Space Station Computer Glitch May Require Spacewalk Fix, Delay Cargo Ship Launch

[Buster's Uncle]

Space Station Computer Glitch May Require Spacewalk Fix, Delay Cargo Ship Launch
SPACE.com
by Tariq Malik, Managing Editor  12 hours ago



This image from a NASA space shuttle mission shows the International Space Station in orbit. The space station is the size of a football field and home to six astronauts. Image taken: Feb. 10, 2010.



NASA is studying a glitch with a backup computer on the International Space Station, an issue that could potentially force astronauts to perform a spacewalk repair and delay the planned Monday launch of a SpaceX cargo ship.

Space station officials announced the glitch late Friday (April 11) after confirming that a backup computer on the space station's exterior was not responding to commands. The computer, known in NASA parlance as a Multiplexer-Demultiplexer, is a backup controller for some robotics systems on the space station.

"The computer outage does not pose a risk to the six crew members aboard the space station," NASA officials wrote in a statement. "ISS [International Space Station] teams are assessing next steps to attempt to bring the computer back online or replace it."

Any plan to replace the backup computer would require a spacewalk by astronauts, NASA officials added. Meanwhile, the primary computer in the affected system is working normally.

The glitch comes three days ahead of the planned launch of a Dragon cargo ship by the private spaceflight company SpaceX on Monday (April 14). The Dragon spacecraft is due to launch from Cape Canaveral Air Force Station in Florida atop a Falcon 9 rocket. It is packed with nearly 5,000 lbs. (2,268 kilograms) of supplies for the station's crew, but can only be captured by the space station's robotic arm.

"The backup [computer] would provide redundancy for robotic systems that will be needed to attach the SpaceX Dragon spacecraft currently scheduled to launch on Monday and rendezvous with the ISS on Wednesday," NASA officials wrote in a statement. "NASA is continuing to work toward a Monday launch.

SpaceX's Dragon launch has already been delayed nearly a month due to unrelated damage to a ground-based tracking radar system used by the Florida launch site that has since been repaired.

SpaceX has a $1.6 billion contract with NASA to provide 12 unmanned cargo delivery missions to the International Space Station using its Dragon spacecraft and Falcon 9 rockets. Monday's planned launch will be the SpaceX's third Dragon delivery mission for NASA since 2012.

Another company, the Dulles, Va.-based Orbital Sciences Corp., has a $1.9 billion contract with NASA for eight cargo missions using its own unmanned Antares rockets and Cygnus spacecraft. The first official Cygnus cargo mission launched in January, with the next one slated for June.


http://news.yahoo.com/space-station-computer-glitch-may-require-spacewalk-fix-113555669.html

[Buster's Uncle]

Space station computer outage may force spacewalk
Associated Press
By MARCIA DUNN  16 hours ago



FILE - This May 23, 2011 photo released by NASA shows the International Space Station at an altitude of approximately 220 miles above the Earth, taken by Expedition 27 crew member Paolo Nespoli from the Soyuz TMA-20 following its undocking. A computer outage at the International Space Station may require a spacewalk by astronauts and threatens to delay next week's launch of a commercial supply ship for NASA. NASA said Friday night April 11, 2014 that a backup computer on the outside of the orbiting lab is not responding to commands. (AP Photo/NASA, Paolo Nespoli)



CAPE CANAVERAL, Fla. (AP) — A computer outage at the International Space Station may require a spacewalk by astronauts and threatens to delay next week's launch of a commercial supply ship for NASA.

NASA said Friday night that a backup computer on the outside of the orbiting lab is not responding to commands.

The main computer, called an MDM or multiplexer-demultiplexer, is working fine, and the six-man crew is in no danger, officials said. But these computers control some robotic functions that would be needed for the upcoming supply run by SpaceX, one of two U.S. companies contracted by NASA to keep the space station well stocked. A backup computer would need to be operating for redundancy of those robotic systems.

SpaceX is supposed to launch the unmanned Dragon capsule on Monday from Cape Canaveral. It contains nearly 5,000 pounds of supplies and science experiments.

The mission is already a month late because of extra prep time needed by the California company and unrelated damage to an Air Force radar-tracking device needed for rocket launches.

