| | JSC TODAY CATEGORIES - Headlines
- Joint Leadership Team Web Poll
- Today -- Give a Little. Help a LOT.
- IT Labs' Annual Project Call Ends TODAY
- Energy/Water Saving Tips in Your Work Areas
- Recent JSC Announcement - Organizations/Social
- Gilruth Drive-Through Gate Closed Dec. 16-20
- Multigenerational Differences at Work
- Money, Parenting and the Holidays
- A Gift For You at Starport
- Shoot and Shop Basketball Camp
- Starport Winter Break Camp - Discount Ends Dec.13 |  |
| Headlines - Joint Leadership Team Web Poll
The vast majority of respondents would rather walk a little further than pay for reserved parking. You would also be watching a replay of "The Miracle on Ice" on your phone during that walk. There goes all of my extra funding for next year. This week is the penultimate poll for 2013. I'm a little stressed about that, and was wondering how much the holiday season stresses you. A whole bunch? Not much? Let me know in question one. I've also always wanted to be able to solve one of life's great mysteries. Which one of the great mysteries would you like to solve in question two? Loch Ness? Bermuda Triangle? Abominable Snowman? Chupacabra your Crop Circle on over to get this week's poll. - Today -- Give a Little. Help a LOT.
Stop by Building 3 today between 10 a.m. and 2 p.m. to chat with representatives from several Combined Federal Campaign (CFC)-eligible charity organizations and see what a difference your gift, large and small, can make in the lives of many. Don't believe a $1 a week gift makes a difference? - 12 elementary school students with trained volunteer tutors to help with reading and math
- 10 children with bilingual beginning-to-read books to build early literacy skills
- Three 30-minute appointments for health assessment and counseling for an individual facing physical, developmental or mental health challenges
- One acre of unprotected tropical rainforest, which assures protection of the natural areas vital to our climate and diverse species
- One hour of expert training for a citizen's group interested in preserving natural areas in their communities
... all for just $52 a year! One-time check or cash donations designated to the charity of your choice will be accepted during the fair. - IT Labs' Annual Project Call Ends TODAY
If you have an Information Technology innovation but need the support to do it, submit your idea by 7 p.m. CST with your 60-second elevator pitch video. Applications will be reviewed by our comprehensive, agencywide review panel, with awards announced Jan. 31. - Energy/Water Saving Tips in Your Work Areas
- Adjust window coverings to reduce direct sunlight in summer and close window coverings at the end of the work day year round. Only raise mini blinds 12 inches from the top. Raising them all the way up can make lowering them difficult. For window covering repair, etc., please submit your request electronically to: jsc-furniture@mail.nasa.gov
- Participate in the Super Flex schedule
- Remove energy-using equipment from your work areas, particularly refrigerators, heaters and printers
- Turn off lights in unoccupied rooms
- Use task lighting in your work areas and coordinate with your building Facility Manager to reduce unnecessary lighting
- Report energy- and water-wasting problems to PAE Work Control or your Facility Manager.
- Recent JSC Announcement
Please visit the JSC Announcements (JSCA) Web page to view the newly posted announcement: 13-041: Communications with Industry Procurement Solicitation for Safety and Mission Assurance Engineering Contract (SMAEC) Archived announcements are also available on the JSCA Web page. Organizations/Social - Gilruth Drive-Through Gate Closed Dec. 16-20
The Gilruth on-site drive-through gate will be closed for construction and replacement of a new gate next week from Dec. 16 to 20. Please use off-site roadways to access the Gilruth Center. We apologize for the inconvenience. - Multigenerational Differences at Work
Demographic trends in the United States have brought us to a unique place and time. Americans are extending their careers and, as a result, we are seeing an unprecedented phenomenon: no fewer than four generations coming together in the workplace. Each generation has its own attitude and style, which leads to frequent misunderstandings among the different generations. Increase your awareness on generational influences, tools for collaborative communication and management of multi-generations differences. Please join Anika Isaac, LPC, LMFT, CEAP, NCC, LCDC, for a presentation on "Multigenerational Differences at Work." If you are unable to attend via ViTS, you may attend by WebEx and telephone (information below). Audio dial-in: 1-888-370-7263, pass code 8811760#. Please remember to mute your telephone while listening to the presentation. - Go here
- Enter your name and email address
- Enter the meeting password: Differences12-12
- Click "Join Now"
- Money, Parenting and the Holidays
Worrying about money is one of the major parenting stressors all year round, but it deals a double whammy during the holidays. The increased level of advertising to children and adults for all those shiny objects combines with memories of better Christmases in the past. The temptation is huge to ignore your present reality and just put everything on a credit card ... and worry about it later. Despite the temptations of holiday spending, come learn what actions to take to keep your financial situation from getting worse or putting it off until January. Discover the importance of changing how you look at money and the lessons you can teach your children about money and values during the holiday season. Please join Anika Isaac, MS, LPC, LMFT, NCC, CEAP, LCDC, on Dec. 17 from noon to 1 p.m. in the Building 30 Auditorium for a presentation on "Money, Parenting and the Holidays." - A Gift For You at Starport
