavy-lift rocket for those missions was slated to begin development in 2015.

Under the spending bill approved Wednesday, NASA would be directed to begin work on that heavy-lift rocket in 2011 – four years earlier than the White House proposal.

Congressman Pete Olson (R-Texas) said such a rocket is vital for NASA to fulfill its original purpose.

“Our future in space is not in low-Earth orbit. We have to go beyond,” Olson said during the vote’s debate. “A heavy-lift vehicle will enable us to achieve the true mission of the agency … to explore.”

New NASA bill

Gordon said Wednesday that while he had a number of concerns about the Senate’s NASA bill, he believed that “a flawed bill is better than no bill at all.”

The bill should help NASA and its workforce get on with the transition from its previous Constellation program to the new deep space exploration plan set forth by President Obama, House officials said

“While the bill before us today is far from perfect, it offers clear direction for a NASA that’s floundering,” said Ralph Hall (R-Texas), the ranking member of the House Science and Technology Committee, during the bill’s discussion.

However, some House members took issue with what they called the bill’s “unfunded mandate” to continue the space shuttle program through Sept. 30, 2011. The extension would cost some $500 million and lawmakers questioned where NASA will find the extra funds.

Congresswoman Gabrielle Giffords (D-Arizona), who is married to space shuttle commander Mark Kelly, said the bill “lacks serious budgetary discipline.”

Some lawmakers expect the NASA authorization bill will preserve some jobs and create others associated with new programs.

“Without a bill, the jobs of a world class NASA workforce and thousands of highly-skilled private contractors who support human space flight would have been lost,” Hall said in a statement released after the vote.

Copyright © 2010 Space.com. All Rights Reserved. This material may not be published, broadcast, rewritten or redistributed.

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September 16, 2010

Boeing Aims to Fly Passengers to Space on New Capsule

Filed under: Cool, Gadgets, Government Policies, Military, Space Exploration, Space Ships — bferrari @ 11:35 am
Helping pave the road for the future of commercial spaceflight, Boeing is hard at work on the research and development of a new space capsule aimed at flying people to the International Space Station. (BOEING)

Helping pave the road for the future of commercial spaceflight, Boeing is hard at work on the research and development of a new space capsule aimed at flying people to the International Space Station. (BOEING)

Aerospace heavyweight Boeing has teamed up with a private spaceflight marketing firm to sell passenger seats for future flights in its new space capsule.

Under the agreement, the Virginia-based Space Adventures will market passenger seats on commercial flights aboard the Boeing Crew Space Transportation-100 spacecraft, currently being designed to travel to the International Space Station as well as other future private space stations.

The capsule seats could go to space tourists, individual companies or other non-government groups, as well as U.S. federal agencies other than NASA.

“We want to expand beyond flying astronauts just to the ISS,” said Brewster Shaw, vice president and general manager of Boeing’s Space Exploration division, in a press conference today (Sept. 15). “Very few people have made it to orbit of our species — probably a little over 500 out of 6 or 7 billion people. That’s not enough. We want to see many more have that opportunity.”

The first test flights of the new CST-100 space capsule are slated to launch by 2015, Boeing officials said. The capsule is designed to launch atop an expendable rocket.

No strangers to spaceflight

Space Adventures has successfully contracted and flown seven spaceflight participants on eight separate missions to the International Space Station. As one of the leading suppliers of human space systems and services, Boeing also has a strong heritage in the industry, company officials said. [10 Private Spaceships Becoming Real]

“By combining our talents, we can better offer safe, affordable transportation to commercial spaceflight customers,” Shaw said. “If NASA and the international partners continue to accommodate commercial spaceflight participants on ISS, this agreement will be in concert with the NASA administrator’s stated intent to promote space commerce in low-Earth orbit.”

The two companies have yet to set a price per seat on the CST-100 capsule, but did say it will be competitive with the current Russian launches on Soyuz spacecraft used by Space Adventures. The last passenger trip to the International Space Station — the October 2009 trip of Canadian billionaire Guy Laliberte — cost about $40 million, Space Adventures officials said.

“We’re not ready to talk about the price yet,” said Eric Anderson, co-founder and chairman of Space Adventures. “Certainly a lot of that comes from the launch vehicle choice, including what the destination is and what the experience is.”

Boeing’s new reusable spaceship

Boeing’s CST-100 spacecraft is approximately 15 feet (4.5 meters) wide and can carry up to seven people. The cone-shaped capsule will look similar to NASA’s Apollo and Orion spacecraft.

The company has set a design requirement that the CST-100 be reusable up to 10 times. The exact number of times the capsule is reused, however, will depend upon inspection after touchdown.

The CST-100 is part of the company’s $18 million award from NASA under the Commercial Crew Development Space Act Agreement. The award aims to advance the concepts and technology required to build a commercial crew space transportation system.

“We are excited about the potential to offer flights on Boeing’s spacecraft,” Anderson said. “With our customer experience and Boeing’s heritage in human spaceflight, our goal is not only to benefit the individuals who fly to space, but also to help make the resources of space available to the commercial sector by bringing the value from space back to Earth.”

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