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Shuttle Endeavour and a crew of seven blasted into orbit Tuesday on what was to be the longest space station mission ever, a 16-day voyage to build a gangly robot and add a new room that will serve as a closet for a future lab.
The space shuttle roared from its seaside pad in Florida at 2:28 a.m., lighting up the sky for kilometers around as it took off on a multinational flight involving Canada and Japan.
It was a rare treat: The last time NASA launched a shuttle at nighttime was in 2006. Only about a quarter of shuttle flights have begun in darkness.
The shuttle took flight with a flash of light, giving a peach-yellow glow to the low clouds just offshore before disappearing into the darkness.
The Endeavour’s commander Dominic Gorie and his crew face a daunting job once they reach the international space station late Wednesday night. The astronauts will perform five spacewalks, the most ever planned during a shuttle visit.
The launching site was jammed with Canadians and Japanese representing two of the major partners in the international space station. The Canadian Space Agency supplied Dextre, the two-armed robot that was hitching a ride aboard Endeavour, while the Japanese Space Agency sent up the first part of its massive Kibo lab, a storage compartment for experiments, tools and spare parts.
The main part of the Kibo lab will fly on the next shuttle mission in May, with the final installment, a porch for outdoor experiments, going up next year.
Altogether, the Japanese Space Agency has invested about $6.7 billion in the space station program, including a Kibo control center near Tokyo.
Canada’s $200 million-plus Dextre, meanwhile, is designed to eventually take over some of the more routine outdoor maintenance chores from spacewalking astronauts. Dextre, short for dexterous and pronounced like Dexter, will join the space station’s Canadian-built robot arm, already in orbit for seven years.(AP)

Dextre is an essential tool for maintaining and servicing the space station. With its dual-arm design providing added flexibility, Dextre will remove and replace smaller components on the Station’s exterior, where precise handling is required. It will be equipped with lights, video equipment, a tool platform and four tool holders.

Dextre can perform dexterous tasks by sensing various forces and moments on the payload. In response, it can automatically compensate its movements to ensure the payload is manipulated smoothly.

With its two arms, Dextre will load and unload objects, use robotic tools, attach and detach covers and install various units of the Space Station. It will either be attached to the end of Canadarm2 or ride independently on the Mobile Base System and have Canadarm2 deliver equipment to it for servicing. It also has four cameras that will provide the crew inside the Station with additional views of the work areas.

Like Canadarm2 and the Mobile Base System (MBS), the Special Purpose Dexterous Manipulator will be controlled by the crew inside the International Space Station. This system will allow the crew to perform many of the tasks that would otherwise require an astronaut to perform during a demanding spacewalk.

Dextre is a sophisticated dual armed robot, which is part of Canada’s contribution to the International Space Station (ISS). Along with Canadarm2, whose technical name is the Space Station Remote Manipulator System, and a moveable work platform called the Mobile Base System, these three elements form a robotic system called the Mobile Servicing System (MSS). The three components have been designed to work together or independently.

MD Robotics, located in Brampton, Ontario, is the main contractor of the Dextre. The technology behind Dextre is built upon the heritage of its predecessor, Canadarm2. Conceptually the two robots are similar and they both operate with the support of computers; however, their design and purpose are different.

Dextre is a complex robot designed to perform intricate maintenance and servicing tasks on the outside of the ISS. Dextre will carry out delicate work that, so far, could only be accomplished by astronauts during spacewalk activities. In other words, Dextre will provide an alternative to astronauts, considerably reducing the amount of time that they have to venture out of the ISS to perform demanding spacewalks and providing more time for them to perform science on the ISS.

Upon close inspection of Dextre, one notes its resemblance to the human shape: an upper body that can pivot at the waist with shoulders that support two identical arms. Each arm has a total of seven joints, providing an incredible amount of freedom when performing a task. However, Dextre is designed so that only one arm can move at a time in order to avoid self-collision, achieve greater stability and maintain operational similarity with Canadarm2. The greater stability is provided by the immobile arm, which is first commanded to anchor Dextre to an ISS stabilization point. At the tip of each arm, we find a “hand”, known technically as the Orbital Replacement Unit/Tool Changeout Mechanism (OTCM). The OTCM consists of a set of parallel retractable jaws, which serve to grip payloads and tools. Each OTCM is also equipped with a retractable motorized socket wrench to mate and demate mechanisms on-orbit, as well as lights and a black & white camera. Dextre lower body is equipped with a pair of pan/tilt colour cameras that allow astronauts aboard the ISS, and engineers on the ground, to monitor the task, which is out of direct eyesight.

A variety of tasks will be performed by Dextre including installation and removal of small payloads such as batteries, power supplies and computers; providing power and data connectivity to payloads; and manipulating, installing, removing and inspecting scientific payloads. A typical task for Dextre is to replace a depleted (100 kg) battery, which involves bolting and unbolting operations as well as millimetre level positioning accuracy to properly align and insert the spare battery within its worksite and properly engage all connectors. This peg-in-the-hole type of task demands a great amount of precision and a gentle touch to avoid binding. To achieve this Dextre has a unique feature which complements its remarkable dexterity: precise sensing of forces and torques at the “hand” and automatic compensation to ensure the payload moves smoothly into its mounting fixture. To illustrate the level of performance of Dextre, here on Earth it could likely be used to insert an item as delicate as a videotape into a video recorder.

