Posted on by Nancy Atkinson

Spacewalkers Remove Failed Pump Module on ISS; Two More EVAs Needed to Complete Repairs

Image above: Expedition 24 Flight Engineers Doug Wheelock (right) and Tracy Caldwell Dyson work to replace a failed ammonia pump module outside of the International Space Station. Credit: NASA TV

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Overcoming a disappointing spacewalk last weekend, today astronauts Doug Wheelock and Tracy Caldwell Dyson successfully removed the failed ammonia coolant pump module on the S1 truss of the International Space Station. But NASA managers said that at least two more EVAs will be required to complete all the repairs to the critical cooling system. Earlier, it was hoped that two spacewalks total would allow enough time, but it will take at least four. “There were a number of challenges in the first EVA that set us back, but as we looked closer at this, we were hedging our bets at how many EVAs we had ahead of us,” said Spacewalk officer David Beaver at a press briefing following the successful EVA today. “As we have done more and more work in laying this out in a stepwise fashion, it became clear to us early on that this was a much bigger set of EVAs than we originally made time for.”

He added that on orbit, the astronauts have stopped all research in order to save on the cooling system. The complex systems keeps the station from overheating and the six-member crew has relied on just one — instead of the usual two pumps –to handle the cooling ever since the one pump failed during a power surge on July 31.

“The system has been kind to us and we haven’t had any more failures,” Beaver said.

The spare pump will be installed on the S1 truss during a spacewalk that is now scheduled for Monday – originally it was set for Sunday, but NASA managers decided an extra day would help both the astronauts and the teams on the ground preparing for the EVAs.

Wheelock and Caldwell Dyson were able to close the quick disconnect valve for the final fluid connector for the failed ammonia pump module, and then detach the final fluid line from the failed ammonia pump module – which was the problem that couldn’t be overcome on the first spacewalk.

The two astronauts then extracted the pump module and stowed on another location on the truss, and Caldwell Dyson prepared the spare pump for installation on the next spacewalk on Monday.

The spacewalk lasted 7 1/2 hours, slightly shorter than Saturday’s eight-hour marathon, the longest EVA at the ISS without a space shuttle present. Wheelock and Dyson had to use decontamination procedures after the spacewalk just in case some ammonia leaked on their suits.

In response to the power-saving reconfiguration that has had to be done, the science team worked quickly to establish a plan to preserve experiment samples in the Japanese Experiment Module freezer. The on-orbit crew was able to transfer all the samples from the freezer in the Kibo laboratory to an operating freezer. No sciences samples were lost due to the pump module anomaly.

While the crew schedule has been interrupted to support the newly added spacewalks, the payload ground teams have been working closely with mission controllers to preserve and re-plan high priority activities. Other activities that can be rescheduled with little or no impact are being postponed to a later date.

Posted on by Nancy Atkinson

NASA Schedules Two “Emergency” EVA’s to Fix Cooling System

Location of the pump module on the S-1 truss that failed. Credit: NASA

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*Updated at 11 pm CDT — dates have changed for EVAs.
Two spacewalks will be required to remove and replace a pump on a critical cooling system on the International Space Station, and NASA is hoping to have station astronauts and ground teams ready by Thursday, August 5 Friday, August 6 for the first EVA. The pump module failed over the weekend, prompting a shift to a backup system, while other systems were shut down as a precaution. The backup system is working perfectly, and having a second system failure is highly unlikely, but NASA does not like to operate on a “single-string” system without redundancy. “Having another failure would be a serious situation for the program that we want to avoid,” said ISS program manager Mike Suffredini.

Update:
NASA had originally scheduled the first EVA for Thursday, August 5 and the second for Sunday, but decided late Monday that they needed more time for both astronauts and ground crews to prepare. Now, the first spacewalk will be Friday morning, starting at 6:55 a.m. EDT, (1155 GMT) with the second EVA on Monday, August 9.

An EVA was already scheduled for August 5 for astronauts Doug Wheelock and Tracy Caldwell Dyson to install part of a robotic crane and to prepare for a new module due to arrive in November aboard space shuttle Discovery. But that work will be postponed in order for the astronauts to do the priority fix.

“Typically, we allow two weeks to prepare for this type of EVA, but we decided to take advantage of having an EVA already scheduled, so this is a very aggressive approach,” said Flight Director Courtenay McMillan, who is leading the team supporting the spacewalk.

