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Monday, April 7, 2008

NASA goes low-tech to fix high-tech problem

WASHINGTON (AP) -- To fix a potentially fatal shaking problem on its snazzy new moon rocket, NASA is considering something that works for mud-stained pickups: heavy-duty shock absorbers.

For nearly half a year, NASA's No. 1 technical problem in designing its Ares I rocket, which will eventually propel astronauts back to the moon, has been a sound wave vibration problem from its solid rocket motors.

If the vibrations hit the right frequency, they could shake the astronauts to death -- or at the least make it impossible for them to work. The astronauts would be in the Orion crew capsule launched on top of the Ares.

The leading solution is to put weight on springs in parts of the bottom end of the rocket and underneath astronauts' seats to dampen the vibrations. Think MacPherson struts, said Garry Lyles, who heads a NASA team working on the problem.

"These are actually absorbers that are used in vehicles today, especially 1-ton and 1½-ton pickup trucks," Lyles said Thursday.

He said it's possible that further analysis and tests will reveal that the shaking problem that's turned up in computer models of the still unbuilt Ares may be a non-issue. But engineers are seeking solutions just in case.

NASA is not ready to proclaim the case closed and still considers it the highest level of potential problem, Lyles said.

Ares project manager Steve Cook called it "a very manageable issue."

There are many such challenges that face NASA's return-to-the moon program, according to a report issued Thursday by outside federal auditors.

The Government Accountability Office highlighted other potential problems, including too much weight in both the rocket and Orion capsule, design issues with a new engine for a booster, insufficient facilities for certain types of testing, and private industry's inability to make the Orion capsule's 1960s-style peel-away heat shield.

None of the technical problems is "a fatal flaw," the report's author, Christine Chaplain, told a House Science subcommittee Thursday.

Former astronaut Kathryn Thornton, associate dean of engineering at the University of Virginia, said experts believe that one of the biggest problems is that the space agency is set on a schedule of returning people to the moon by 2020 without enough money.

Getting to the moon by that date is "exceedingly unlikely," she told the subcommittee.

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The Next Giant Leap For Mankind


A Bigger Leap For Mankind


With the Space Shuttle program ending soon, NASA is planning to return men to the moon in preparation for a manned flight to Mars. Bob Simon reports. | Share/Embed



(CBS) NASA is serious, very serious, about launching the most difficult mission ever attempted by the human race - putting an astronaut on Mars. The voyage will cover hundreds of millions of miles and take two-and-a-half years roundtrip. It sounds like science fiction.

To make it scientific fact, the United States needs to first flex its deep space muscles again on familiar terrain - the moon.

It’s been nearly 40 years since Neil Armstrong took one giant leap for mankind and almost as long since the American public was truly captivated by the space program. You may not know it, but as 60 Minutes correspondent Bob Simon reports, the journey to send humans back to the moon and beyond has already begun.



From the mountains of Utah to the factory floors of Cleveland, from the space center in Houston to the marshes of Virginia, spacesuits are being tested, rockets are being fired, and capsules are being designed. The United States is once again aiming to launch astronauts to the moon and yes, even, to Mars.

"What’s impossible? What can’t we do if we wanna do it badly enough?" says Gene Cernan, the last man to walk on the moon. He calls his trip on Apollo 17 a visit to God’s front porch. He says anything seemed achievable in those days.

"When I came back from the moon in ’72, [I] stood on my soapbox and said, ‘We’re not only going back to the moon, we’re gonna be on our way to Mars by the turn of the century.' I believed it with my whole heart. But my glass has been half empty for the last 30 years. Now, it’s half full."

It’s half full because NASA is returning to what Cernan calls the romance of space: dramatic human missions to other worlds.

What will propel the astronauts is the new Ares rockets, but they won’t be ready until 2015.

Dr. Rick Gilbrech is NASA’s exploration chief.

"A lot of people don’t understand. They say, ‘Why can’t we go to the moon, we've already been there.' Well, we can’t really roll up the garage door and dust off the Saturn V rockets. That whole infrastructure was dismantled after the Apollo program."

The decision to dismantle Apollo and to cancel possible future trips to places like Mars was made during the Nixon era. Dr. Mike Griffin, NASA's current director, says that was wrong. "It has to rank as one of the colossal mistakes in history," he says.

