U.S. warns of space “dodgeball” after satellite crash

 

Iridium says in dark before orbital crash

By Jim Wolf Jim Wolf 2 mins ago

WASHINGTON (Reuters) – Iridium Satellite LLC said Thursday it had no advance warning of an impending collision between one of its communications satellites and a defunct Russian military satellite above Siberia.

Amid questions of liability, negligence and possible lawsuits, the closely held company rejected suggestions that it might have come to disregard “conjunction reports” — potential accident alerts — routinely relayed by the U.S. military.

“Iridium didn’t have information prior to the collision to know that the collision would occur,” said Liz DeCastro, a company spokeswoman. “If the organizations that monitor space had that information available, we are confident they would have shared it with us.”

She was responding to questions about an 18-month-old presentation by retired U.S. Air Force General John Campbell, Iridium’s executive vice president for government programs.

Iridium had been receiving a weekly average of 400 conjunction reports from the U.S. Strategic Command‘s Joint Space Operations Center that tracks debris in space, Campbell told a June 2007 forum hosted by the George C. Marshall Institute, a Washington research group.

“So the ability actually to do anything with all the information is pretty limited,” he said, describing a kind of data overload. The conjunction reports were issued every time a potential threat object was to pass within five kilometers (3 miles) of a commercial satellite, he said.

“Even if we had a report of an impending direct collision, the error would be such that we might maneuver into a collision as well as move away from one,” he told the panel.

Campbell then endorsed the so-called “Big Sky” theory — that space is so vast that the chances of a collision are infinitesimal, despite more than 18,000 pieces of orbiting junk big enough to track.

“We figure that the risk of a collision on any individual conjunction is about 1 in 50 million,” he said at the time, adding: “Clearly that risk is something bigger than zero.”

‘DODGEBALL’ TO AVOID DEBRIS

Marine Corps General James Cartwright, vice chairman of the Joint Chiefs of Staff and a former head of the command that runs U.S. military space operations, said countries with satellites in space will have to play “dodgeball” for decades to avoid debris from the collision. It occurred about 485 miles

above the Russian Arctic on Tuesday.

James Lewis, a former official at the State and Commerce departments now at the Center for Strategic and International Studies, raised a question at the same forum about whether Iridium might have a case against the Russians.

“There was negligence somewhere,” he said. Asked about this at the forum, Cartwright declined to discuss it but said he would like to see more information-sharing on debris avoidance with Russia, China, France and other countries using space.

The mishap marked the first time two intact spacecraft accidentally ran into each other, Nicholas Johnson, chief scientist of NASA‘s Orbital Debris Program Office at the Johnson Space Center in Houston, told Space.com.

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

Cartwright, who from 2004 to 2007 headed the Pentagon‘s Strategic Command responsible for space operations, said the military had been alerted by Iridium to the sudden “non-reporting” of the destroyed craft.

Iridium runs a network that uses 66 satellites to provide voice and data services for areas not served by ground-based communications networks. The network has about 300,000 clients.

Bryan Whitman, a Pentagon spokesman, said it was not possible for the U.S. military to track and predict the movements of all 18,000 objects in space all the time.

“Because there is so much, you have to prioritize what you’re looking at,” he said. “There are limits on your ability to track and compute every piece…”

“We did not predict this collision,” he said.

China added significantly to space debris when it used a ground-based ballistic missile to blow apart an obsolete weather satellite in a January 2007 arms test. The United States used a missile from a Navy warship to explode a tank of toxic fuel on a crippled U.S. spy satellite last February.

China’s anti-satellite test “alone increased our risk due to space junk by a factor of about three and increased the overall risk of collision by about 15 percent,” Campbell told the forum in 2007.

(Additional reporting by Andrew Gray; editing by David Storey)

Original Article and Photos

U.S. and Russian satellites collide

February 11, 2009 3:47 PM PST

by Bill Harwood

In a commercial Iridium communications satellite and a defunct Russian satellite ran into each other Tuesday above northern Siberia, creating a cloud of wreckage, officials said today. The international space station does not appear to be threatened by the debris, they said, but it’s not yet clear whether it poses a risk to any other military or civilian satellites.

“They collided at an altitude of 790 kilometers (491 miles) over northern Siberia Tuesday about noon Washington time,” said Nicholas Johnson, NASA’s chief scientist for orbital debris at the Johnson Space Center in Houston. “The U.S. space surveillance network detected a large number of debris from both objects.”

A rendering of an Iridium satellite near earth.