It's the holidays, and Starport has a gift for you! Just spend $100 in merchandise and you will get a free Astronaut Nesting Doll; $75 for a NASA umbrella; or $50 to get a free Rockets picture frame. Purchase a Wings In Orbit book and get a free Fisher Space Pen. And, if you spend $50 in toys, you will get a free Legends of Space Collector Series Toy. Happy holidays to our valued customers! - Shoot and Shop Basketball Camp
Shoot-and-shop campers will enjoy a fun-filled day of hoops with basketball coach Tim Glover while mom and dad use this time to finish all of their holiday shopping! - Starport Winter Break Camp - Discount Ends Dec.13
Starport Winter Break Camp is almost here! If you're looking for a fun, convenient and familiar place for your children to go for the school break, look no further. NASA Starport camps at the Gilruth Center are the perfect place. We plan to keep your children active and entertained with games, crafts, sports and all types of fun activities. Dates: Dec. 23, 26, 27, 30| Jan. 2, 3, 6 Time: 7:30 a.m. to 5:30 p.m. Ages: 6 to 12 Discounted cost: $160 all days| $75 per week (three days)| $35 per day Discount ends Dec. 13, so HURRY! Registration is now open at the Gilruth Center. | |
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| JSC Today is compiled periodically as a service to JSC employees on an as-submitted basis. Any JSC organization or employee may submit articles. Disclaimer: Accuracy and content of these notes are the responsibility of the submitters. |
NASA and Human Spaceflight News
Thursday – December 12, 2013
International Space Station:
Karen Nyberg's Twitter audience reached 80,000 plus before landing and was extensively covered by media – see examples here: https://twitter.com/AstroKarenN
HEADLINES AND LEADS
Space station suffers cooling problem; crew safe
NASA engineers determining whether problem with ammonia flow-control valve may require space walk to fix.
Michael Winter – USA Today
In a situation described as urgent but not an emergency, NASA engineers worked Wednesday to determine what caused one of the International Space Station's two cooling systems to shut down.
Houston has a problem with International Space Station; may require spacewalk
Amina Khan – Los Angeles Times
A cooling system failure aboard the International Space Station may require a spacewalk, NASA officials said Wednesday. NASA: Cooling pump on space station shuts down
Seth Borenstein – AP
NASA said Wednesday it was looking into a problem with a malfunctioning cooling pump on the International Space Station, but there was no immediate danger to the six crewmen on board.
Engineers troubleshoot station cooling problem
William Harwood – CBS News
A valve in a coolant system pump module aboard the International Space Station apparently malfunctioned Wednesday, triggering cooling problems in one external ammonia loop and prompting flight controllers to power down non-essential equipment in the forward part of the lab complex, including some of the station's research gear.
With TDRS-L Arrival, NASA's Next Tracking and Data Relay Satellite Begins Final Preparations for January Launch
Ben Evans – AmericaSpace
NASA's 12th Tracking and Data Relay Satellite (TDRS) will shortly begin final processing at the Kennedy Space Center, following its delivery last week to Florida aboard a U.S. Air Force C-17 transport aircraft. Scheduled for launch atop an Atlas V booster from Cape Canaveral Air Force Station in late January 2014, the TDRS-L payload—which will be the 11th member of the satellite family to actually reach orbit, following the loss of TDRS-B in the Challenger tragedy—has been unpacked and inspected to ensure that it sustained no damage during its journey from Boeing's Space and Intelligence Systems facility in El Segundo, Calif. JSC to get another new representative as Stockman aims for the Senate
Jeff Foust – Space Politics
Rep. Steve Stockman (R-TX), whose district includes NASA's Johnson Space Center, surprised many late Monday when he announced he would challenge incumbent Sen. John Cornyn (R-TX) in next year's Republican primary.
Orbital Mates Cygnus to Rocket Ahead of First Contracted Cargo Launch
Dan Leone – Space News
Orbital Sciences Corp. mated its Cygnus space capsule to its Antares rocket in preparation for the first of eight planned cargo delivery missions to the international space station through 2016.
Curiosity rover delivers key pieces of Martian puzzle with recent findings
Leonidas Papadopolous – Spaceflight Insider
A team of scientists working on the Mars Science Laboratory (MSL) rover Curiosity mission, have announced their latest findings of their studies of Yellowknife Bay, the area that the Curiosity rover is currently investigating on Mars. These include the first-ever age measurements of rock formations on the surface of another world. The new findings were presented during the first day of the 2013 Fall meeting of the American Geophysical Union or 'AGU', on December 9 in San Francisco, California.