And that mistake, Griffin says, led to the Space Shuttle, which he believes doesn’t generate as much excitement because it never leaves the Earth’s orbit. Griffin says Americans are bored by the space program because NASA has run a boring space program. The Space Shuttle will finally be retired in two years. In its place: the new exploration program called Constellation.

There is no question Mars is the ultimate goal, but why return to the moon? Why not go straight to Mars? "If we didn’t have a moon, we would. And we could. But it would be much riskier," Griffin says.

To get to Mars, the astronauts will need to travel several hundred million miles before landing. If something goes wrong along the way, the astronauts would never make it back to Earth.

Mars is a tough place to do business; Steve Squyres should know. He is the principal investigator for the Mars rovers Spirit and Opportunity. Squyres and everyone at NASA were greatly relieved when they landed safely on the red planet four years ago.

The rovers have been a huge success in exploring Mars and transmitting rare pictures from there. Prior to their landing, roughly two-thirds of all missions to the planet had failed. Squyres calls Mars a spacecraft graveyard.

"The accuracy with which you need to target a landing site on the surface is like throwing a basketball from New York to Los Angeles and having it go through without touching the rim," he explains.

If the astronauts make that shot, if they land on Mars, they will face a deadly environment - radiation from solar flares, dangerous dust and temperatures that average 60 degrees below zero. And they’ll have to do it for up to 18 months. That’s how long it will take before the Earth and Mars align properly again for a faster return home. No astronauts have ever spent that amount of time on another world. Neil Armstrong was on the moon for less than a day.

"And I think it’s more responsible for us to go to the moon, check out these systems, make sure the life-support systems, the space suits, the little things we need for these long voyages, work properly," Gilbrech explains.

The new lunar missions will be about more than putting flags in the sand. This time, NASA wants its astronauts on the moon for weeks, even months, to work out any kinks.

"And going to the moon, staying for months, wearing the space suit all the time?" Simon asks.

"No," says Gilbrech. "We have planned to have habitats so that they’ll have short-sleeve environments." He says the goal is to have towns on the moon.


To help essentially colonize the moon, NASA is trying out a new generation of rovers.

During Apollo, the furthest the astronauts could ever venture out on their lunar rovers was six miles. NASA hopes the new rovers will let the astronauts explore 60 miles from their spacecraft. Technological advancements will help in another way. Think about this: There is more computing power in your average cell phone today than there was on any of the Apollo spacecraft that took the astronauts to the moon.

Another example of how the new missions might be different is the
robonaut, which looks like a cousin of C-3PO. It’s an early model of a robot that might assist the astronauts with mundane and sometimes dangerous tasks on the moon.

The astronauts who set up towns on the moon will need to learn to adapt. At the
Glenn Research Center near Cleveland, engineers are testing a machine that simulates one-sixth gravity.

"No matter how many times you see astronauts walking on the moon, you have no idea what it feels like," says Simon while walking on the vertical treadmill, a surreal machine that simulates the feel of walking on the moon.

Without exercise in space, the astronauts could lose significant bone mass and also see their muscles atrophy.

CBS)
NASA isn’t using the moon just to train for Mars. Next year, it will launch orbiters around the moon and then essentially blast the lunar surface. In the midst of the debris field, NASA hopes to find evidence of hydrogen, which could one day help fuel trips home for the astronauts. But will there be any missions for the astronauts at all?

The biggest obstacle NASA faces is money. One critic has called the Constellation program "Apollo on food stamps." During the 1960s, 4 percent of the entire national budget was spent on space. Today one-sixth of 1 percent goes to NASA.

"The average American’s bill, if you will, for the space program, is 15 cents per person, per day," says Griffin. "I don’t know about you, but I spend more than that on bubble gum."

And there are worries there could be further cuts. Constellation is a tempting target in a difficult economy. The money squeeze is the main reason why the U.S. won’t set foot on the moon until 2020. A Mars landing won’t take place until about 2030. To defray costs for the trip to Mars, NASA may need an international partner. If it's up to Congressman Barney Frank, D-Mass., who tried to halt the Mars program, Americans won’t be part of any human missions to the planet. So what does he have against Mars?

"I don’t have anything against a lot of things I don’t wanna spend hundreds of billions of dollars on," says Rep. Frank. "Sending human beings there for the sole purpose of proving that we can do it and bringing them back requires an enormous amount of money at a time when we have a serious deficit, when we are not adequately funding a lot of very important needs right here at home."