Dextre is a very versatile robotic tool. It can work solo, fixed to one of the base points (known as power data grapple fixtures) along the side of the Station or on the Mobile Base System. However, most of the time Dextre will do its work while attached to the free end of Canadarm2 which will manoeuvre Dextre into position next to the payload which requires maintenance along the main truss of the ISS. Astronauts aboard the ISS will operate all of the MSS components from a robotic workstation. As part of mission preparation, astronauts must undergo rigorous training to learn how to operate each component of the MSS. Canadian Space Agency engineers provide this training at the John H. Chapman Space Centre in Longueuil, Quebec.

Dextre is currently going through final testing prior to its launch slated for March 11, 2008.

The Associated Press

Space scientists and government officials are tracking two massive objects that are hurtling toward Earth, but only one, a dead satellite the size of a bus, is expected to hit somewhere on the globe.

Government officials said Saturday that a large U.S. spy satellite has lost power and could hit Earth in late February or early March. And an asteroid at least 500 feet long will make a rare close pass by Earth early Tuesday, but scientists say there is no chance of an impact.

The satellite, which no longer can be controlled, could contain hazardous materials, and it is unknown where it might come down, said the government officials, who spoke on condition of anonymity because the information is classified as secret.

“Appropriate government agencies are monitoring the situation,” says Gordon Johndroe, a spokesman for the National Security Council.

John Pike, director of the defense research group GlobalSecurity.org, estimates that the spacecraft weighs about 20,000 pounds and is the size of a small bus. Satellites have natural decay periods, and it’s possible this one died as long as a year ago and is just now getting ready to re-enter the atmosphere.

Jeffrey Richelson, a senior fellow at the National Security Archive, says the spacecraft probably is a photo-reconnaissance satellite. Those are used to gather information from space about adversarial governments and terror groups and to survey damage from hurricanes, fires and other disasters.

The closest approach of the asteroid, known as 2007 TU24, is expected to be at 334,000 miles, or about 1½ times the distance of Earth to the moon.

The nighttime encounter should be bright enough for medium-size telescopes to get a glimpse, says Don Yeomans, manager of the Near-Earth Object Program Office at NASA’s Jet Propulsion Laboratory, which tracks potentially dangerous space rocks. The closest approach is expected to be at 3:33 a.m. ET.

The asteroid TU24 is one of an estimated 7,000 so-called near-Earth objects.

An actual collision of a similar-size object with Earth occurs on average every 37,000 years.

Spotted in October by the NASA-funded Catalina Sky Survey in Arizona, TU24 is estimated to be 500 to 2,000 feet long.

The next time an asteroid this size will fly this close to Earth will be in 2027.

Contributing: Reuters

WASHINGTON (AP) — A large U.S. spy satellite has lost power and propulsion and could hit the Earth in late February or March, government officials said Saturday.

The satellite, which no longer can be controlled, could contain hazardous materials, and it is unknown where on the planet it might come down, they said.

The officials spoke on condition of anonymity because the information is classified as secret.

“Appropriate government agencies are monitoring the situation,” said Gordon Johndroe, a spokesman for the National S ecurity Council.

“Numerous satellites over the years have come out of orbit and fallen harmlessly. We are looking at potential options to mitigate any possible damage this satellite may cause.”

He would not comment on whether it is possible for the satellite to be perhaps shot down by a missile. He said it would be inappropriate to discuss any specifics at this time.

A senior government official said that lawmakers and other nations are being kept apprised of the situation.

The largest uncontrolled re-entry by a NASA spacecraft was Skylab, the 78-ton abandoned space station that fell from orbit in 1979. Its debris dropped harmlessly into the Indian Ocean and across a remote section of western Australia.

In 2000, NASA engineers successfully directed a safe de-orbit of the 17-ton Compton Gamma Ray Observatory, using rockets aboard the satellite to bring it down in a remote part of the Pacific Ocean.

In 2002, officials believe debris from a 7,000-pound science satellite smacked into the Earth’s atmosphere and rained down over the Persian Gulf, a few thousand miles from where they first predicted it would plummet.

Source: CNN

It turns out that astronomers have recently discovered what is believed to be a dark galaxy; a starless mass of spinning matter located some 50 million light-years away in the Virgo cluster of galaxies.

A newly discovered hunk of space rock has a 1 in 75 chance of slamming into the red planet on January 30, scientists said Thursday.

“These odds are extremely unusual. We frequently work with really long odds when we track … threatening asteroids,” said Steve Chesley, an astronomer with the Near Earth Object Program at NASA’s Jet Propulsion Laboratory.

The asteroid, known as 2007 WD5, was discovered in late November and is similar in size to an object that hit remote central Siberia in 1908, unleashing energy equivalent to a 15-megaton nuclear bomb and wiping out 60 million trees.