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COMPLETE STORIES
Space station suffers cooling problem; crew safe
NASA engineers determining whether problem with ammonia flow-control valve may require space walk to fix.
Michael Winter – USA Today
In a situation described as urgent but not an emergency, NASA engineers worked Wednesday to determine what caused one of the International Space Station's two cooling systems to shut down.
Cooling functions were rerouted to the working system after a flow-control valve apparently failed in a loop carrying ammonia along the outside of the station, making it too cold, said NASA Public Affairs Officer Brandi Dean. All life-support and other critical systems were protected and working normally.
"The crew's in no danger at all," she said.
Some non-critical systems were shut down, but none of the science being conducted aboard the station was affected, she said.
Engineers are evaluating whether the problem is hardware- or software-related and "will take all the time necessary" before deciding whether a spacewalk is required to fix it, Dean said.
"It might just require a software upgrade," she said.
In August 2010, astronauts made three spacewalks to repair a broken ammonia coolant pump.
Wednesday, the six astronauts and cosmonauts of Expedition 38 spent the day preparing for upgrades and training for the capture of the commercial cargo craft Cygnus with the station's robotic arm Dec. 21.
The probe, made by Orbital Sciences, will carry several experiments, including one to help make spacecraft more fireproof.
Houston has a problem with International Space Station; may require spacewalk
Amina Khan – Los Angeles Times
A cooling system failure aboard the International Space Station may require a spacewalk, NASA officials said Wednesday. One of two ammonia cooling loops on the station's exterior shut down Wednesday morning, NASA spokeswoman Brandi Dean said.
"You need the cooling in space because heat doesn't dissipate like it does on the ground," she said.
Authorities think that an excess of ammonia triggered a safeguard to shut the loop down.
[Update, 9:05 p.m. Dec. 11: NASA's Johnson Space Center used Twitter to update followers on the situation.
"The pump module on one of #ISS two external cooling loops automatically shut down today when it got too cold," the center tweeted this afternoon.
"The pump was brought back online, but they think a valve may not be working correctly inside it."]
The main modules affected are the Japanese laboratory, the European laboratory and their connecting node, Harmony, Dean said. Some of those systems have been moved to the other cooling loop, and non-critical systems have been shut down.
"There's no danger to the crew at all, all the science is running just fine, all the freezers that hold the scientific samples — it's just a matter of us taking the time to figure out how to get the first loop back up and running at capacity," Dean said.
Flight controllers at NASA's Johnson Space Center in Houston are exploring whether the issue is hardware or software. There are no immediate plans for a spacewalk, but if any parts need replacing, it may become necessary to send an astronaut out to replace the part with spare systems carried on board.
"The crew is safe and preparing to begin a normal sleep shift while experts on the ground collect more data and consider what troubleshooting activities may be necessary," NASA spokesman Josh Byerly said in an email.
The space station experienced an unprecedented scare in July when Italian spacewalker Luca Parmitano came dangerously close to drowning in space. The European Space Agency astronaut managed to find his way back to the station door as his helmet began filling with water.
"You can imagine, you're in a fishbowl. So go stick your head in a fishbowl and try to walk around – that's not anything you take lightly," NASA flight director David Korth said at the time.
In a strange parallel, the malfunction in Parmitano's suit was also linked to a cooling loop.
NASA: Cooling pump on space station shuts down
Seth Borenstein – AP
NASA said Wednesday it was looking into a problem with a malfunctioning cooling pump on the International Space Station, but there was no immediate danger to the six crewmen on board.
A valve on a pump on one of the station's two external cooling loops shut down because it was too cool Wednesday afternoon, NASA spokesman Bob Jacobs said. He said that at no time was the crew at risk. But some non-critical equipment of the massive orbital outpost were powered down.
"It could be a serious problem, but it's not an emergency," Johnson Space Center spokesman Kelly Humphries said.
Engineers suspect a valve inside the pump was faulty and ground controllers moved electrical power supplies to the other cooling loop, Jacobs said. These loops circulate ammonia outside the station to keep equipment inside and outside cool.
"The station wasn't ever in any danger," Jacobs said.
Jacobs said the crew of two American astronauts, three Russian cosmonauts and a Japanese astronaut were preparing to go to bed as normal, while engineers on the ground tried to troubleshoot the problem. The faulty pump and cooling loop did start up again, he said.
Humphries said it was too early to speculate whether a spacewalk would be needed to fix the problem.
The station commander is cosmonaut Oleg Kotov. Americans Rick Mastracchio and Michael Hopkins, Russians Mikhail Tyurin and Sergey Ryazanaskiy, and Japanese astronaut Koichi Wakata are aboard. The orbital outpost, the size of a football field and weighing nearly 1 million pounds, has been in orbit more than 220 miles above Earth since 1998.
Engineers troubleshoot station cooling problem
William Harwood – CBS News
A valve in a coolant system pump module aboard the International Space Station apparently malfunctioned Wednesday, triggering cooling problems in one external ammonia loop and prompting flight controllers to power down non-essential equipment in the forward part of the lab complex, including some of the station's research gear.