This type of EVA is part of what is called the “Big 14” set of contingency spacewalks that all ISS astronauts train for in the event of system failures like the one that happened on Saturday.

Suffredini said he is confident everyone can be ready. “The crew is in great spirits and are ready to do this,” he said. “These Big 14 EVA’s cover major systems repairs that an increment crew might have to do without the shuttle there. They train for both specific and generic spacewalks, and this particular one they have trained for. So they have some familiarity with the tasks they will be asked to do.”

Additionally all the operations teams have been working around the clock to prepare for the fix. “The ops team is full up for support,” Suffredini said. “If you were to go in the control room, it looks more like a shuttle flight is going on right now. We do train for these kinds of anomalies, and have been fortunate that we haven’t had to deal with anything like this before, but we have good plans in place.”

Spare Pump Module, with grapple fixture. Credit: NASA

The pump — which was installed in October 2002 — failed Saturday night after a spike in electrical current tripped a circuit breaker. When the 350 kg (780-pound) pump failed, it shut down half of the station’s cooling system. Efforts to restart the pump, which feeds ammonia coolant into the cooling loops to maintain the proper temperature for the station’s electrical systems and avionics, were not successful. Suffredini said data suggests the motor is not frozen, as it did begin to pump when they did the restart, so that tells them there is likely a short in the electrical system.

The station’s crew worked with Mission Control to put the station in a stable configuration. The crew, which is in no danger, has resumed normal work activities and most of the systems are up and running. One freezer was shut down, but frozen specimens which are to be returned to Earth were transferred to another freezer.

McMillan said astronauts Cady Coleman and Sunny Williams are working today in the Neutral Buoyancy Lab — the big pool where astronauts train for EVAs — doing development runs for the emergency EVAs.

“They are doing the tasks that they forsee we’ll need to do, trying to work out details of the timeline,” she said. “And depending on how things go today we’ll see if we’ll be ready for the EVA.”

There are spare pump modules already on board the station, and Suffredini said that if more modules are needed, they can fit on board the Japanese HTV resupply vehicles or SpaceX’s cargo vehicle, and don’t need to be brought up by the space shuttle.

Posted on by Nancy Atkinson

Space Station Cooling System Shuts Down

Space Station
The International Space Station in 2010. Credit: NASA

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One of the International Space Station’s external cool system pumps quit working late Saturday, likely due to mechanical failure. This triggered subsequent shutdowns in other systems. Teams on the ground are working with the six astronauts on board the station to troubleshoot the issue, but it appears at least two spacewalks will be required to remove and replace the pump. NASA officials said the problem will have to be resolved quickly, as the cooling system is extremely important for all the station’s systems. This is a redundant system, so the backup loop is now cooling the station and the crew is in no danger, but NASA does not like to work any systems “single string,” i.e., with no backup.

NASA tried restarting the pump Sunday morning, but it did not work. There are two spare pumps on orbit. ISS astronauts Doug Wheelock and Tracy Caldwell Dyson had been already scheduled to make a spacewalk on August 5 to install part of a robotic crane and to do preparation work get ready for a new module (the Permanent Logistics Module) that is due to arrive in November aboard space shuttle Discovery.

EVA teams are now looking at using the August 5 space walk for the first half of the repairs, followed by the second EVA on August 7 (Saturday). The spacewalks need special planning since the system is in a reduced power configuration.

One of the radiators which allow for cooling on board the ISS. Credit: NASA

The space station features two independent coolant loops that use ammonia circulating through huge radiators to dissipate the heat generated by the station’s electronic systems, primarily from the labs. Each loop is fed by a large tank of ammonia that includes an internal bellows pressurized by nitrogen. That pressurization system allows the loops to handle the periodic expansion and contraction of the ammonia coolant due to temperature changes when the station goes from sunlight to shadow while in orbit.

Back in April a valve failed on the coolant system, but the teams were able to troubleshoot and fix the problem without a spacewalk.

A status update from NASA listed several other systems that required powerdowns to as a result of the cooling loop shutdown in order to thermally protect them:

Redundant power to four CQs (Crew Quarters), three in Node-2, one in Kibo JPM, with both fans in each CQ remaining functional but zero fault-tolerant (crew is still Go for CQ use). Due to loss of heater power, MBS (Mobile Base System), SSRMS (Space Station Remote Manipulator System), and SPDM (Special Purpose Dexterous Manipulator) are currently zero fault-tolerant. Communications systems, but there could be some issues with possible overheating. No video will be available fromNode-2, Node-3, the Columbus and Japanese modules.

