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From: "Moon, Larry J. (JSC-EA411)" <larry.j.moon@nasa.gov>
Date: December 26, 2013 9:39:36 AM CST
To: "Moon, Larry J. (JSC-EA411)" <larry.j.moon@nasa.gov>
Subject: FW: NASA and Human Spaceflight News Dec. 26, 2013
Hope everyone had a very Merry Christmas.Remember our next Retirees monthly luncheon will be delayed until January 9th, the second Thursday next month only, since the first Thursday fall on the day after New Years Day!NASA and Human Spaceflight NewsThursday – Dec. 26, 2013HEADLINES AND LEADSJob done. Happy Christmas spacewalkersCharles Black -- SENAstronauts Rick Mastracchio and Michael Hopkins completed a spacewalk yesterday to fit a spare ammonia pump to the International Space Station (ISS).The new pump was successfully restarted by flight controllers at NASA's Johnson Space Center last night and a NASA statement confirmed the new pump was working properly. The pump is part of the Station's two external cooling loops which circulate ammonia outside the orbiting outpost to keep both internal and external equipment cool.Christmas in Space: Astronauts Celebrate Holidays in OrbitTariq Malik - SPACE.comSix space travelers living in orbit definitely aren't home for Christmas today, but that doesn't mean they won't get into the holiday spirit on the International Space Station.Spacewalkers wrap up coolant system repairsWILLIAM HARWOOD – CBS NewsTwo astronauts successfully installed a replacement coolant pump aboard the International Space Station Tuesday, wrapping up a high-stakes two-spacewalk repair job and clearing the way for flight controllers to re-activate a critical coolant system.NASA Astronauts Complete Space Station Cooling System Repairs With Second SpacewalkMark Carreau-- Aviation WeekSpacewalking NASA astronauts Rick Mastracchio and Mike Hopkins completed repairs to the six person International Space Station's crippled external thermal control system on Tuesday, wrapping up the complex task in two rather than the three spacewalks originally envisioned.Spacewalkers finish crucial space station repairs in time for ChristmasAlan Boyle -- NBC NewsNearly two weeks after a faulty coolant valve crippled the International Space Station, two NASA astronauts took on a rare Christmas Eve spacewalk to get things back to normal.Christmas Eve spacewalk for repair job endsJethro Mullen - CNNWhile many people spent Christmas Eve doing last-minute shopping, two American astronauts had a more challenging matter to attend to Tuesday.Nasa astronauts repair pump in rare spacewalkBBC NewsTwo US astronauts have successfully repaired a critical cooling system pump at the International Space Station, the US space agency Nasa says.Astronauts successfully replace faulty pump on ISSMonte Morin – Los Angeles TimesNASA astronauts Tuesday successfully replaced a faulty fluid pump in the International Space Station, following two days of work in the open vacuum of space 260 miles above the Earth's surface.Repair gives ISS a cool giftSpacewalkers fix faulty system just in time for ChristmasJames Dean -- FLORIDA TODAYSpacewalkers on Tuesday delivered a welcome Christmas gift to the International Space Station, completing repairs that were expected to fully restore the outpost's hobbled cooling system.Astronauts complete rare Christmas Eve spacewalkMARCIA DUNN -- APCAPE CANAVERAL, Fla. — Space station astronauts repaired a crippled cooling system during a rare Christmas Eve spacewalk Tuesday, braving a "mini blizzard" of noxious ammonia as they popped in a new pump.Russia delay Soyuz-2-1v debutNathaniel Downes and Chris Bergin – NASA Spaceflight.comRussia postponed the debut their new Soyuz-2-1v rocket that was set to launch on Wednesday.Rugged Martian Terrain Chewing Up Curiosity Rover's WheelsMike Wall – SPACE.comEngineers are gearing up to perform a check of the Mars rover Curiosity's six wheels, which have accumulated a lot of wear and tear during the robot's 16 months on the Red Planet.COMPLETE STORIESJob done. Happy Christmas spacewalkersCharles Black -- SENAstronauts Rick Mastracchio and Michael Hopkins completed a spacewalk yesterday to fit a spare ammonia pump to the International Space Station (ISS).The new pump was successfully restarted by flight controllers at NASA's Johnson Space Center last night and a NASA statement confirmed the new pump was working properly. The pump is part of the Station's two external cooling loops which circulate ammonia outside the orbiting outpost to keep both internal and external equipment cool.The Christmas Eve spacewalk lasted 7 hours 30 minutes, and followed on from a 5 hour 28 minute EVA (extra-vehicular activity) by Mastracchio and Hopkins on December 22 when they removed the faulty pump.The spacewalks are a reminder of the challenges of maintaining an orbiting complex and the bravery of the astronauts who live in space orbiting the Earth every 90 minutes -- both inside and outside -- the ISS, travelling at over 27,500 kilometres per hour.Living aboard the station with NASA astronauts Rick Mastracchio and Michael Hopkins are four other spacemen who have made the journey from Earth - Russian cosmonauts Oleg Kotov, Sergey Ryazanskiy and Mikhail Tyurin and Japan Aerospace Exploration Agency (JAXA) astronaut Koichi Wakata.Three of the crew members -- Rick Mastracchio, Koichi Wakata and Mikhail Tyurin -- arrived at the station in November carrying the Olympic torch as part of the build-up to the 2014 Sochi Winter Olympics. Whilst the torch will not be lit during its time in space for safety reasons, the ISS itself lights up the night sky, freely traversing state boundaries as it orbits the planet. It is a beacon of international co-operation, a symbol of what can be achieved by vision, political will and global science.The station celebrated its fifteenth birthday this year. The first module of the Station, Zarya, was put into orbit on November 20, 1998. It was joined a few weeks later when the Space Shuttle delivered Unity, the Station's second module, which was attached to Zarya on December 6. The first crew to live on the Station, Expedition 1, arrived on November 2, 2000. It has been continuously occupied since, a demonstration of how nation states which are oceans apart -- physically and politically -- can combine to build a new world in space. This bright light you can see flying through the night sky reflects both the Sun's light and the unity that can be achieved by the exploration of space.Exploring space brings many direct benefits, increasing