Space station cooling system suddenly shuts down

Aug 01, 2010 By MARCIA DUNN , AP Aerospace Writer
This Feb. 19. 2010 file photo provided by NASA shows the International Space Station with Earth's horizon as a backdrop. Several power systems have been shut down aboard the International Space Station after a cooling system malfunctioned. NASA says in a posting on its website that one of two cooling loops aboard the space station was shut down Saturday, July 31, 2010. A module that pumps ammonia coolant to prevent equipment from overheating was still shut down early Sunday, Aug. 1. (AP Photo/NASA, File)

(AP) -- Half of the International Space Station's cooling system suddenly shut down during the weekend, forcing the astronauts to power down equipment and face the likelihood of urgent spacewalking repairs.

After huddling Sunday, managers gave preliminary approval for a pair of spacewalks, the first of which would take place later this week. Two of the Americans on board were already scheduled to conduct a spacewalk Thursday for routine maintenance, though the repairs would supersede the original chores.

Officials stressed that the six occupants were in no danger, and that the orbiting complex was in a stable situation. Much of the station is operating on a single string, however, with no safeguard in case of further failures.

The trouble arose Saturday night, when one of the two ammonia-fed cooling loops shut down. Alarms sounded throughout the sprawling outpost as the circuit breaker for the pump in that line tripped, causing the pump to stop working.

The cooling system is critical for on-board operations. The two ammonia lines ensure that all the station's electronic equipment does not overheat.

Astronaut Tracy Caldwell Dyson hustled through the equipment shutdown procedures and, with crewmate Douglas Wheelock, installed a jumper cable to keep all the rooms cool.

Flight controllers tried to restart the disabled ammonia pump early Sunday, but the circuit breaker tripped again. No further repair attempts were planned, at least for now. In fact, the were allowed to sleep in because of all the late-night disruptions.

Any repairs later this week will involve replacing that ammonia pump, a difficult job that would require two spacewalks. Two spare pumps are stored on the outside of the station.

The first repair spacewalk likely would occur Thursday at the earliest, with the second excursion two or three days later. A final decision on whether to proceed with the task will be made following additional engineering review.

Among the equipment powered off for now: the Global Positioning System circuit, several power converters and a set of devices that route commands to various equipment.

Two of the four gyroscopes initially were shut down - part of the space station's pointing and navigating system. But the crew installed a jumper cable to bring up a third gyroscope, leaving the station in a much more stable position.

On board are three Americans and three Russians.

No space shuttle visits are planned before November. Only two U.S. shuttle missions remain before the fleet is retired; a third and final flight for next summer is under consideration.

Explore further: Innovative use of pressurant extends MESSENGER's mission, enables collection of new data

More information: NASA: http://www.nasa.gov/mission-pages/station/main/index.html

4.8 /5 (5 votes)
add to favorites email to friend print save as pdf

Related Stories

Astronauts remove troublesome cargo container

Apr 15, 2010

(AP) -- After struggling for hours with a balky latching system, shuttle Discovery's astronauts successfully removed a cargo carrier from the International Space Station on Thursday.

Astronauts take 3rd, final spacewalk of mission

Apr 13, 2010

(AP) -- A pair of astronauts finished installing a fresh storage tank outside the International Space Station on Tuesday, accomplishing a main mission objective that required three spacewalks.

NASA schedules four ISS spacewalks

Jan 24, 2007

NASA astronauts are to conduct an unprecedented series of four spacewalks during the next month at the International Space Station.

Astronauts take mission's 3rd and final spacewalk

Sep 06, 2009

(AP) -- Two spacewalking astronauts took on cable and antenna work at the international space station Saturday in their final trek outside, but encountered last-minute difficulty with a connector and had ...

Recommended for you

The top 101 astronomical events to watch for in 2015

Dec 24, 2014

Now in its seventh year of compilation and the second year running on Universe Today, we're proud to feature our list of astronomical happenings for the coming year. Print it, bookmark it, hang it on your ...

NASA image: Frosty slopes on Mars

Dec 24, 2014

This image of an area on the surface of Mars, approximately 1.5 by 3 kilometers in size, shows frosted gullies on a south-facing slope within a crater.

User comments : 8

Adjust slider to filter visible comments by rank

Display comments: newest first

Kedas
not rated yet Aug 01, 2010
You would think that passive cooling is more than enough up there. but not so easy to control I assume.
mhenriday
not rated yet Aug 01, 2010
The link to the NASA site provided above does not seem to be functional ; clicking it gives rise to a «page not found» message....

Henri
frajo
1 / 5 (1) Aug 01, 2010
The link to the NASA site provided above does not seem to be functional ; clicking it gives rise to a page not found message....
Henri

Just replace "mission-pages" by "mission_pages" in the URL.
RayWilson
not rated yet Aug 01, 2010
I know it's serious, but maybe they could just open a window and let a breeze through.
ScientistAmauterEnthusiast
not rated yet Aug 01, 2010
It's like having your heater break down whilst being on the sun.
Kedas
not rated yet Aug 02, 2010
Passive cooling: correct approximation?
The solar panels can generate about 8*15kW=120kW(max)
So worst case al this heat energy has to get out again.

So the needed surface to radiate this energy is:
120000W/293K^4/5.67e-8/0.8=359 m²

That is an area of 19 by 19 meters(=57feet)that is way bigger than I thought they would need, did I make a mistake?
Kedas
not rated yet Aug 02, 2010
Found an article about it:
http://science.na...21mar_1/

They eventually have/had 156 square meters. (at least in 2001)
Scott_T
Aug 02, 2010
This comment has been removed by a moderator.
Skeptic_Heretic
not rated yet Aug 02, 2010
Inconsistent cooling, or using passive cooling would actually require more energy to stabilize the orbit of the station than using a standardized cooling mechanism. In space all radiation, if inconsistently radiated, will introduce anomalous trajectories.

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.