Spacewalking Astronauts Replace Dead Computer on Space Station
NASA astronauts Rick Mastracchio (right) and Steve Swanson work outside the International Space Station to replace a dead computer during a spacewalk on April 23, 2014.
Nothing says “astronaut” quite like a spacesuit. Whether it’s the shiny aluminized nylon flight suits worn by the original Mercury Seven astronauts or the pressurized bright orange “pumpkin suits” worn by space shuttle crews, the clothes do make the man or the woman. It’s much more than a look; the suits could be the only thing that separates an astronaut from life or death in case of an emergency. Here’s a look at some spacesuits in NASA’s storerooms.
With the end of the space shuttle program, NASA began working on a spacesuit that astronauts could wear for forays into deep space, beyond where the space station flies. Last month, the agency awarded an 18-month, $4.4-million contract to ILC Dover to design, manufacture and test a new type of spacesuit called the Z-2. Pictured here is a predecessor prototype, the Z-1, which resembles something Buzz Lightyear might have in his closet. The design is intended to be more comfortable and more flexible for spacewalkers than the Extravehicular Mobility Units, or EMU, that spacewalkers wear today.
NASA looked to the U.S. Navy when it came time to design a spacesuit for its first group of astronauts, the Mercury Seven, pictured here, who were selected in 1959. The agency modified a version of high altitude jet aircraft pressure suit. Beneath the shiny layer of aluminized nylon is an inner layer of Neoprene-coated nylon.
It wasn’t enough to simply land on the moon. The Apollo astronauts were tasked to get out of their spaceship and walk around. Three crews even got to drive around in lunar rovers. Their spacesuits were the first to include a liquid-cooled inner garment and an outer layer to protect against micrometeoroid impacts. Pictured here is the iconic shot of Apollo 11 astronaut Buzz Aldrin taken by his crew mate and commander, Neil Armstrong.
NASA dropped pressurized flight suits for space shuttle crews after four test flights. When Vance Brand, Bob Overmyer, Joe Allen and Bill Lenoir blasted off aboard Columbia on Nov. 11, 1982, for the fifth shuttle mission they wore just blue flights suits with oxygen helmets.
After the 1986 shuttle Challenger accident, NASA beefed-up safety requirements, which included a redesign flight suit for astronauts to wear during launch and landing. The so-called “pumpkin suits” evolved into the Advanced Crew Escape Suit, pictured here. The full-pressure suit is based on U.S. Air Force high-altitude pressure suits worn by SR-71 Blackbird and U-2 spy plane pilots. It includes a parachute pack and harness, life raft, life preserver, gloves, oxygen manifolds and valves, boots and survival gear.
To protect astronauts working outside the shuttle or the space station, NASA developed the Extravehicular Mobility Unit, or EMU. It’s more like a self-contained satellite than a spacesuit, offering spacewalkers environmental protection, life support and communications. The two-piece semi-rigid suit, which weighs about 300 pounds, is one of two kinds used on the space station today. The other is one-piece semi-rigid Russian Orlan suit. Astronaut Steve Robinson, attached to the Canadarm2 during STS-114 in 2005, is pictured here.
NASA has studied dozens of spacesuit designs over the years, including the AX-5, pictured here, which was developed at the Ames Research Center in California. The high-pressure suit uses hard metal and a composite rigid exoskeleton design.
Many old spacesuits end up in museums. But this decommissioned Russian Orlan suit took on a new life as a low-cost satellite. Dubbed SuitSat, the discarded spacesuit was filled with old clothes, outfitted with a radio transmitter and released into Earth orbit on Feb. 3, 2006. It was eventually pulled back into the atmosphere by the planet’s gravity and burned up.
A pair of NASA astronauts replaced a dead backup computer on the International Space Station during a short spacewalk Wednesday (April 23) to restore a critical computer system back to full strength.
NASA astronauts Rick Mastracchio and Steve Swanson made quick work of their repair during the spacewalk, removing the faulty station computer and installing a spare less than an hour after floating outside the orbiting laboratory at 9:56 a.m. EDT (1356 GMT).
"It looks like a good day for you guys to take a walk in space," Mission Control radioed the astronauts as the spacewalk began. The spacewalk was slated to last only 2.5 hours. [See photos from today's spacewalk]
Mastracchio and Swanson replaced a computer known in NASA parlance as a Multiplexer-Demultiplexer, or MDM. The device is a backup computer for routing commands to systems supporting the space station's solar arrays, robotic arm rail car and other critical systems along the station's backbone-like main truss.
The 10-year-old MDM computer failed on April 11 during a standard test. The primary computer in the system is working fine, but NASA station flight controllers ordered today's repair spacewalk to restore redundancy in the system.
"Looks like we've got a new MDM," Mastracchio said as he finished the job.
A quick test showed the new computer was working fine.
"Oh wonderful," Mastracchio said.
There are 45 MDM computers on the International Space Station, with 21 of them located on the orbiting lab's exterior and the rest installed inside the station's habitable area. Replacing the MDM computer boxes is one of 12 core space station repair skills astronauts learn before launch, NASA officials have said.
Despite their swift work, the spacewalkers did take time to marvel at the bright blue Earth below. At one point, Mastracchio reminded Swanson to take a look down at the sunlit Earth.
"Where are we?" Mastracchio asked Mission Control later. The answer: Over South America.
"A great view," the astronaut replied.
NASA astronaut Rick Mastracchio (center) floats above the Quest airlock outside the International Space Station while crewmate Steve Swanson (partially obscured) is nearby during a computer repair spacewalk on April 23, 2014.NASA TV
Wednesday's 2.5-hour spacewalk was substantially shorter than the typical six-hour excursions astronauts take outside the International Space Station. That's because the MDM computer replacement was sole goal for Mastracchio and Swanson
"We want to get this job done as quickly as we can, so we didn't want to add a whole bunch of things for this team to sort out," NASA space station program manager Mike Suffredini told reporters on Friday (April 18).
Suffredini said the decision for a short spacewalk is also a safety measure for Mastracchio and Swanson, who are using spacesuits that have new water filters and fan pump systems. That maintenance was performed in the wake of a harrowing June 2013 spacewalk in which a water leak flooded the helmet of Italian astronaut Luca Parmitano, nearly drowning him. NASA engineers suspect contamination in the water line caused the leak.
"I feel pretty strongly that we've sorted out the root cause and that our suits are in good shape," Suffredini said.
Today's space station repairs marked the ninth career spacewalk for Mastracchio, and the fifth spacewalk for Swanson. Japanese astronaut Koichi Wakata and Russian cosmonauts Mikhail Tyurin, Oleg Artemyev and Alexander Skvortsov round out the crew. The spacewalk came on the heels of two other major events for the six-man crew on the International Space Station.
On Sunday (April 20), an unmanned SpaceX Dragon cargo ship arrived at the station carrying 2.5 tons of fresh supplies and gear for the orbiting lab's crew. Then earlier today, at 4:58 a.m. EDT (0858 GMT), a robotic Russian Progress 53 cargo ship was due to undock from the station and park itself about 311 miles (500 kilometers) from the orbiting lab to test its new Kurs automated docking system. The Progress spacecraft is due to return to the space station on Friday (April 25).
Original article onSpace.com.
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