our scientific knowledge and delivering services such as mobile telecommunications that benefit consumers every day on Earth. There are also satellites which, in effect, measure the health of the planet and can guide decisions on future policies. Beyond the tangible results there exists the intangible promise of change that could make life better for Earth's inhabitants.Space is for everyone, there are no boundaries and notions of state sovereignty do not exist - a fundamental principle of international space law. As the space station passes in the night sky this Christmas it is a guiding light for what could be achieved in the centuries ahead when nation states combine political will, science and economics - the foundations for an Earth government to manage space exploration and Earth for the benefit of all mankind.Christmas in Space: Astronauts Celebrate Holidays in OrbitTariq Malik - SPACE.comSix space travelers living in orbit definitely aren't home for Christmas today, but that doesn't mean they won't get into the holiday spirit on the International Space Station.The space station's six-man Expedition 38 crew includes two Americans, three Russians and one Japanese astronaut. This year, Christmas falls between two spacewalks — a Christmas Eve spacewalk to fix the outpost's cooling system and a Dec. 27 excursion by Russian cosmonauts — so it is likely a welcome rest in an otherwise busy week."Hey folks, MERRY CHRISTMAS!" NASA astronaut Rick Mastracchio wrote in a Twitter post Sunday, adding that he would write more after finishing the station's "home improvement project" to replace a cooling system pump. He and NASA astronaut Mike Hopkins finished that work in a spacewalk on Tuesday.Mastracchio recently told SPACE.com that he was looking forward to Christmas in space, and expected to call his wife and other family and friends today."First of all, we have great connectivity with our family back home," Mastracchio said in a Dec. 13 interview. "We have an I.P. (Internet protocol) phone, and the ground sets up video conferences with our family on the holiday."Mastracchio said there are decorations on the space station to "liven up the place a little bit," and that the theme of togetherness for the holidays reaches all the way into space."Of course, all six of us will get together and have a special meal, and everyone will pull out whatever special foods we have that are appropriate for the holidays," Mastracchio said. "And we'll just spend time together as a crew and good friends, enjoying each other's company."Mastracchio and his crewmates were expecting some holiday treats on a private Cygnus cargo ship that was slated to launch to space station in mid-December. But that delivery was delayed to early January following the station's cooling system malfunction.NASA spokesman Josh Byerly at the agency's Johnson Space Center in Houston said the space station crew has an off-duty day today, though Mission Control will staffed to support the crew."Mission Control will have a Christmas dinner provided by management," Byerly told SPACE.com in an email.Christmas has been celebrated in space for decades. NASA's Apollo 8 astronauts marked Christmas at the moon in 1968, and Skylab astronauts built a homemade Christmas tree out of food cans in 1973. On the International Space Station, astronauts and cosmonauts have celebrated holidays since the first crew — Expedition 1 — took up residence in 2000.The station crew will have New Year's Day off as well, Byerly said.Spacewalkers wrap up coolant system repairsWILLIAM HARWOOD – CBS NewsTwo astronauts successfully installed a replacement coolant pump aboard the International Space Station Tuesday, wrapping up a high-stakes two-spacewalk repair job and clearing the way for flight controllers to re-activate a critical coolant system."We'd just like to say thanks to all the great folks doing all this hard work to get this space station back up and running," spacewalker Rick Mastracchio radioed as he returned to the Quest airlock module."No, thank you guys," astronaut Doug Wheelock replied from mission control in Houston. "It's the best Christmas ever. Thanks, guys.""Yeah, I'd just like to add to that," Mike Hopkins said from the airlock. "Fantastic work, Merry Christmas to everybody. It took a couple of licks to get her done, but we got it."The only problem of any significance during the seven-hour 30-minute spacewalk was trouble getting one of four ammonia lines disconnected from a so-called jumper box where it was temporarily plugged in during a spacewalk Saturday.Hopkins and Mastracchio finally freed a quick-disconnect fitting holding the half-inch line in place, and were sprayed with ammonia ice crystals trapped in the connector. The toxic chemical posed no threat to the astronauts but they spent a few extra minutes in vacuum to ensure any ice stuck to their suits had time to dissipate before they re-entered the station.The ammonia contamination barely slowed the astronauts down. After freeing the stuck line, Hopkins and Mastracchio finished hooking up all four ammonia lines to the replacement pump module and plugged in five electrical cables. Flight controllers then carried out a so-called "bump" test, briefly spinning up the pump and verifying the operation of internal valves."Good news! The thermal control officer reports a good bump start test on the newly installed pump module," NASA's mission control commentator, Rob Navias, reported. "We have a pump that is alive and well."Later today, flight controllers planned to begin re-activating coolant loop A, clearing the way to restart scientific experiments and other hardware that was shut down when the coolant loop suffered a malfunction Dec. 11.The successful spacewalk also clears the way for Expedition 38 commander Oleg Kotov and Russian flight engineer Sergey Ryazanskiy to carry out a spacewalk of their own on Friday. They plan to venture outside to mount cameras on the hull of the Zvezda command module as part of a commercial venture to beam down high-definition Earth views to subscribers around the world.Today's spacewalk was the 258th by U.S. astronauts, the 176th devoted to station assembly and maintenance since construction began in 1998, the 10th so far this year, the eighth for Mastracchio and the second for Hopkins.One hundred and 14 astronauts and cosmonauts have now spent 1,107 hours and 37 minutes of spacewalk time building and maintaining the International Space Station since construction began in 1998. Mastracchio's total through