Others wonder why NASA doesn’t simply continue to send rovers like Spirit and Opportunity to Mars. Miraculously, they not only survived the landing, they have survived for four years on the Martian surface. The rovers were originally supposed to last only three months. The rovers are cheaper and don’t put humans at risk. But what rovers can do in a day, humans could do in a minute. And manned missions to Mars could intensify a very important search, according to Squyres, the lead scientist for the rovers.

"We’re exploring Mars, fundamentally, because it may once have harbored life," he says. "So, by going to Mars we can address basic questions like, 'How did life first come to be? Is life common or rare throughout the universe?' These are big questions."

Discoveries by the rovers have given hints to the possibilities of life on Mars. Perfect, blueberry-like spheres on the surface are made of a mineral that is often formed in water on Earth. Last year, white dirt appeared in Spirit’s tracks. It was silica. The presence of water is required to produce such a high concentration. And inside what’s known as the Victoria Crater, Opportunity is finding proof that water once saturated the sub-surface of Mars. Water is the essential ingredient for life. Which brings up an if?

"This is a big if," Squyres says, "but if you could show that life arose independently on two different planets just in this one solar system, when you consider the multitudes of solar systems that there are out there, it takes no great leap of logic or faith or anything else to believe that life might actually be commonplace throughout the universe."

And if that isn’t enough to think about, the real issue may not be whether there was or is life on Mars, but whether there will be life on Mars.

Griffin says "I think Mars will figure prominently in the future of the human race. Well, I think Mars is in, in the distant future, is another home for human beings."

Human settlements on Mars: is it all just a dream? Will the American public even support traveling to places humans can barely imagine? That may be the biggest question of all.

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Solar System's 'look-alike' found


Almost 300 planets have now been found outside our Solar System

Astronomers have discovered a planetary system orbiting a distant star which looks much like our own.

They found two planets that were close matches for Jupiter and Saturn orbiting a star about half the size of our Sun.

Martin Dominik, from St Andrews University in the UK, said the finding suggested systems like our own could be much more common than we thought.

And he told a major meeting that astronomers were on the brink of finding many more of them.

The St Andrews researcher said this planetary system, and others like it, could host terrestrial planets like Earth. It was just a matter of time before such worlds were detected, he explained.

Dr Dominik told BBC News: "We found a system with two planets that take the roles of Jupiter and Saturn in our Solar System. These two planets have a similar mass ratio and similar orbital radius and a similar orbital period.

"It looks like this may have formed in a similar way to our Solar System. And if this is the case, it looks like [our] Solar System cannot be unique in the Universe. There should be other similar systems out there which could host terrestrial planets."

Dr Dominik presented his work at the Royal Astronomical Society's National Astronomy Meeting in Belfast.

Ultimate goal

The newfound planetary system, which orbits the star OGLE-2006-BLG-109L, is more compact than our own and is about five thousand light-years away.

Although nearly 300 extrasolar planets have been identified, astronomers have consistently failed to find planetary systems which resemble our own. Dr Dominik said only 10% of systems discovered so far are known to host more than one planet.

But he explained that all the techniques currently used to find exoplanets were strongly biased towards detecting gas giant planets orbiting at short distances from their parent stars.

The OGLE planets were found using a technique called gravitational micro-lensing, in which light from the faraway planets is bent and magnified by the gravity of a foreground object, in this case a another star.

"It's a kind of scaled-down version of our Solar System. The star the planets are orbiting is half as massive as the Sun and they orbit half as distant to their host star as Jupiter and Saturn orbit around the Sun," said Dr Dominik.

He said that the ultimate goal for exoplanet researchers was to find habitable Earth-like and Mars-like planets. This aim was achievable, he said, because technology was improving all the time.

"I think it will happen quite soon," he said, adding: "Micro-lensing can already go below Earth mass and it has detected more massive planets in the habitable zone. So in the next few years, we will see something really exciting."

Dr Dominik said there was competition between teams of astronomers using micro-lensing and those who favoured the transit technique, which seeks to detect new planets when, from our point of view, they pass directly in front of the parent star they are orbiting. The planet blocks a tiny fraction of the star's light, causing the star to periodically dim.

But he added that there was little chance to detect Earth-like worlds in OGLE-2006-BLG-109L because the system was too distant for current techniques to resolve planets the size of our own.

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