Sunday, December 21, 2014
YOLO COUNTY NEWS
99 CENTS

Spacewalking repair halts station leak — for now

Astronaut Christopher Cassidy, foreground, holds a power wrench as he stows away a suspect coolant pump Saturday on the International Space Station. Thomas Marshburn is at left.   AP photo

In this image made from video provided by NASA, astronaut Christopher Cassidy, foreground, holds a power wrench as he stows away a suspect coolant pump on the International Space Station on Saturday, May 11, 2013. Thomas Marshburn is at left. The two astronauts made the spacewalk to replace the pump after flakes of frozen ammonia coolant were spotted outside the station on Thursday. (AP Photo/NASA)

By
From page A2 | May 12, 2013 |

CAPE CANAVERAL, Fla. (AP) — Astronauts making a rare, hastily planned spacewalk replaced a pump outside the International Space Station on Saturday in hopes of plugging a serious ammonia leak.

The prospects of success grew as the minutes, then hours passed and no frozen flecks of ammonia appeared. Mission Control said it appeared as though the leak may have been plugged, although additional monitoring over the coming weeks will be needed before declaring a victory.

“I will tell you that we’re happy. We’re very happy,” said Joel Montalbano, NASA’s deputy space station program manager. “We didn’t see any obvious signs of a leak, but it’s going to take some time … for us to look at the system, evaluate the system and make sure we did, indeed, stop the leak.”

Montalbano expects it will take “a good four weeks, five weeks, maybe even a few weeks longer.”

“Obviously, the longer you go, the more confidence you get,” he told reporters.

Christopher Cassidy and Thomas Marshburn installed the new pump after removing the old one suspected of spewing flakes of frozen ammonia coolant two days earlier. They uncovered “no smoking guns” responsible for the leak and consequently kept a sharp lookout for any icy flecks that might appear from the massive frame that holds the solar panels on the left side.

“Let us know if you see anything,” Mission Control urged as the fresh pump was cranked up. Thirty minutes later, all was still well. “No snow,” the astronauts radioed.

“We have our eyes on it and haven’t seen a thing,” Marshburn said.

NASA said the leak, while significant, never jeopardized crew safety. But managers wanted to deal with the trouble now, while it’s fresh and before Marshburn returns to Earth in just a few days.

The space agency never before staged such a fast, impromptu spacewalk for a station crew. Even during the shuttle program, unplanned spacewalks were uncommon.

The ammonia pump was the chief suspect going into Saturday’s spacewalk. So it was disheartening for NASA, at first, as Cassidy and Marshburn reported nothing amiss on or around the old pump.

“All the pipes look shiny clean, no crud,” Cassidy said as he used a long, dentist-like mirror to peer into tight, deep openings.

“I can’t give you any good data other than nominal, unfortunately. No smoking guns.”

Engineers determined there was nothing to lose by installing a new pump, despite the lack of visible damage to the old one. The entire team — weary and stressed by the frantic pace of the past two days — gained more and more confidence as the 5 1/2-hour spacewalk drew to a close with no flecks of ammonia popping up.

“Gloved fingers crossed,” space station commander Chris Hadfield said in a tweet from inside. “No leaks!” he wrote a half-hour later.

Flight controllers in Houston worked furiously to get ready for Saturday’s operation, completing all the required preparation in under 48 hours. The astronauts trained for just such an emergency scenario before they rocketed into orbit.

This area on the space station is prone to leaks.

The ammonia coursing through the plumbing is used to cool the space station’s electronic equipment. There are eight of these power channels, and all seven others are operating normally.

Life for the six space station residents has been pretty much unaffected since Thursday’s ammonia shower. The loss of an additional power channel, however, could threaten science experiments and backup equipment.

“We may not have found exactly the smoking gun,” Cassidy said, “but to pull off what this team did yesterday and today, working practically 48 straight hours, it was a remarkable effort on everybody’s behalf.”

NASA officials remain mystified as to why the leak erupted. Ammonia already had been seeping ever so slightly from the location, but the flow increased dramatically Thursday.

Montalbano did not know, as of Saturday evening, how much ammonia was lost. Another spacewalk will be needed to replenish the supply.

With the repair work behind them, the astronauts and ground controllers turned their attention to the impending departure of three of the six crewmen.