Posted on by Nancy Atkinson

Tools Get Loose During ISS Spacewalk

A Russian spacewalker works outside the Pirs docking compartment after beginning the first Expedition 24 spacewalk. Credit: NASA TV

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Two Expedition 24 cosmonauts conducted a six-and-a-half hour spacewalk outside the International Space Station earlier today, outfitting the newest module for future dockings of Russian vehicles. Flight Engineers Fyodor Yurchikhin and Mikhail Kornienko set up the Kurs automated rendezvous on the Rassvet module, which was delivered on the last space shuttle mission to the ISS. Additionally, the pair of spacewalkers routed and mated Command and Data Handling cables on the Zvezda and Zarya modules. While they also purposefully jettisoned an old camera, two other objects got loose and floated away from the astronauts. The objects are being tracked to make sure they will not pose a threat to the station later.

One was tentatively identified as a cable clamp, left outside the station from a previous Russian spacewalk, and the other object was not conclusively identified.

This was the 147th spacewalk at the ISS for station assembly and maintenance. This was Kornienko’s first spacewalk and Yurchikhin’s fourth. Yurchikhin’s first three spacewalks occurred when he was commander of Expedition 15 in 2007.

The camera that was tossed away was replaced, and the new camera will provide better television views of the final approach and docking of future European Automated Transfer Vehicles carrying cargo to the station.

Another spacewalk will take place next week, on August 5, with US astronauts Doug Wheelock and Tracy Caldwell Dyson getting the chance to go outside. They will install a power cable to the Unity module in preparation for the installation of the Permanent Multipurpose Module during the STS-133 mission in November. A Portable Data Grapple Fixture will be installed on the Zarya module that will extend the reach of Canadarm2, the station’s robotic arm, and increase a spacewalker’s access for assembly or maintenance work. They also will jettison multi-layer insulation removed for the grapple fixture installation and will mate power connectors to Zarya.

Source: NASA

Posted on by Nancy Atkinson

ISS Will Be in Constant Sunlight the Next Few Days

I just took a look at Heaven’s Above to check on when I could see the International Space Station this weekend, and got the surprise of my life! On Saturday (June 26) I have 5 — count ’em — 5 opportunities to see it! That is completely unusual, so what’s up? For the next few days, the International Space Station (ISS) will be orbiting Earth in constant sunlight, as its orbit lines up with Earth’s day-night terminator. Therefore, the ISS will be putting on an incredible show the next few nights, since it will be constantly illuminated, and will be visible in the night sky every single time it passes overhead. Some observers will be able to see the space station 3, 4 — or like me — even 5 times a night. Check on Heaven’s Above, or NASA’s NASA has a Skywatch page where you can find your specific city to look for satellite sighting info.

Spaceweather.com, has a Satellite Tracker Tool. Just put in your zip code (good for the US and Canada) to find out what satellites will be flying over your house.

I’m expecting you all are going to be submitting some great astrophotos of the ISS during the next few days! Send ’em in!

Posted on by Nancy Atkinson

100th Launch to the International Space Station

The Soyuz TMA-19 vehicle blasted off from Baikonur Cosmodrome in Kazakhstan today to bring three new crew members to the International Space Station. This was the 100th launch of missions in support of space station assembly, resupply and crew exchanges. The rocket lit up the early morning sky in Kazakhstan at 3:35 a.m. Wednesday local time, (5:35:19 p.m. EDT and 9:35 pm GMT on Tuesday). The Soyuz took eight and a half minutes to reach orbit, but it will take about 2 days to catch up to the ISS.
Continue reading “100th Launch to the International Space Station”

Posted on by Nancy Atkinson

Unusual Views of the Soyuz Rocket

'Up, up the long delirious burning blue...' View from the Soyuz flame trench by 'Astro_Wheels,' astronaut Douglas Wheelock.

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Two NASA astronauts and a Russian cosmonaut will launch to the International Space Station later today, and astronauts Douglas Wheelock has been able to get up close and personal with the Soyuz rocket that will take them there. He’s taken a few pictures of his rocket from unusual vantage points and posted them on Twitter, and is sharing his prelaunch experiences, too (@Astro_Wheels). Wheelock has big shoes to fill in the Twitter and picture-taking department, as JAXA astronaut Soichi Noguchi set a new standard in making his time on board the ISS a shared experience through images and social media. More pics below, plus a newly released video by NASA of the landing of the Soyuz that brought the Noguchi, Soyuz Commander Oleg Kotov and TJ Creamer back home. It’s a view of the landing not normally seen.