eight spacewalks now stands at 51 hours and 28 minutes, moving him up to sixth on the list of most experienced spacewalkers. Hopkins total EVA time through two spacewalks stands at 12 hours and 58 minutes.The goal of today's outing was to install a replacement ammonia pump module in coolant loop A, one of two cooling systems used to dissipate the heat generated by the station's electrical systems. A valve in the loop A pump assembly malfunctioned Dec. 11, partially disabling the system and forcing flight controllers to power down non-essential systems.More important, the malfunction left the station one failure away from a much more drastic powerdown should the lone operational coolant loop break down.During a five-hour 28-minute spacewalk Saturday, Mastracchio and Hopkins disconnected the suspect ammonia pump module on the right side of the station's main power truss, pulled it from its slide-in rack in the S1 segment of the truss and mounted it on a nearby storage fixture to complete phase one of the coolant system repair job.Because of an accidental switch throw inside the airlock at the end of the spacewalk, a small amount of water got into the plumbing of Mastracchio's backpack, raising the possibility that potentially damaging ice could form during the second EVA.As a result, Mastracchio assembled a different suit for the second spacewalk while Hopkins used the one he wore Saturday, the same suit that developed a potentially dangerous leak during a July spacewalk.After exhaustive troubleshooting, engineers concluded the leak was caused by contamination that clogged a filter. While the root cause of the contamination has not yet been determined, the astronauts replaced suspect components and both suits performed normally during both coolant repair spacewalks.During their second spacewalk Tuesday, Mastracchio and Hopkins focused on installing the replacement pump module.In spectacular video downlinked from the station, Mastracchio and Hopkins, anchored to the end of the station's robot arm, could be seen unbolting the spare pump module from its storage pallet and pulling it from its insulated enclosure."Looks like you're almost there," Mastracchio radioed as arm-operator Koichi Wakata, working inside the Destiny lab module, slowly pulled Hopkins and the pump assembly away. "You're out of the groove there, Mike, I think you're in charge now of the pump module. ... It's stable, Mike, it looks good, you're doing a great job, it looks beautiful."Hopkins held the tethered pump module in his gloved hands as Wakata slowly moved him inboard from the storage pallet on the S3 truss segment to the pump's install location in the S1 segment.The astronauts then guided the big module into place and drove home bolts to lock it down. They had no trouble hooking up the first two ammonia lines, known as M1 and M2. Another two lines, M3 and M4, were attached to a jumper box Saturday to allow the ammonia in the coolant loop to expand and contract as needed when the station flew into and out of sunlight.The astronauts initially were unable to disconnect the half-inch-wide M4 line from the jumper box. Mastracchio retrieved a tool designed to apply additional force to the quick-disconnect bale holding the mechanism together. The idea was to push the lever far enough over to allow the astronauts to depress a locking button, allowing them to separate the two sides of the fitting.But the stubborn fitting refused to cooperate."One thing we never expected," Mastracchio muttered at one point.After positioning the quick-disconnect tool with varying degrees of force, flight controllers decided to lower the pressure in the line. Right around that point, the astronauts successfully demated the stubborn fitting, but reported "we do have snow coming out."A few moments later, astronaut Douglas Wheelock in mission control asked the spacewalkers if ammonia was still leaking out "or has it dissipated.""Yes. It's about one every second, one little snowflake a second," Mastracchio replied.Asked if their spacesuits had been hit by any ice, Mastracchio said "absolutely," adding a few moments later "they are just completely drowning us now.""Copy, Rick," Wheelock said. "And we have no video, Rick, so we'll just take your continued description.""OK. They're pretty good size particles, much bigger than anything we've ever seen. See that big one going by you, Mike?""I do," Hopkins said."It looks like they're coming inboard of the pump module, all around the pump module, looks like," Mastracchio said. "I can't see it everywhere, where the light is, but they're hitting the wrist cluster of the SSRMS (robot arm), they're enveloping Mike, probably enveloping me, also.""Yes they are," Hopkins said. "Big chunks, big chunks."The ammonia presumably was trapped in the line and expelled when flight controllers sent commands to vent the jumper box. The leak rate diminished a few moments later and the astronauts pressed ahead with work to attach M4 and then M3 to the replacement pump module.The ammonia posed no threat to the spacewalkers, but they had to spend a few extra minutes in vacuum to give any ice crystals that may of stuck to their suits time to dissipate. Decontamination procedures have been required during past spacewalks involving the ammonia coolant system to make sure returning spacewalkers don't introduce any toxic material into the station's air supply.NASA originally held open the possibility of a third spacewalk to complete the coolant system repair work, but with the successful pump installation and activation Tuesday, the station crew now can look forward to a quiet Christmas in orbit before making preparations for the Russian spacewalk Friday.NASA Astronauts Complete Space Station Cooling System Repairs With Second SpacewalkMark Carreau-- Aviation WeekSpacewalking NASA astronauts Rick Mastracchio and Mike Hopkins completed repairs to the six person International Space Station's crippled external thermal control system on Tuesday, wrapping up the complex task in two rather than the three spacewalks originally envisioned.During Tuesday's 7 1/2 hour excursion, the two men installed a new refrigerator-sized pump module for the ammonia thermal control system in an onboard segment of the station's starboard solar power system truss.As they prepared to return to the ISS airlock to end the spacewalk at 2:23 p.m., EST, NASA activated the new module in a brief "bump test," suggesting the new pump and its control valves were electronically functional. The successful