Marshburn has been on the space station since December and is set to return to Earth late Monday, along with Hadfield, a Canadian, and Russian Roman Romanenko. Cassidy is a new arrival, on board for just 1½ months.

By coincidence, the two Americans performed a spacewalk at this troublesome spot before, during a shuttle visit in 2009.

“This type of event is what the years of training were for,” Hadfield said in a tweet Friday. “A happy, busy crew, working hard, loving life in space.”

 ————

By Marcia Dunn, AP aerospace writer

Comments

comments

The Associated Press

  • Recent Posts

  • Enter your email address to subscribe to this newspaper and receive notifications of new articles by email.

  • .

    News

     
    What’s new at UCD? Construction projects abound

    By Tanya Perez | From Page: A1 | Gallery

    No-nonsense Musser voted Citizen of the Year

    By Dave Ryan | From Page: A1 | Gallery

     
    Sharing a meal, and so much more

    By Anne Ternus-Bellamy | From Page: A1 | Gallery

    Brinley Plaque honors environmental stalwart

    By Dave Ryan | From Page: A1 | Gallery

     
    North Korea proposes joint probe over Sony hacking

    By The Associated Press | From Page: A2

    AP sources: Cops’ killer angry over Garner death

    By The Associated Press | From Page: A2

     
    Raul Castro: Don’t expect detente to change Cuban system

    By The Associated Press | From Page: A2

    Police seek help in finding runaway twin girls

    By Enterprise staff | From Page: A2

     
    Downtown crash results in DUI arrest

    By Lauren Keene | From Page: A2

    March trial date set in Davis molest case

    By Lauren Keene | From Page: A2

     
    Enterprise plans Christmas, New Year’s holiday hours

    By Enterprise staff | From Page: A3

     
     
    Luminaria display planned in West Davis

    By Enterprise staff | From Page: A3

    Soup’s On will benefit NAMI-Yolo

    By Enterprise staff | From Page: A3

     
    Pedal around Davis on weekly bike ride

    By Enterprise staff | From Page: A3

     
    Supplies collected for victims of abuse

    By Enterprise staff | From Page: A3

    Donors, volunteers honored on Philanthropy Day

    By Special to The Enterprise | From Page: A3 | Gallery

     
    Surprise honor is really nice, dude

    By Enterprise staff | From Page: A5 | Gallery

     
    Konditorei presents free holiday concert

    By Enterprise staff | From Page: A5

    .

    Forum

     
    E-cigs surpass regular cigarettes among teens

    By The Associated Press | From Page: B4

    It’s not a pretty picture

    By Creators Syndicate | From Page: B4

     
    Google me this: Should I hit that button?

    By Marion Franck | From Page: B4

    Too late to pick a fight

    By Creators Syndicate | From Page: B5

     
    All police need to humanize

    By Letters to the Editor | From Page: A10

    Are we only a fair-weather bike city?

    By Letters to the Editor | From Page: A10

     
    Join us in making our world more just

    By Special to The Enterprise | From Page: A10

     
    Tom Meyer cartoon

    By Debbie Davis | From Page: A10

    The electronic equivalent of war

    By Special to The Enterprise | From Page: A11

     
    The Green House effect: Homes where the elderly thrive

    By New York Times News Service | From Page: A11

    .

    Sports

     
    Stenz shines as DHS girls take a tournament title

    By Enterprise staff | From Page: B1 | Gallery

    Aggie Manzanares not quite finished carrying the rock

    By Bruce Gallaudet | From Page: B1 | Gallery

     
    UCD women look to improve, despite game at No. 7 Stanford

    By Bruce Gallaudet | From Page: B1 | Gallery

    Second-half run spurs Aggie men to 8-1

    By Enterprise staff | From Page: B1

     
    49ers fall to San Diego in overtime

    By The Associated Press | From Page: B10

    .

    Features

    .

    Arts

    .

    Business

    Marrone Bio expands its product reach in Latin America

    By Enterprise staff | From Page: A4

     
    Sierra Northern Railway names CEO

    By Special to The Enterprise | From Page: A4

    Sink your teeth into Vampire Penguin

    By Wendy Weitzel | From Page: A4 | Gallery

     
    .

    Obituaries

    .

    Comics

    Comics: Sunday, December 21, 2014

    By Creator | From Page: B8