The lab's six-member crew was not in any danger, NASA officials said, following a near-normal schedule while engineers on the ground "collect more data and consider what troubleshooting activities may be necessary.
In the meantime, the heat generated by the station's myriad electrical systems is being dissipated by ammonia circulating in coolant Loop B. Coolant Loop A, hobbled by the suspect flow control valve, remained in operation Wednesday evening, but it could not be used for heat rejection.
Some equipment in the forward Harmony module, known as Node 2, and two lab modules that are attached to it -- the European Space Agency's Columbus laboratory and Japan's Kibo module -- could not be fully cooled by loop B alone and some of those systems had to be powered down.
"The ETCS (External Thermal Control System) Loop A is still running, but the flow control valve doesn't appear to be positioning properly," a flight controller radioed the crew earlier Wednesday. "So the Loop A is very cold. We're not expecting it to get warm enough for us to be able to reintegrate for heat rejection."
She said Loop A would be kept in operation as long as possible to carry out "graceful shutdowns of our science equipment. Once the loop shutdown is complete, half of Node 2, half of JEM (Japanese Experiment Module) and half of Columbus will be powered down. But you'll keep half of each module and that is why the crew quarters are not affected."
"Meanwhile, all the thermal loops have been shifted to Loop B, which is struggling to keep up. So we're going to be looking at some additional power downs in other modules to make sure that the highest priority loads get adequate cooling."
It is not yet clear if the apparent problem with the flow control valve is the result of a hardware issue or the software that controls it. If it is software related, a NASA official said, engineers likely will come up with a work-around. If the hardware is at fault, a spacewalk could be required at some point to install a replacement.
The pump module in question was installed during three spacewalks in 2010 after an earlier failure that disabled that loop completely.
In the meantime, NASA and Orbital Sciences Corp. are pressing ahead with plans to launch an unmanned Cygnus cargo ship Dec. 18, Orbital's first operational station resupply mission. Berthing at Harmony's Earth-facing port is expected Dec. 21, assuming no major disruptions because of the coolant system issue.
The space station uses ammonia circulating through a complex system of heat exchangers, plumbing and radiators to dissipate the heat generated by the lab's myriad electrical systems. Flight controllers can use excess capacity in one loop to cool components in the other, but not all systems can remain powered with a single operational coolant loop.
Given the lost redundancy, flight controllers and engineers want to come up with repair options as quickly as possible. Among the systems affected by the powerdown were specific smoke detectors in the forward modules, along with some caution and warning displays, but backup systems remained available.
"Earlier today, the pump module on one of the space station's two external cooling loops automatically shut down when it reached pre-set temperature limits," NASA said in a statement. "These loops circulate ammonia outside the station to keep both internal and external equipment cool.
"The flight control teams worked to get the cooling loop back up and running, and they suspect a flow control valve actually inside the pump itself might not be functioning correctly. At no time was the crew or the station itself in any danger, but the ground teams did work to move certain electrical systems over to the second loop.
"Some non-critical systems have been powered down inside the Harmony node, the Kibo laboratory and the Columbus laboratory while the teams work to figure out what caused the valve to not function correctly and how to fix it. The crew is safe and preparing to begin a normal sleep shift while experts on the ground collect more data and consider what troubleshooting activities may be necessary."
With TDRS-L Arrival, NASA's Next Tracking and Data Relay Satellite Begins Final Preparations for January Launch
Ben Evans – AmericaSpace
NASA's 12th Tracking and Data Relay Satellite (TDRS) will shortly begin final processing at the Kennedy Space Center, following its delivery last week to Florida aboard a U.S. Air Force C-17 transport aircraft. Scheduled for launch atop an Atlas V booster from Cape Canaveral Air Force Station in late January 2014, the TDRS-L payload—which will be the 11th member of the satellite family to actually reach orbit, following the loss of TDRS-B in the Challenger tragedy—has been unpacked and inspected to ensure that it sustained no damage during its journey from Boeing's Space and Intelligence Systems facility in El Segundo, Calif. The satellite is the second in a series of three members of the new "third generation" of TDRS, the inaugural contracts for which were signed between NASA and Boeing in December 2007. Under the terms of that agreement, the aerospace giant built TDRS-K—launched in January 2013—and TDRS-L, at a cost of $695 million, in order to "ensure vital operational continuity" of an on-orbit network of communications and data-relay assets which presently support dozens of spacecraft, including the International Space Station and the Hubble Space Telescope. "The launch of TDRS-L ensures continuity of services for the many missions that rely on the system every day," said Jeffrey Gramling, TDRS project manager at NASA's Goddard Space Flight Center in Greenbelt, Md. The NASA-Boeing agreement is expandable to $1.2 billion, if all options are exercised, and this indeed seemed to be the case when the space agency ordered a third satellite, TDRS-M, in November 2011. Current plans anticipate its launch in December 2015. All three satellites are designed for 15-year operational lifespans, which enables continuity until the middle or even the end of the next decade.