re-pressurization of the Loop A thermal control apparatus with nitrogen and a more exhaustive post-repair check out followed on Tuesday night."The new pump (module) is considered fully functional," NASA said in a statement late Tuesday.The measured reactivation of ISS dual Loop A and B cooling was under way Wednesday. The reactivation of electronic systems deactivated after Loop A was degraded by a Dec. 11 flow control valve electrical failure was to follow through the weekend.Unlike the first repair spacewalk on Saturday, Mastracchio and Hopkins had to contend with the possible contamination of their spacesuits from a small amount of frozen ammonia, a toxic substance, that leaked during reconnection of one of four coolant lines to the new pump.Loop A and its Loop B twin circulate ammonia coolant through radiators that extend from the ISS power truss to cool critical electrical systems, including those assigned to life support and scientific research. Scientific investigations were among those activities suspended by the loss of Loop A thermal control two weeks ago."Thank you guys," Mission Control told Mastracchio and Hopkins as they wrapped up their work. "This is the best Christmas ever."The old pump module, which was removed during a spacewalk on Saturday, remains temporarily attached to a fixture on the Mobile Base System -- a rail car that runs along the truss parked close to the worksite. NASA expects to relocate the old 780-pound pump control module to a permanent external storage site during a future spacewalk. The bulky deactivated module can remain at the temporary site until June, according to a weekend thermal analysis by NASA engineers.NASA is hopeful it can be refurbished while in orbit.As on Saturday, neither Hopkins nor Mastracchio experienced a repeat of the worrisome July 16th leak of water that flowed into the helmet of European Space Agency astronaut Luca Parmitano, who was wearing a NASA spacesuit. However, Mastracchio was required to change NASA spacesuits between the Saturday and Tuesday spacewalks after the cooling system sublimator in his personal life support system backpack activated in the ISS airlock following the first excursion and raising concerns of a water intrusion.During Saturday's 5 ½ hour first spacewalk, Hopkins and Mastracchio detached four ammonia coolant lines, five electrical connectors and four hold down bolts to extract the old pump module from its perch on the power truss. The most challenging task was detaching the ammonia lines without a significant leak of the toxic coolant.They reversed those steps on Tuesday, but were slowed by balky attach bolts as well as a spray of frozen ammonia while remating the third of four coolant lines."We do have snow," Mastracchio reported to NASA's Mission Control, a reference to the flaky appearance of the frozen coolant as it emerged from a connection point.Later, the spacewalkers inspected their spacesuits for evidence of frozen ammonia. They reported no obvious signs of contamination.Mission Control, however, asked the two men to carry out a 15 minute airlock ammonia decontamination procedure before rejoining their four station colleagues.The spacewalkers were assisted during both excursions by Japanese astronaut Koichi Wakata, who served as the internal operator of the Canadian robot arm. The 58-foot-long arm moved the spacewalkers and the new pump module around the outside of the station.An electrical problem on Dec. 11 disabled the flow control valve in the older pump module, allowing low temperature ammonia to reach heat exchangers in the station's U.S. segment Harmony and Destiny modules. Those exchangers transfer heat from water cooling lines in the U.S. segment's habitable modules to the external ammonia loop.
The cold ammonia temps could cause the water to freeze, expand and damage plumbing that would allow unwanted ammonia into the ISS living volume.
With Loop A degraded, NASA flight control teams were forced to shutdown non-essential electronics inside the station, including those in the European Columbus and Japanese Kibo science modules. Loop B, took on additional thermal control chores as well so that both loops could continue to dissipate the heat generated by the station's solar arrays, power storage batteries and switching units.
On Friday, Russian ISS cosmonauts Oleg Kotov and Sergey Ryazanskiy are scheduled for a six to seven hour spacewalk to install a pair of external Earth observing cameras and service several experiments. The excursion will represent the 11th this year by ISS crews, the sixth by cosmonauts.Spacewalkers finish crucial space station repairs in time for ChristmasAlan Boyle -- NBC NewsNearly two weeks after a faulty coolant valve crippled the International Space Station, two NASA astronauts took on a rare Christmas Eve spacewalk to get things back to normal.During Tuesday's seven-hour, 30-minute repair operation, spacewalkers Rick Mastracchio and Mike Hopkins installed a refrigerator-sized coolant pump module with an assist from Japanese astronaut Koichi Wakata, who operated the 58-foot-long (18-meter-long) robotic arm from inside the space station.NASA commentator Rob Navias said the new module passed an initial pressure test. "We have a pump that is alive and well," he reported on NASA TV.The only other time NASA conducted a spacewalk on Christmas Eve was during a Hubble repair operation in 1999. The timing lent a holiday spirit to Tuesday's proceedings. "It's like Christmas morning, opening up a little present here," Mastracchio joked as he checked his tools.Two and a half hours into the job, Hopkins stood at the end of the robotic arm and steadied the 780-pound (355-kilogram) pump module as it was swung into position for installation. "Mike Hopkins taking a special sleigh ride on this Christmas Eve," Navias observed.The spacewalk didn't always go as smoothly as Santa's rounds, however: After the astronauts slid the boxy apparatus into place and secured it with bolts, they had some trouble switching the cooling system's fluid lines. They had to tap and pry at one of the interim fluid-line connections to free it up, and in the process they set off a mini-blizzard of toxic ammonia "snowflakes."The snowflakes dissipated, and all the proper connections were eventually made. But the astronauts reported that some of the frozen ammonia got onto their spacesuits. As a result, they had to take some extra time to let the chemicals "bake out" from their suits before ending the spacewalk.Essential roleTuesday's spacewalk