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Big Communication Satellites Crash 500 Miles Above Siberia
Wednesday, February 11, 2009
CAPE CANAVERAL, Fla. Two big communications satellites collided in the first-ever crash of two intact spacecraft in orbit, shooting out a pair of massive debris clouds and posing a slight risk to the international space station.

NASA said it will take weeks to determine the full magnitude of the crash, which occurred nearly 500 miles over Siberia on Tuesday.

"We knew this was going to happen eventually," said Mark Matney, an orbital debris scientist at Johnson Space Center in Houston.

NASA believes any risk to the space station and its three astronauts should be low. It orbits about 270 miles below the collision course. There also should be no danger to the space shuttle set to launch with seven astronauts on Feb. 22, officials said, but that will be re-evaluated in the coming days.

The collision involved an Iridium commercial satellite, which was launched in 1997, and a Russian satellite launched in 1993 and believed to be nonfunctioning. The Russian satellite was out of control, Matney said.

The Iridium craft weighed 1,235 pounds, and the Russian craft nearly a ton.

No one has any idea yet how many pieces were generated or how big they might be.

"Right now, they're definitely counting dozens," Matney said. "I would suspect that they'll be counting hundreds when the counting is done."

As for pieces the size of micrometers, the count will likely be in the thousands, he added.

There have been four other cases in which space objects have collided accidentally in orbit, NASA said. But those were considered minor and involved parts of spent rockets or small satellites.

As of Wednesday, there were 9,831 pieces of manmade debris not counting anything from Tuesday's collision orbiting Earth. The items, at least 4 inches in size, are being tracked by the U.S. Space Surveillance Network, which is operated by the military. The network detected the two debris clouds created Tuesday.

Litter in orbit has increased in recent years, in part because of the deliberate breakups of old satellites. It's gotten so bad that orbital debris is now the biggest threat to a space shuttle in flight, surpassing the dangers of liftoff and return to Earth. NASA is in regular touch with the Space Surveillance Network, to keep the space station a safe distance from any encroaching objects, and shuttles, too, when they're flying.

"The collisions are going to be becoming more and more important in the coming decades," Matney said.

Iridium Holdings LLC has a system of 65 active satellites which relay calls from portable phones that are about twice the size of a regular mobile phone. It has more than 300,000 subscribers. The U.S. Department of Defense is one of its largest customers.

The company has spare satellites, and it is unclear whether the collision caused an outage. An Iridium spokeswoman had no immediate comment.

Initially launched by Motorola Inc. in the 1990s, Iridium plunged into bankruptcy in 1999. Private investors relaunched service in 2001.

Iridium satellites are unusual because their orbit is so low and they move so fast. Most communications satellites are in much higher orbits and don't move relative to each other, which means collisions are rare.

Iridium Holdings LLC, is owned by New York-based investment firm Greenhill & Co. through a subsidiary, GHL Acquisition Corp., which is listed on the American Stock Exchange. The shares closed Wednesday down 3 cents at $9.28.

rosco 357

i read about this , or skimmed it somewhere, i think but not sure, that it said it may effect the hubble space telescope. or maybe even endanger it, but i may be wrong, and its the space station, or its both,, take care


U.S. and Russia track satellite crash debris
Thu Feb 12, 2009 11:53am EST By Guy Faulconbridge

MOSCOW (Reuters) - Space officials in Russia and the United States were on Thursday tracking hundreds of pieces of debris that were spewed into space when a U.S. satellite collided with a defunct Russian military satellite.

The crash, which Russian officials said took place on Tuesday at about 1700 GMT (12:00 p.m. EST) above northern Siberia, is the first publicly known satellite collision and has raised concerns about the safety of the manned International Space Station.

The collision happened in an orbit heavily used by satellites and other spacecraft and the U.S. Strategic Command, the arm of the Pentagon that handles space, said countries might have to maneuver their craft to avoid the debris.

"The collision of these two space apparatuses happened by chance and these two apparatuses have been destroyed," Major-General Alexander Yakushin, first deputy commander of Russia's Space Forces, told Reuters.

"The fragments pose no danger whatsoever to Russian space objects," he said. When asked if the debris posed a danger to other nations' space craft, he said: "As for foreign ones, it is not for me say as it is not in my competency."

The collision between the Iridium Satellite LLC-operated satellite and the Russian Cosmos-2251 military satellite occurred at about 485 miles above the Russian Arctic.

That is an altitude used by satellites that monitor weather, relay communications and perform scientific observations.

"It's a very important orbit for a lot of satellites," said Air Force Colonel Les Kodlick from the U.S. Strategic Command. "We believe it's the first time that two satellites have collided in orbit."

The U.S. Joint Space Operations Center was tracking 500 to 600 new pieces of debris, some as small as 4 inches across, in addition to the 18,000 or so other man-made objects it previously catalogued in space, he said.

Russian Space Forces said it was monitoring debris that was spread over altitudes between 500 km (310 miles) and 1300 km (807 miles) above earth.

The priority is guarding the International Space Station, which orbits at 220 miles, substantially below the collision altitude. One Russian and two U.S. astronauts are currently aboard the station.


The orbit of the ISS can be changed by controllers from Earth but even a tiny piece of debris can cause significant damage to the space station as it travels at 8 km per second.

"If there is any threat to the ISS then there will be an announcement," one Russian space official said. Another said there was little immediate threat to the station.

The crash has underlined concerns about how crowded the orbit paths around the planet have become in recent decades.

But experts said the chances of such a collision are extremely low and added that leading space powers have been racing to develop new ways to destroy orbiting objects.

"The orbital altitude where the collision took place is among the most crowded in low Earth orbit," Texas-based security consultancy Stratfor said in a research note.

"But statistically speaking, the enormous scale of space makes the chance that this kind of direct collision would occur completely by accident infinitesimal," it said.

The collision occurred in a polar orbit not far from that of a defunct Chinese weather satellite shot apart by a ground-based ballistic missile in a Chinese weapons test in January 2007.

The United States used a missile to blow apart a tank of toxic fuel on a defective U.S. spy satellite last February.

There was no indication that Tuesday's collision was intentional on the part of anyone, said a U.S. government source who asked not to be named.

The European Union said on Thursday leading nations should adopt a code of conduct for civil and military activities in space.


A one pound object travelling at 17,500 mph, has a kinetic energy of 10 1/4 milliom foot pounds. That would be the same as getting hit by a 100,000# locomotive at 70 miles an hour.

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