Kamis, 11 September 2008

New moon rocket passes NASA review

NASA's new moon rocket passed a key design milestone late Wednesday: Senior NASA management unanimously approved the preliminary design review of the planned Ares I rocket that would launch astronauts into space by 2015 and back to the moon by 2020.

But next year there will be another narrowly focused "delta" preliminary design review for one pending engineering issue — too much shaking after launch.

This is the first preliminary design review approval for a rocket that carries astronauts since 1973, when the space shuttle passed the same stage, said Steve Cook, NASA's Ares projects manager.

These reviews are to make sure that the broad design, plans and software mesh properly and pass early safety questions. A more detailed test — a critical design review — is scheduled for March 2011.

Most of the rocket is not built yet.

"This is where we wrap the entire vehicle together to say we have a sound design from stem to stern," Cook said in a Wednesday evening teleconference. "It's really a big step in our journey to launch."

NASA engineers last month said they had figured out how to fix the remaining shaking issue with giant shock absorbers, but still more work is needed before that can pass review.

About 10 per cent of the problems that engineers brought up are still to be resolved but do not require a separate review, including noise problems and questions if the rocket could fly through rough weather, especially lightning, Cook said. NASA is also looking at potential problems that could come when the lower part of the rocket separates.

The Orion crew capsule, which will sit on top of the Ares I, will have its preliminary design review in late 2009.

One issue raised was that engineers would have to make sure they shrunk the launch platform design by 20 cm to match an equivalent reduction in the size of the the bottom part of the rocket.

It's mostly a matter of paperwork, Cook said.

NASA is spending about $3 billion US a year on the return-to-the moon program.

source

Selasa, 09 September 2008

Scientists hope for surprises in Big Bang experiment

Scientists involved in a historic "Big Bang" experiment to begin this week hope it will turn up many surprises about the universe and its origins -- but reject suggestions it will bring the end of the world.

And Robert Aymar, the French physicist who heads the CERN research centre, predicted that discoveries to emerge from his organization's 6.4 billion euro ($9.2 billion) project would spark major advances for human society.

"If some of what we expect to find does not turn up, and things we did not foresee do, that will be even more stimulating because it means that we understand less than we thought about nature," said British physicist Brian Cox.

"What I would like to see is the unexpected," said Gerardus t'Hooft of the University of Michigan. Perhaps, he suggested, the Large Hadron Collider (LHC) machine at the heart of the experiment "will show us things we didn't know existed."

Once it starts up on Wednesday, scientists plan to smash particle beams together at close to the speed of light inside CERN's tightly-sealed Large Hadron Collider to create multiple mini-versions of the primeval Big Bang.

Cosmologists say that that explosion of an object the size of a small coin occurred about 13.7 billion years ago and led to formation of stars, planets -- and eventually to life on earth.

A key aim of the CERN experiment is to find the "Higgs boson," named after Scottish physicist Peter Higgs who in 1964 pointed to such a particle as the force that gave mass to matter and made the universe possible.

But other mysteries of physics and cosmology -- supersymmetry, dark matter and dark energy among them -- are at the focus of experiments in the 27-km (17-mile) circular tunnel deep underneath the Swiss-French border

FEARS OF DISASTER

CERN, the European Centre for Nuclear Research, says its key researchers -- and many ordinary staff -- have been inundated by e-mails voicing fears about the experiment.

There have been claims that it will create "black holes" of intensive gravity sucking in CERN, Europe and perhaps the whole planet, or that it will open the way for beings from another universe to invade through a "worm hole" in space-time.

But a safety review by scientists at CERN and in the United States and Russia, issued at the weekend, rejected the prospect of such outcomes.

"The LHC will enable us to study in detail what nature is doing all around us," Aymar, who has led CERN for five years, said in response to that review. "The LHC is safe, and any suggestion that it might present a risk is pure fiction."

Cox, from the School of Physics and Astronomy at Britain's Manchester University, was even more trenchant. "I am immensely irritated by the conspiracy theorists who spread this nonsense around," he said.

When the experiment begins soon after 9 a.m. (0700 GMT) on September 10, disaster scenarists will have little to work on.

In the first tests, a particle beam will be shot all the way around the LHC channel in just one direction. If all goes well, collisions might be tried within the coming weeks, but at low intensity. Any bangs at this stage, said one CERN researcher, "will be little ones."

source

Google Earth Gets Highest-Res Satellite Images Ever

Google Earth will be receiving the highest resolution color satellite images available on the commercial market, thanks to Saturday's successful launch of the GeoEye-1 satellite from Vandenberg Air Force Base in California.

The GeoEye-1 satellite will capture digital images of Earth from a distance of 423 miles, while moving at 4.5 miles per second.

The GeoEye-1 satellite is able to capture images at 5.5 feet resolution in color and 16 inches resolution in black and white. However, under current government regulations, GeoEye can only offer 1.64 feet resolution images to the general public.

Google founders Larry Page and Sergey Brin were on hand to watch the launch of GeoEye-1, according to Google spokesman Brian O'Shaughnessy, Reuters reported.

Reuters said that while GeoEye does provide images to Google competitors such as Yahoo!, that Google will be GeoEye's only online-search mapping customer.

The GeoEye-1 satellite was constructed by solution provider General Dynamics Advanced Information Systems, at General Dynamics' Gilbert, Ariz., facility. General Dynamics (No. 9 on the 2008 VARBusiness 500) designed and manufactured the satellite, integrated the camera and optical telescope assembly, and did environmental testing of the satellite.

The steadiness of the camera, the agility of the satellite, and the ability to map large areas daily are all innovations we've incorporated into the GeoEye-1 satellite, said Mike Greenwood, a General Dynamics spokesman.

Matthew O'Connell, GeoEye chief executive officer, said in a statement, "Later this fall, we will start providing high-resolution color imagery of the Earth from our newest satellite to customers around the globe. The imagery from GeoEye-1 adds to the quantity and quality of that currently provided by our IKONOS satellite, and together this magnificent constellation will enable us to meet world-wide customer demand."

source