followed up on Saturday's operation to remove the faulty pump module. A valve inside that module failed on Dec. 11, forcing one of the station's two ammonia coolant loops to go offline.The cooling system plays an essential role in keeping the onboard electronics from overheating. When the first loop failed, NASA had to shut down non-essential systems and switch other systems over to the second loop, reducing the station's safety margin in the process. If the other loop had failed, that could have forced the six-man crew to abandon the station.A similar pump module switch-out required three difficult spacewalks in 2010, but only two were needed this time around, in part because of the lessons learned three years earlier. The astronauts who were involved in those 2010 spacewalks, Doug Wheelock and Tracy Caldwell Dyson, were on hand at Mission Control in Houston to lend advice.When the repairs were made, Wheelock told the crew, "It's the best Christmas ever.""Merry Christmas to everybody," Hopkins replied. "It took a couple of licks to get 'er done, but we got it."Worries about waterSafety concerns added some extra twists to the past week's repair operation: In July, Italian astronaut Luca Parmitano almost drowned when water from his spacesuit cooling system backed up into his helmet. The crew overhauled the spacesuits, and NASA pronounced them "clean" — but as a precaution, the helmets were equipped with absorbent pads and emergency snorkels.Neither Mastracchio and Hopkins reported any helmet problems on Saturday or on Tuesday.After Saturday's 5.5-hour spacewalk, Mastracchio mistakenly flipped a switch on his suit that may have sent water to a different cooling device known as a sublimator. In a worst-case scenario, that could have caused the device to freeze up during the next spacewalk.As a result, Mastracchio's suit was set aside to dry out, Hopkins' suit was resized to fit Mastracchio, and a backup suit was fitted for Hopkins' use. The switch required an extra day of preparation — which is why the follow-up spacewalk took place on Tuesday instead of Monday, as originally scheduled.Getting back to normalIf further tests confirm that Tuesday's repairs were successful, operations could return to normal over the next few days. NASA also could go ahead with a cargo resupply mission that had to be postponed due to the cooling system problem. The launch of Orbital Sciences' Cygnus cargo capsule is now scheduled for Jan. 7.The station is currently at its maximum capacity of six live-aboard spacefliers. In addition to Mastracchio, Hopkins and Wakata, three Russians round out the crew: Oleg Kotov, Sergey Ryazanskiy and Mikhail Tyurin.Kotov and Ryazanskiy are planning a spacewalk of their own on Friday, to install new equipment on the station's Russian segment.Christmas Eve spacewalk for repair job endsJethro Mullen - CNNWhile many people spent Christmas Eve doing last-minute shopping, two American astronauts had a more challenging matter to attend to Tuesday.In orbit more than 200 miles above Earth, flight engineers Rick Mastracchio and Mike Hopkins embarked on a spacewalk Tuesday morning to repair part of the International Space Station's cooling system.The spacewalk ended at 2:23 p.m. ET Tuesday and lasted 7 hours and 30 minutes, NASA said.More than four hours into the job, the two astronauts had successfully bolted a replacement ammonia pump module into its location and were working to connect lines to allow the ammonia to flow, NASA said in a tweet.There was a slight kink in the work when one of the fluid lines tangled. The astronauts untangled it, but when they did, the line released some ammonia flakes that landed on their space suits.It was not a leak, but some residue, NASA spokesman John Ira Petty said. The ammonia that landed on the spacesuits will require the spacewalkers to air out their suits before going back into the station, but is otherwise not a big deal, he said.The two engineers were carrying out the second in a series of expeditions needed to replace a malfunctioning pump, which circulates ammonia through loops outside the station to keep equipment cool.The pump developed problems December 11 when an internal valve stuck in an incorrect position. The space station's life support system remains up and running, but operations were cut back as a result of the problem, NASA said.It is the second Christmas Eve spacewalk in history, according to NASA.The two astronauts spent about 51/2 hours outside the space station Saturday working to remove the problematic pump.Spacesuit problemMastracchio used a different spacesuit after a small amount of water leaked into the cooling system of the one he wore Saturday.NASA said the issue with the suit, which happened at the end of the spacewalk, was unrelated to a problem experienced in July when water pooled in an Italian astronaut's helmet, causing a spacewalk to be cut short."Both Mastracchio and Hopkins reported dry conditions repeatedly throughout Saturday's activities and the two were never in danger," the agency said.NASA had installed new safeguards, including snorkels inside the spacesuits that would allow astronauts to take breaths if water formed and they had to return to the space station.Tuesday's spacewalk was the 176th to support the space station's assembly and maintenance, according to NASA.The previous Christmas Eve spacewalk took place in 1999, the agency said, when Discovery astronauts Steve Smith and John Grunsfeld spent more than eight hours refitting parts of the Hubble Space Telescope.The others on board the International Space Station at the moment include Russian cosmonauts Mikhail Tyurin, Sergey Ryazanskiy and Oleg Kotov and Japanese astronaut Koichi Wakat.Nasa astronauts repair pump in rare spacewalkBBC NewsTwo US astronauts have successfully repaired a critical cooling system pump at the International Space Station, the US space agency Nasa says.Rick Mastracchio and Mike Hopkins completed a spacewalk of 7.5 hours to replace the faulty ammonia pump.The pump broke down two weeks ago, leaving the US side of the station without half its cooling system.All non-essential equipment had to be switched off and many scientific experiments were halted.Nasa now says all the systems should be back up and running by the weekend."It's the best Christmas ever," Mission Control radioed the astronauts.In reply, Mr Hopkins said: "Merry Christmas to everybody. It took a couple (of) weeks to get her done, but we got it."It was the two astronauts' second spacewalk in three days to