Emplacement of this third generation of satellites coincides broadly with the retirement of the first generation, designated "A" through "G," all of which were launched by the shuttle in the 1980s and 1990s. Of this first generation, one (TDRS-B) was lost in the Challenger disaster, whilst two others (TDRS-A and D) have already been shut down. The others are expected to follow in the near future. A second generation of three satellites—TDRS-H, -I, and -J—were launched aboard expendable rockets between June 2000 and December 2002 and remain fully functional, despite having endured a handful of technical troubles.
With last January's successful launch of TDRS-K, a hiatus of more than a decade since the last satellite was closed. The new third generation is visually quite distinct from its cousins of the first generation. It is based upon Boeing's 601 spacecraft bus, first introduced more than two decades ago, but heavily upgraded over the years, and can support multiple payloads and objectives, including direct TV broadcasts and the needs of private businesses and mobile communications users. The size and output of its communications payload has also expanded, and it is capable of housing up to 60 transponders and producing 10,000 watts of power.
As well as enabling all navigation, power, propulsion, and command capabilities, the bus has twin solar arrays—each measuring 15 feet (4.5 meters) in diameter—for use whilst in direct sunlight and battery packs for use whilst in the Earth's shadow. Its "spring-back" antennas are designed with flexible membrane reflectors, which fold up for launch and spring back into their original, "cupped" circular shape after orbital insertion. The communications hardware consists of microwave equipment, a pair of gimbaled antennas, and a phased-array antenna for forward, return, and tracking services. In addition to operating at S-band and Ku-band frequencies, the second- and third-generation TDRS provide improved overall service and substantially higher bandwidth through the Ka-band.
In March 2009, Boeing selected United Launch Alliance's 19-story Atlas V as its vehicle of choice to deliver the third-generation satellites into orbit. Like its predecessor, TDRS-L will ride an Atlas in the "401″ configuration, with a 13-foot (4-meter) payload fairing, no strap-on rocket boosters, and a single-engine Centaur upper stage. Liftoff from Space Launch Complex (SLC)-41 from Cape Canaveral Air Force Station is tentatively scheduled for 23 January 2014. As the 12th satellite in NASA's fleet, TDRS-L will continue a proud heritage of providing near-continuous tracking, voice, and data communications relay services between ground stations and more than 20 discrete users, simultaneously, including the Hubble Space Telescope and the International Space Station. Yet TDRS arose in the post-Apollo era at one of the most uncertain times for the U.S. human space program, and even its long-awaited maiden launch in April 1983 hung for a time under the shadow of abject failure.
The concept was born in the early 1970s as one of the recommendations of a study group led by Don Hearth, then-deputy director of NASA's Langley Research Center in Hampton, Va., which charted possible post-Apollo roadmaps for America's future in space. The group, which included astronaut Joe Allen on its panel, felt that a system of tracking and relay satellites placed into 22,000-mile (35,000-km) geosynchronous orbits by the shuttle and operated from a single ground terminal at White Sands, N.M., would provide near-continuous voice and data traffic and eliminate the older generation of ships and costly ground stations. In fact, as well as supporting low-orbiting missions, it could relay data from satellites up to 3,000 miles (4,800 km) above Earth's surface. Since the dawn of human space flight, astronauts had been out of contact with Mission Control for up to 80 percent of every orbit; furthermore, satellites had to tape record data and transmit it when they came within range of a tracking ship or ground station. As the shuttle effort gained momentum in the mid-1970s, it was envisaged that two TDRS relays would provide astronauts with space-to-ground voice and data links for between 85–98 percent of each orbit.
TDRS was no miracle worker. In its original incarnation it could not process or adjust communications traffic in either direction. Rather, it operated as a "bent pipe" repeater, relaying signals and data between its Earth-circling users and the highly automated ground terminal. Signals processing, therefore, occurred on the ground, and the satellite's sophistication was devoted to its very high throughput. Located in the inhospitable New Mexico desert, White Sands provided a clear line of sight with the satellites, and its limited amount of annual rainfall meant that weather conditions would not interfere with uplink or downlink capabilities.
It was envisaged that a pair of TDRSs—one stationed over the equator, just off the northeastern corner of Brazil, known as "TDRS-East," and a second over the central Pacific Ocean, near the Phoenix Islands, known as "TDRS-West"—would fill this urgent communications and tracking need. TDRS-A was launched in April 1983, but was almost lost when its Boeing-built Inertial Upper Stage (IUS) booster failed to insert it into its proper orbit. Only by using the satellite's own hydrazine thrusters were controllers able to gradually maneuver it into its final location, although the result was that its operational lifetime was shortened. Ongoing problems with the IUS meant that it was almost three years before the second satellite, TDRS-B, could be launched … and that was the primary payload aboard the ill-fated Challenger on 28 January 1986.