(Credit: Iridium Satellite)

Air Force Brig. Gen. Michael Carey, deputy director of global operations with U.S. Strategic Command, the agency responsible for space surveillance, said initial radar tracking detected some 600 pieces of debris. He identified the Russian spacecraft as Cosmos 2251, a communications relay station launched in June 1993, and said the satellite is believed to have been non-operational for the past 10 years or so.

“As of about 12 hours ago, I think the head count was up (to around) 600 pieces,” Carey told CBS News late today. “It’s going to take about two days before we get a solid picture of what the debris fields look like. But you, I think, can imply that the majority of that should be probably along the same line as the original orbits.”

He said U.S. STRATCOM routinely tracks about 18,000 objects in space, including satellites and debris, that are 3.9 inches across or larger. Tracking priority and “conjunction analysis”–identifying which objects may pose a threat to manned spacecraft–is the first priority.

“It’s going to take a while” to get an accurate count of the debris fragments, Johnson said. “It’s very, very difficult to discriminate all those objects when they’re really close together. And so, over the next couple of days, we’ll have a much better understanding.”

Asked which satellite was at fault, Johnson said “they ran into each other. Nothing has the right of way up there. We don’t have an air traffic controller in space. There is no universal way of knowing what’s coming in your direction.”

Iridium Satellite operates a constellation of some 66 satellites, along with orbital spares, to support satellite telephone operations around the world. The spacecrafts, which weigh about 1,485 pounds when fully fueled, are in orbits tilted 86.4 degrees to the equator at an altitude of about 485 miles. Ninety-five Iridium satellites were launched between 1997 and 2002 and several have failed over the years.

“Yesterday, Iridium Satellite LLC lost an operational satellite,” the company said in a statement. “According to information shared with the company by various U.S. government organizations that monitor satellites and other space objects (such as debris), it appears that the satellite loss is the result of a collision with a non-operational Russian satellite.

“Although this event has minimal impact on Iridium’s service, the company is taking immediate action to address the loss. The Iridium constellation is healthy, and this event is not the result of a failure on the part of Iridium or its technology. While this is an extremely unusual, very low-probability event, the Iridium constellation is uniquely designed to withstand such an event, and the company is taking the necessary steps to replace the lost satellite with one of its in-orbit spare satellites.”

Johnson said the collision was unprecedented.

“Nothing to this extent (has happened before),” he said. “We’ve had three other accidental collisions between what we call catalog objects, but they were all much smaller than this and always a moderate sized objects and a very small object. And these are two relatively big objects. So this is a first, unfortunately.”

As for the threat posed by the debris, Johnson said NASA carried out an immediate analysis to determine whether the space station faced any increased risk. The station, carrying three crew members, circles the globe at an altitude of about 220 miles in an orbit tilted 51.6 degrees to the equator.

“There are two issues: the immediate threat and a longer-term threat,” he said. “It turns out, when you have a collision like this the debris is thrown very energetically both to higher orbits and to lower orbits. So there are actually debris from this event which we believe are going through the space station’s altitude already. Most of it is not, most of it is still clustered up where the event took place. But a small number are going through station’s altitude.

“Yesterday, we did an assessment of what the risk might be to station and we found it’s going to be very, very small. As time goes on, (that) debris will (come down) some over months, most over years and decades and as the big ones come down they’ll be tracked, we’ll see them and the worst-case scenario, we’ll just dodge them if we have to. It’s the small things you can’t see are the ones that can do you harm.”

Asked if other satellites might be at risk, Johnson said, “Technically, yes. What we’re doing now is trying to quantify that risk. That’s a work in progress. It’s only been 24 hours. We put first things first, which is station and preparing for the next shuttle mission.”

Most, if not all, of the debris is expected to eventually burn up in Earth’s atmosphere.

Bill Harwood is a space analyst for CBS News.

Original Article

2 big satellites collide 500 miles over Siberia

 

Wed Feb 11, 6:59 pm ET

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 is 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.

Nicholas Johnson, an orbital debris expert at the Houston space center, said the risk of damage from Tuesday’s collision is greater for the Hubble Space Telescope and Earth-observing satellites, which are in higher orbit and nearer the debris field.

At the beginning of this year there were roughly 17,000 pieces of manmade debris orbiting Earth, Johnson said. 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.___AP science writer Seth Borenstein in Washington and AP technology writer Peter Svensson in New York contributed to this report.___On the Net:NASA: http://www.nasa.gov

Link to Original Article