replace the pump, which is about the size of a refrigerator.Nasa has said that the station's six-member crew was never in danger.It was only the second Christmas Eve spacewalk in the history of the space programme. The only previous spacewalk on 24 December was in 1999 during a Hubble Space Telescope repair mission.Tuesday's repair mission came on the 45th anniversary of the now iconic Earthrise photograph, taken by the crew of Apollo 8 as they orbited the Moon in 1968.Astronauts successfully replace faulty pump on ISSMonte Morin – Los Angeles TimesNASA astronauts Tuesday successfully replaced a faulty fluid pump in the International Space Station, following two days of work in the open vacuum of space 260 miles above the Earth's surface.The 7 1/2-hour spacewalk was only the second in NASA history to occur on Christmas Eve. The first was in 1999, when astronauts made repairs to the Hubble Space Telescope.Like any DIY home-improvement project, the work involved a glitch or two. The first occurred when a fluid line refused to budge and Astronauts Rick Mastracchio and Michael Hopkins struggled to remove it.When they finally did get it off, tiny flakes of frozen ammonia drifted from the connection, raising concerns that the flakes had landed on the astronauts' spacesuits and might be brought back into the ISS, where they would instantly turn to a corrosive gas.Though the crewmen initially planned to undergo a decontamination procedure known as a "bake-off," that requirement was waived in the final minutes of the mission. Lengthy exposure to the sun during the work probably eliminated the threat, Mission Control in Houston determined."Head to the barn," Mission Control told the astronauts as they entered the space station's airlock just before 11 a.m. PST, after completing the work.Mastracchio and Hopkins had been tasked with replacing a pump in one of the station's two external ammonia cooling loops. The system is responsible for keeping instruments inside and outside the station from overheating.On Saturday, the astronauts worked 5 1/2 hours to disconnect the faulty pump from four ammonia fluid lines and move it to a storage site.Early Tuesday morning, the astronauts maneuvered a new, refrigerator-sized pump into place with the help of a massive robotic arm controlled by Japanese astronaut Koichi Wakata inside the station."Mike Hopkins taking a special sleigh ride on this Christmas Eve," Mission Control commentator Rob Navias said as Hopkins stood on the end of the robotic arm gripping the new pump.The 3-year-old ammonia pump stopped working on Dec. 11 due to a faulty valve, requiring astronauts to halt numerous science experiments until the problem was resolved. The replacement pump is one of three spares on the ISS.The second day of repair work was initially planned for Monday, but the spacewalk was postponed a day due to a potential problem with Mastracchio's spacesuit. Crew members reported that water entered the suit when the astronaut accidentally hit a switch in the space station airlock.The postponement allowed crew members to assemble a second replacement suit for Mastracchio.The recent spacewalks were absent the problems that plagued Italian astronaut Luca Parmitano of the European Space Agency in July. During that walk, Parmitano's helmet began to fill with water when the suit's cooling system backed up and began to leak. The astronaut nearly drowned as blobs of weightless water clung to his head.NASA officials said the problems with the two spacesuits were unrelated, and that the suits had been modified to prevent such episodes in the future. Those modifications included the installation of absorbent pads and breathing snorkels.Repair gives ISS a cool giftSpacewalkers fix faulty system just in time for ChristmasJames Dean -- FLORIDA TODAYSpacewalkers on Tuesday delivered a welcome Christmas gift to the International Space Station, completing repairs that were expected to fully restore the outpost's hobbled cooling system.Astronauts Mike Hopkins and Rick Mastracchio retrieved and installed a spare coolant pump, a refrigerator-sized white box that appeared to lack only a colorful bow to fit the holiday season.Full activation of the new pump module was planned late Tuesday, but it passed a preliminary test during the spacewalk, which lasted seven hours and 30 minutes."Houston, you got yourself a new pump module, congratulations," Hopkins radioed after making the final electrical connection."It's the best Christmas ever, thanks guys," said Doug Wheelock, an astronaut working with the crew from Mission Control, as the spacewalk wrapped up.Today, teams on the ground hoped to start powering up non-critical systems that were shut down two weeks ago, after the failure of a valve that regulated temperatures in one of two coolant loops outside the station.The six-person Expedition 38 crew was never in danger, but the Dec. 11 malfunction left the orbiting research complex vulnerable to more serious breakdowns, a position NASA did not want to remain in long.Hopkins and Mastracchio removed the faulty pump during a five-and-a-half hour spacewalk on Saturday, then installed one of three available spares on Tuesday.It was NASA's second Christmas Eve spacewalk, following one in 1999 to service the Hubble Space Telescope.And the repairs unfolded 45 years after Apollo 8 astronauts beamed the famous "Earthrise" image back from orbit around the moon and read verses from the Book of Genesis."We close with good night, good luck, a Merry Christmas — and God bless all of you, all of you on the good Earth," Frank Borman, the commander of that mission, said then.Tuesday's excursion included some dramatic views of its own, as Hopkins moved the pump while positioned on the end of the station's 58-foot robotic arm, flying against a backdrop of blue oceans and white cloud formations circling 260 miles below."Beautiful view," said Hopkins, who was performing his second spacewalk, to Mastracchio's eighth.The effort's success briefly appeared in doubt as the duo struggled to connect one of four ammonia coolant hoses to the newly installed pump module.In the process, ammonia crystals spurted from the lines, enveloping them in small particles and some larger chunks of potentially dangerous "snow."As a standard precaution, the spacewalkers took time to "bake out" any ammonia that might have stuck to their suits, so they did not track the highly toxic substance back inside the station.The spacewalk was the 176th supporting assembly and maintenance of the 15-year-old