Two more TDRS satellites (C and D) were launched in September 1988 and March 1989, the former replacing the doddery TDRS-A in the west (slightly south of Hawaii) and the latter taking up position in the east, near Brazil. Unfortunately, TDRS-C also succumbed to anomalies which affected its Ku-band relay capability. A fourth satellite, TDRS-E, was launched in August 1991 and positioned at 175 degrees West longitude to become the primary provider of communications services over the Pacific from October 1991. TDRS-A and TDRS-C, meanwhile, were relegated to the status of on-orbit "spares."
This left only TDRS-D and TDRS-E in fully-operational status … which meant that no spare existed to support them in the event of problems. The successful arrivals of TDRS-F in January 1993 and TDRS-G in July 1995 filled this backup capability. This enabled the network to be rearranged to include two fully-operational satellites in the East and West spots, plus the fully-functional TDRS-A as a spare and the partially-functional TDRS-C designated to support NASA's Compton Gamma Ray Observatory.
A few months before the launch of the final first-generation TDRS, in February 1995, NASA's Goddard Space Flight Center chose Boeing to build three second-generation satellites under a contract valued at $481.6 million. Based upon the 601 "bus," the new satellites were intended to augment the Ku-band and S-band capabilities of the first generation with the higher-bandwidth Ka-band. The ground stations at White Sands were modified to accept the new satellites. TDRS-H was launched atop an Atlas booster in June 2000, followed by TDRS-I in March 2002 and TDRS-J the following December. Although TDRS-H suffered problems with its multi-access antenna and TDRS-I lost pressure in one of its four fuel tanks shortly after launch, the second generation has supported International Space Station and other operational assets for more than a decade.
On 4 April 2013, NASA marked the 30th anniversary of the TDRS-A launch. It has been a long and rocky road for a network which was born with such promise, but very soon fell on hard times, yet matured to shine throughout the heyday of the shuttle era and today's International Space Station. It has provided the data-relay capability for the astonishing scientific returns of the Hubble Space Telescope … and even the doddery first satellite has contributed to more down-to-earth achievements. In 1998, NASA allowed scientists at the Amundsen-Scott base in Antarctica to employ TDRS-A as a relay for research data, and it supported a medical emergency at McMurdo Station, allowing scientists to conduct a telemedicine conference with doctors in the U.S. Several of the first-generation satellites are now out of service.
TDRS-A—"the queen of the fleet," according to NASA-Goddard's Space Network Project Manager Roger Flaherty—was deactivated in October 2009, followed by TDRS-D in November 2011. The remaining first-generation satellites (C, E, F, and G) are expected to be retired by 2015. And by the end of that year, it is expected that the entire third-generation will be complete, with TDRS-K, L, and M inserted into geosynchronous orbit. These satellites are immeasurably more powerful than their predecessors, but, like them, they will enable TDRS to evolve through the middle of the next decade as the United States' primary tracking and data-relay service provider for its key human-exploration programs and scientific endeavors.
JSC to get another new representative as Stockman aims for the Senate
Jeff Foust – Space Politics
Rep. Steve Stockman (R-TX), whose district includes NASA's Johnson Space Center, surprised many late Monday when he announced he would challenge incumbent Sen. John Cornyn (R-TX) in next year's Republican primary. Stockman is considered a long shot to unseat Cornyn—he has just $32,000 in the bank for his campaign, versus $7 million for Cornyn—but his decision does give Cornyn more serious, and more conservative, competition than previously expected.
The decision also means that Stockman won't be running for reelection for his House seat. Stockman, in his brief time back in Washington (he served a term in Congress in the mid-1990s) he's served on the House Science Committee and been active on space issues, but has been better known—or, perhaps, infamous—for controversial positions, such as calling for the President's impeachment. Roll Call reports five Republicans have filed to run for Stockman's seat, including Chuck Meyer, who advocated for "Space Bonds" to fund NASA's human spaceflight program during his unsuccessful 2012 campaign for the seat. Thanks to election outcomes and redistricting, JSC has been represented in recent years by Tom DeLay, Nick Lampson, Pete Olson, and, currently, Steve Stockman; by January 2015, another person will have that distinction.
Orbital Mates Cygnus to Rocket Ahead of First Contracted Cargo Launch
Dan Leone – Space News
Orbital Sciences Corp. mated its Cygnus space capsule to its Antares rocket in preparation for the first of eight planned cargo delivery missions to the international space station through 2016.
The scheduled Dec. 18 launch, from a state-owned launch pad at NASA's Wallops Island Flight Faculty on Wallops Island, Va., will be the third for Antares and the second for Cygnus, which delivered its first cache of cargo to the station in a Commercial Orbital Transportation Services (COTS) demonstration mission that wrapped up in October.