'The work goes on, the cause endures, the hope still lives, and the dream shall never die. T minus 42 hours...' Tweeted Wheelock.

For the next crew heading to the ISS, which will bring the crew size back to six at the space station, veteran cosmonaut Fyodor Yurchikhin, Wheelock and Shannon Walker are scheduled for liftoff aboard the Soyuz TMA-19 spacecraft from the Baikonur Cosmodrome in Kazakhstan at 5:35:19 p.m. EDT (9:35 pm GMT) (3:35:19 a.m. June 16 local time Kazakhstan).

Including manned and unmanned missions, this will be the 100th launch supporting space station operations since assembly began in 1998.

Posted on by Nancy Atkinson

Incredible Image: Atlantis and ISS Transit the Sun

Atlantis and the ISS transit the Sun. Credit: Thierry Legault www.astrophoto.fr

Here are some incredible images of Atlantis and the International Space Station captured as it transit the Sun.

You can also view space from where you are. You just need a good telescope for that. Take a look at these cool and amazing telescopes from Amazon.com.

French astrophotographer Thierry Legault has done it again. He captured a view of space shuttle Atlantis and the International Space Station crossing the face of the Sun on May 16, 2010 about 50 minutes before the shuttle docked with the space station. Legault took the image from Madrid, Spain at 13:28:55 UT. “Atlantis has just begun the ‘R-bar pitch maneuver,'” Legault wrote on his website, “as the shuttle performs a backflip that exposes its heat-shield to the crew of the ISS that makes photographs of it; since its approach trajectory is between the ISS and the Earth, this means that we are seeing Atlantis essentially from above, with the payload bay door opened.”

Since this may be Atlantis’ last flight to space, the image is especially poignant.

See below for the full image, and make sure you go to Legault’s website and watch the movie of how quickly the pair of spacecraft actually flew across the face of the Sun — like the blink of an eye! It’s amazing he was able to capture this incredible image at all, not to mention how clear and sharp the two spacecraft are in the photo, against the face of the otherwise spotless Sun. The shuttle’s tail is even visible!

Legault said he used a Takahashi TOA-150 refractor (diameter 150mm, final focal 2500mm), Baader Herschel prism and Canon 5D Mark II camera, at an exposure of 1/8000s at 100 ISO, extracted from a series of 16 images (4 images/s) started 2 seconds before the predicted transit time.

Full image of the Sun, with transiting shuttle and ISS. Credit: Thierry Legault www.astrophoto.fr

Take time to browse through Legault’s impressive collection of spacecraft photography, including an amazing 3-D movie of the ISS.

Posted on by Nancy Atkinson

Stunning Look at ISS and Docked Disovery — From the Ground!

ISS with shuttle Discovery docked on April 8, 2010. Credit: Ted Judah

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This has to be one of the clearest close-up shots of the International Space Station ever taken from the ground! Plus it has the added bonus of having space shuttle Discovery docked to the station. Ted Judah, who lives in northern California captured this image — one of 150 he took during the an ISS pass over his observatory during the recent STS-131 mission. Here’s Ted’s description:

The ISS came into the morning light over the Pacific Ocean just off the coast of northern California and was tracking north-east as it passed directly over my sea-level observatory. I was lucky there was no fog. I have a Canon 30D SLR and Celestron 11″ Schmidt-Cassagrain on an equatorial mount. I track manually and use my precisely-aligned finderscope to aim – when the ISS is in the crosshairs I shoot like crazy. Of the 150 shots I took, less than half have the ISS in frame.

Ted told me he was “stoked” to get such a clear image. Who wouldn’t be?? Nice work, Ted!

Ted is not new to trying to capture the ISS. He won one of “Phil’s Picks” (Bad Astronomer Phil Plait) in Celestron’s “Capture the Universe” contest with another image of the ISS.

Also, Ted has contributed a couple of podcasts to 365 Days of Astronomy, and one of my all-time favorite podcasts is Ted’s description of how he and his family built an observatory out on his father-in-law’s farm.

Here’s another shot Ted took during the same pass:

The ISS and shuttle Discovery during the STS-131 mission. Credit: Ted Judah

Thanks Ted, for sharing your wonderful images!