ISS, and one more is scheduled this year that is unrelated to the cooling system repairs.Russian cosmonauts Oleg Kotov and Sergey Ryazanskiy plan to head outside Friday morning.Astronauts complete rare Christmas Eve spacewalkMARCIA DUNN -- APCAPE CANAVERAL, Fla. — Space station astronauts repaired a crippled cooling system during a rare Christmas Eve spacewalk Tuesday, braving a "mini blizzard" of noxious ammonia as they popped in a new pump.It was the second spacewalk in four days for U.S. astronauts Rick Mastracchio and Michael Hopkins, and only the second Christmas Eve spacewalk ever.NASA ordered up the spacewalks to revive a critical cooling loop at the International Space Station. All nonessential equipment had to be turned off when the line conked out Dec. 11, and many science experiments halted.With Tuesday's success, the cooling system should be restored and all equipment up and running by this weekend, according to NASA."It's the best Christmas ever," Mission Control radioed as the 7½-hour spacewalk came to a close."Merry Christmas to everybody," replied Hopkins. "It took a couple weeks to get her done, but we got it."Mastracchio and Hopkins removed the faulty ammonia pump during Saturday's spacewalk. On Tuesday, they installed the fresh pump.Standing on the end of the station's main robotic arm, Hopkins clutched the 780-pound, refrigerator-size pump with both hands as he headed toward its installation spot, and then slid it in. An astronaut working inside, Japan's Koichi Wakata, gingerly steered the arm and its precious load."Mike Hopkins taking a special sleigh ride on this Christmas Eve," Mission Control commentator Rob Navias said as the space station soared over the Pacific.It was slow going because of a balky ammonia fluid line that sent frozen flakes of the extremely toxic substance straight at the men — "a mini blizzard," as Mission Control called it. The spacewalkers reported being surrounded by big chunks of the stuff that bounced off equipment and, in all probability, their suits.The ammonia needed to dissipate from their suits before the pair returned inside, to avoid further contamination."Wow," Hopkins sighed after the fourth and final fluid line was hooked to the new pump. The electrical hookups went more smoothly, and six hours into the spacewalk, Hopkins finally called down, "Houston, you've got yourself a new pump module."Christmas references filled the radio waves as the action unfolded 260 miles above the planet."It's like Christmas morning opening up a little present here," Mastracchio said as he checked his toolkit. Later, as he worked to remove the spare pump from its storage shelf, he commented: "Now it really feels like I'm unwrapping a present."Mission Control in Houston was in a festive mood, despite the gravity of the situation. Tabletop Christmas trees, Santa dolls and red Santa caps decorated the desks.NASA's only previous Christmas Eve spacewalk occurred in 1999 during a Hubble Space Telescope repair mission.But NASA's most memorable Christmas Eve was back on Dec. 24, 1968. Apollo 8 astronauts read from Genesis, the first book of the Bible, as they orbited the moon on mankind's first lunar flight.A bad valve in the ammonia pump caused the latest breakdown.Another team of spacewalking astronauts installed that pump just three years ago, and engineers are perplexed as to why it didn't last longer. NASA hopes to salvage it in the years ahead.The 2010 replacement required three spacewalks because of the difficulty in removing pressurized ammonia fluid lines. But this time, the astronauts managed to squeeze everything into two after NASA reduced the pressure and simplified the task.Mission Control successfully activated the pump Tuesday night. The two-line external cooling system uses ammonia to dispel heat generated by on-board equipment; only one loop was disabled by the breakdown.The second spacewalk was supposed to take place Monday but was delayed a day to give Mastracchio time to switch to another suit. He inadvertently hit a water switch in the air lock at the end of Saturday's excursion, and a bit of water encroached on a cooling device in the backpack of his suit, making it unusable.Otherwise, the suits remained dry during both spacewalks. Last July, an astronaut almost drowned when water from his suit's cooling system flooded his helmet. Makeshift snorkels and absorbent pads were added to the suits as a precaution.A Moscow-led spacewalk, meanwhile, is set for Friday. Two Russian crew members will install new cameras and fresh experiments outside.Russia delay Soyuz-2-1v debutNathaniel Downes and Chris Bergin – NASA Spaceflight.comRussia postponed the debut their new Soyuz-2-1v rocket that was set to launch on Wednesday.The secretive launch of the new Soyuz – that does not sport any of the boosters familiar to the other members of the Soyuz family – was set to loft the Aist satellite and two SKRL-756 calibration spheres on Christmas Day from launch pad 43/4 at the Plesetsk Cosmodrome.The Soyuz is one of the best known launch vehicles on the planet, with a rich history that ranges back into the early days of the space program,The new vehicle is a member of the Soyuz-2 family, a direct descendant of the older and wildly successful Soyuz-U family of rockets.Several variants of the Soyuz-2 family include the Soyuz-2-1a, an upgrade of the Soyuz-U with modern digital electronics and revised upper stage functions.Soyuz-2-1b replaced the upper stage with a new unit, powered by an improved avionics suite and more powerful engine.The Soyuz-ST – flown out of Kourou, French Guiana – provided a customized version of the Soyuz-2 for use by the European Space Agency (ESA).For the 2-1v, the program is making a large change, replacing the 55 year old design for the first stage and its boosters. This initiative came after successful inaugural flight of the Soyuz-2-1b in 2008, with final approval granted for what is known as the Soyuz-2-1v program.The Soyuz-2-1v marks an increase in the first stage diameter from 2 meters to 2.7 meters, and replaces the aged RD-108 with a new engine.The vehicle will carry over the control and guidance systems from the Soyuz-2-1b and will interface with the already existing ground support equipment.Per an array of presentations in the L2 Russian Section – L2 LINK – the vehicle stands 44 meters tall on the launch pad.Replacing the legacy R-7 first stage and boosters, the new first stage sports a replacement engine, designated as the 14D15, built by the NK Engines