Dulles, Va.-based Orbital, like fellow NASA cargo hauler Space Exploration Technologies Corp. (SpaceX), developed its logistics hardware in part with COTS funding and with advances on the Commercial Resupply Services contact it got from NASA in 2008. Orbital's contact is worth $1.8 million. SpaceX's 12-flight deal is worth $1.6 million.
NASA advanced the companies only a portion of the fee owed for each flight. The remainder of the fee can be collected only after a successful mission.
Curiosity rover delivers key pieces of Martian puzzle with recent findings
Leonidas Papadopolous – Spaceflight Insider
A team of scientists working on the Mars Science Laboratory (MSL) rover Curiosity mission, have announced their latest findings of their studies of Yellowknife Bay, the area that the Curiosity rover is currently investigating on Mars. These include the first-ever age measurements of rock formations on the surface of another world. The new findings were presented during the first day of the 2013 Fall meeting of the American Geophysical Union or 'AGU', on December 9 in San Francisco, California.
Even before the rover had arrived on Mars on August 5, 2012, the planetary science community knew that following a succesful landing, the mission would provide crucial data concerning the habitability of the Red Planet. The robotic explorer didn't fail to deliver. After Entry, Descent and Landing (EDL), Curiosity set out to begin its 2-year primary mission of characterising possible past habitable environments around its landing site, inside Gale crater. During its first months on Mars, Curiosity had already achieved this goal, consistently revolutionizing our view of the Red Planet along the way. The rover kept delivering data by discovering evidence of past flowing streams of water, making the first-ever radiation measurements on the Martian surface, drilling on rocks and zapping them with the laser on its Chemistry & Camera (or 'ChemCam') instrument, to measure their chemical composition. Now, Curiosity completed another historic first, by making the first-ever age measurement of a rock, in-situ on the surface of another planet.
Age Determination process
The age measurement results come from a study led by Kenneth Farley, a participating scientist on the MSL mission. The measurements were actually two-fold. The first, concerned the formation age of minerals inside a rock called "Cumberland" and the second concerned the amount of time the rock outcrops on Yellowknife Bay have been exposed to the surface. Cumberland was drilled by Curiosity in during May 2013. The rover then took samples of the resulting powdered rock and inserted them into its Sample Analysis at Mars, or SAM instrument, to investigate the rock's chemical and isotopic composition. The results showed that the samples were somewhat rich in potassium-40, an isotope of potassium that is known to decay into argon-40, with a half-life of 1.2 billion years. Since argon is a noble gas, it doesn't chemically interact with other elements. So, any argon present in the samples, could only be the result of potassium decay. Knowing the rate of potassium to argon decay and the amount of argon in the samples, Falray's team used potassium-argon radiometric dating, a method that is commonly applied on Earth, but had not been used in space before. Radiometric dating came up with an age of approximately 4.2 million years, give or take 400 million.
"The age is not surprising, but what is surprising is that this method worked using measurements performed on Mars," said Farley. "When you're confirming a new methodology, you don't want the first result to be something unexpected. Our understanding of the antiquity of the Martian surface seems to be right." Scientists were pleased to find that the estimate to come out of the radiometric dating method, was also in complete agreement with the estimate given by the crater-counting method previously used to calculate the overall age of the rocks. "This is important, because first of all, it validates the crater-counting models that were used to estimate these ages. This is an absolutely critical part of establishing Mars' history – to have an age determination of crater-counting, and the radiometric method actually confirms for the first time, that these models are valid," he added during his presentation at the recent AGU meeting.
The other important finding unveiled at the meeting, was the surface exposure age of the wider Yellowknife Bay area, where both of Curiosity's drilling targets, the 'Cumberland' and 'John Klein' rocks lay. By carefully studying the geomorphology of Yellowknife Bay, scientists came to the conclusion that the landscape is constantly reshaped by wind erosion. In essence, Mars' surface is sand-blasted by wind, constantly exposing previously underground layers of rock to the surface. Mars also doesn't have a global magnetic field like Earth, so it is constantly bathed in lethal galactic cosmic rays, and ultraviolet radiation coming from the Sun. All this radiation penetrates to a depth of 3 meters below the surface, producing isotopes of various noble gases after colliding with the molecules on the ground and rocks. By measuring the amount of these isotopes inside Cumberland, and by knowing the half-life of their radioactive decay, scientists can estimate how long the rocks at Yellowknife Bay have been at, or within 3 meters from the surface. The results was somewhat surprising to scientists.
"The age that we obtained with all three of the different isotopes that we've used, is about 80 million years," noted Farley. Considering the age of 4.2 billion years of the Cumberland rock itself, it turns out that it was only exposed at the surface in very recent geologic times.
Importance of surface exposure age for habitability
These age determination measurements are very important to the search for organic molecules on Mars as well.