Late Friday, Mission Control was trying to determine whether the computer can be repaired or must be replaced. A replacement would have to be accomplished by spacewalking astronauts.



Mission 'Progress 55' lifts off from Kazakhstan on a Russian Soyuz spacecraft to deliver cargo and crew supplies to the International Space Station


NASA is still aiming for a Monday launch by SpaceX. But that could change, depending on the status of the bad computer.

Astronauts use the space station's big robot arm to grab onto the Dragon capsule and attach it to the outpost.

The space station is currently home to two Americans, one Japanese and three Russians.

NASA is paying Space Exploration Technologies Corp. — or SpaceX — and the Virginia-based Orbital Sciences Corp. to make space station deliveries. Russia, Japan and Europe also conduct occasional supply runs.

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Online:

NASA: http://spaceflight.nasa.gov


http://news.yahoo.com/space-station-computer-outage-may-force-spacewalk-031328392.html

[Buster's Uncle]

NASA Mulls Unplanned Spacewalk to Fix Space Station Computer Outage
SPACE.com
by Tariq Malik, Managing Editor  6 hours ago



The International Space Station suffered a cooling system malfunction on Dec. 11, 2013. This file photo of the station was taken in May 2010 by NASA space shuttle astronauts.



A backup computer outage on the International Space Station is forcing NASA to discuss plans for a possible spacewalk repair by astronauts in orbit, a move that could delay the planned Monday launch of a commercial SpaceX cargo ship to the orbiting lab.

NASA officials decided Saturday (April 12) to avoid a final decision on whether to delay the unmanned SpaceX Dragon launch as station engineers weigh options to fix the backup computer, which stopped responding to commands Friday and is part of the station's robotics system. SpaceX currently aims to launch the Dragon capsule from Florida's Cape Canaveral Air Force Station at 4:58 p.m. EDT (2058 GMT) on Monday. Station astronauts plan to capture the craft with a robotic arm on Wednesday.

"Station program officials, flight controllers and teams of engineers are working to determine whether there is any risk to launching the SpaceX cargo craft Monday," read a NASA statement released Saturday. The main issue is whether the space station's robotics system has enough redundancy without the backup computer.

Because the station's robotic arm is vital to capturing the Dragon spacecraft and attaching it to the space station, NASA is studying the issue extremely closely. The space agency rescheduled two Sunday morning press conferences on the upcoming SpaceX mission to later Sunday afternoon while engineers discuss their options.

Astronauts on the space station would have to perform a spacewalk to fix or replace the computer. The MDM computer repair is one of 12 scenarios NASA astronauts regularly train for before flying to the space station.

The problem cropped up late Friday, when a backup computer known as a Multiplexer-Demultiplexer, or MDM for short, stopped responding to commands. The device is located on the station's exterior and serves as a backup controller for the Mobile Transporter, a railcar that moves the Canadarm2 robotic arm along the space station's backbone-like main truss.



A SpaceX Dragon commercial cargo craft is seen in the the grips of the Canadarm2 before being released May 31, 2012. The space station's robotic arm is used to capture and release SpaceX Dragon cargo ships during their resupply missions.


The primary computer that controls the station's Mobile Transporter is working perfectly, NASA officials wrote in the status update. But the backup computer, called EXT-2, failed a routine health check on Friday.

The failed MDM backup computer is one of more than a dozen on the station's exterior "that route computer commands to various systems on the outpost," according to the NASA statement.

SpaceX's current Dragon mission to the space station has been delayed since March due to an unrelated damage to ground radar equipment used during launches from the Cape Canaveral Air Force Station. This mission, called Commercial Resupply Services 3, is SpaceX's third resupply mission for NASA since 2012 under a $1.6 billion contract.

If SpaceX does not launch its Dragon mission on Monday, the mission could potentially target a backup launch day of Friday, April 18. But that will depend on any NASA plans for a spacewalk repair.

SpaceX plans to fly at least 12 Dragon cargo missions to the space station for NASA under its contract. Another company, the Dulles, Va.-based Orbital Sciences Corp., has a $1.9 billion deal with NASA to provide eight resupply flights using its own Antares rockets and unmanned Cygnus spacecraft.


http://news.yahoo.com/nasa-mulls-unplanned-spacewalk-fix-space-station-computer-180145868.html