Company.Images of the engine show it is based on the NK-33, from Sergei Korolev's ambitious moon rocket, the N-1.Notably, Orbital's Antares launch vehicle also utilizes engines derived from the NK-33 – the Aerojet-supplied AJ26-62.While the Soyuz-2-1v uses one main engine – with a separate engine for vector and roll control – Orbital's rocket utilizes two AJ-26′s together, in order to handle vector and roll control requirements.This engine's stats include a thrust rating listed at 1,545 KN (Sea Level), 1,720 KN (Vacuum), with a Thrust Specific Impulse of 297.6s (Sea Level), 331.2s (Vacuum), with a thrust range of 55 percent to 100 percent of rating.Documentation also shows another engine on the core, the RD-0110R called the 14D24. The 14D24 handles the vector and roll controls for the first stage.The stats for this engine include a thrust rating listed at 24.28 KN (Sea Level), 27.81 KN (Vacuum), with a Thrust Specific Impulse of 260.5s (Sea Level), 298.3s (Vacuum), while the dry weight of the engine is 425 kg, compared to 1,250 kg for the 14D15.In addition, the new launch vehicle will debut with the new Volga insertion stage. Said to be cheaper than the Fregat stage currently in service, the Volga will cater for orbital insertion to orbits as high as 1700 km.Built to endure up to 24 hours of operation – with multiple restart capability – the Volga is targeted at the largest base of Fregat customers on the Soyuz, those seeking mid to high orbits.This unit has been developed internally by TsSKB, who are aiming to ensure the Volga will be compatible with the entire Soyuz-2 fleet of launch vehicles.The company predicts it could replace the more expensive Fregat on half of missions it is currently used for.The engine details for the Volga Upper Stage have not been disclosed at this time.The most striking element for the Soyuz-2-1v is the removal of the distinctive boosters that are usually seen surrounding the core stage. However, careful examination of the booster reveals that there is still provision to add four boosters to the design as a potential upgrade path for the future.Several concepts relating of this projected upgrade have appeared over the years, but have remained on the drawing board. One such upgrade is called the Soyuz-2-3, which sports boosters using the RD-0155 engine, RD-193 engine or RD-120 engine.The design of these boosters have varied over time, but a model on display in Vienna shows a vehicle with four cylindrical boosters topped with a nose reminiscent of that found on the Energia.Further evolution is noted in the notional Soyuz-3 project, which replaces the Soyuz-2 upper stage with a new unit, based on a Hydrogen-driven – as opposed to Kerosene – Soyuz-2 upper stage, using the new RD-0146 engine co-developed with Pratt & Whitney.The first flight unit of the 1v was completed in 2012 and shipped to the launch site at Plesetsk.The first test stage of the 1v was rolled out on January 6, 2011 from the Zagorsk testing facility in Peresvet Russia, just north of Moscow. It was then used for several engine tests relating to the fuel system, tank pressure testing, etc.The first full-up firing of the complete first stage took place at the Zagorsk facility – which has been home for rocket stage testing since 1949, following the inaugural test of a Russian copy of the German V-2 rocket.The launch of the new rocket has been delayed several times.Little is known about the payloads that are set to ride uphill on this debut launch, other than an Aist satellite will be riding alongside two SKRL-756 calibration spheres.Aist – a prototype spacecraft designed by the Rocket and Space Center and Samara State Aerospace University - will be launched on top of the upper configuration, while the two spheres will be placed on either side, below the Aist spacecraft.The target orbit for Aist is understood to be in a 575 km altitude with a 64.9 degree inclination – similar to the orbit of a previous Aist spacecraft launched by a Soyuz 2-1A earlier this year during the BION-M mission.Rugged Martian Terrain Chewing Up Curiosity Rover's WheelsMike Wall – SPACE.comEngineers are gearing up to perform a check of the Mars rover Curiosity's six wheels, which have accumulated a lot of wear and tear during the robot's 16 months on the Red Planet.In the near future, the mission team plans to drive NASA's 1-ton Curiosity rover r to a smooth patch of ground and photograph its six aluminum wheels using the robot's arm-mounted Mars Hand Lens Imager camera (MAHLI), oficials said."We want to take a full inventory of the condition of the wheels," Curiosity project manager Jim Erickson, of NASA's Jet Propulsion Laboratory in Pasadena, Calif., said in a statement today (Dec. 20)."Dents and holes were anticipated, but the amount of wear appears to have accelerated in the past month or so," Erickson added. "It appears to be correlated with driving over rougher terrain. The wheels can sustain significant damage without impairing the rover's ability to drive. However, we would like to understand the impact that this terrain type has on the wheels, to helpwith planning future drives."
Routes to future destinations may prioritize reducing the time Curiosity spends trundling over sharp rocks and other rough terrain, mission officials added.Engineers also just finished upgrading the rover's software, marking the third such installation peformed since Curiosity touched down inside Mars' huge Gale Crater in August 2012.Among other features, this latest version improves Curiosity's ability to use its robotic arm while on slopes, mission team members said. This skill should come in handy when the rover reaches the base of Mount Sharp, which rises 3.4 miles (5.5 kilometers) into the Martian sky from Gale Crater's center.Mount Sharp has long been Curiosity's main destination. Mission scientists want the rover to climb up through the mountain's foothills, readingthe history of Mars' changing environmental conditions as it goes.
The chief goal of Curiosity's $2.5 billion mission is to determine if Mars has ever been capable of supporting microbial life. Mission scientists have already answered that question in the affirmative, finding that a spot near Curiosity's landing site called Yellowknife Bay was indeed habitable billions of years ago.Curiosity departed Yellowknife Bay for Mount Sharp in July. It should reach the mountain's base around the middle of next year, officials have said.ENDMore detailed space news can be found at:
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