While Curiosity examined the powdered rock samples from Cumberland with its SAM instrument, it detected an abundance of chlorine oxides, like hydrogen chloride (HCl) and perchlorate (ClO4− ). The presence of such oxi-chlorinated compounds on the Cumberland samples was to be expected, since the soil on the surface of Mars had been found to be rich in perchlorate, by NASA's Phoenix mission in 2008. But the scientists detected strong signs of carbon and nitrogen as well, in the form of chemical compounds like carbon dioxide (CO2) and nitric oxide (NO) respectively.
Scientists at first thought that the presence of carbon and nitrogen, was a result of its delivery from Earth inside the SAM instrument. Yet, these two compounds were detected in far larger quantities than those believed to have been carried from Earth, making scientists confident that most of the carbon and nitrogen that was detected, was of Martian origin. That doesn't necessarily mean that something was alive inside the Cumberland samples, but it shows that the rock outcrops of Yellowknife Bay could easily preserve organic compounds.
This conclusion was reinforced by independent studies, made by David Vaniman of the Planetary Science Institute in Tucson, Ariz. And Scott McLennan of Stony Brook University in Stony Brook, N.Y. by examining the clay minerals found inside the Yellowknife Bay rocks. The breakthrough discovery of clay minerals had come in 2012, from Curiosity's first rock drill on Mars, on a neighboring rock called 'John Klein'. Clay minerals are known to be formed in the presence of water, and their abundance at Yellowknife Bay hinted at a past wet and habitable environment, conducive to life. The important discovery from the new studies, is that those minerals were formed in-situ inside the rocks on Yellowknife Bay, after the latter had been deposited there from the rim of Gale Crater, carried by flowing water. This in-situ formation means that habitable environments were present in broader areas on Mars and persisting for much more time than previously thought, maybe more than millions to tens of millions of years.
Even if life has never flourished on Mars, clay minerals are very good agents for the preservation of organic compounds inside rocks, deposited either by meteorites, or by other geological processes. But the surface exposure of rocks, would be a fatal threat for any organics, which would be destroyed by galactic cosmic rays and solar radiation, over a period of hundreds of millions of years. Yet, the discovery that the Cumberland rock has been exposed to the surface for approximately only 80 million years, makes scientists feel confident that enough organics could still be present, for Curiosity to detect. This surface age exposure measurement, gives a baseline to scientists for determining the best places to look for organic compounds, from calculating the surface exposure of rocks.
Radiation exposure measurements and importance on future human missions
One of the instruments onboard Curiosity, is RAD, short for Radiation Assessment Detector. The instrument was turned on even before Curiosity's arrival on Mars, measuring the levels of cosmic and solar radiation in interplanetary space, and after Curiosity's landing on the surface of Mars.
One of the findings that the scientists unveiled at the AGU meeting, were the radiation measurements on the surface of Mars made by RAD, during the first 300 Sols after Curiosity's landing. What the results showed, was that the Martian surface was dominated by the presence of galactic radiation only, with just one solar particle event being recorded. In addition, the recorded levels of galactic radiation on the surface varied significantly, showcasing daily and seasonal variations. Even though the Sun is currently at its Solar maximum, this maximum is amongst the weakest of the past 60 years, thus having a minimal effect on the radiation environment on Mars that RAD has recorded.
More important to the prospect of future human exploration of Mars, Curiosity's results helped scientists to calculate the total radiation exposure an astronaut would get from a turnaround trip there. It turns out that the total radiation exposure an astronaut would get during a 6-month transit to Mars, would be in the range of 650-700 mSv. This happens to be the same radiation exposure from a 500-day stay on the surface of Mars. That's not surprising, considering that the Martian surface is better shielded from radiation than interplanetary space. These levels are still a bit higher than NASA's currently accepted limits. It is calculated that 1000 mSv of radiation would increase a person's risk of getting cancer, by 5 percent. The space agency's current limit for astronauts on the International Space Station, is 3 percent. For comparison, the average radiation dose for a 6-month stay on the ISS, is 75-90 mSv.
"Our measurements provide crucial information for human missions to Mars," says Don Hassler of Southwest Research Institute in Boulder, Colo. and principal investigator for Curiosity's RAD instrument. "We're continuing to monitor the radiation environment and seeing the effects of major solar storms on the surface at different times in the solar cycle, will give additional important data. Our measurements also tie into Curiosity's investigations about habitability. The radiation sources that are concerns for human health also affect microbial survival as well as preservation of organic chemicals."
The fascinating discoveries that were presented in the recent AGU meeting, not only helped to expand our knowledge and understanding of the Martian environment, but proved to be a turning point in Curiosity's mission as well.
As John Grotzinger, project scientist for the Curiosity rover, noted:
"Really what we're doing in the mission, is turning the corner from a mission which is dedicated to the search for habitable environments, to a mission that is now dedicated to a search for that subset of habitable environments which also preserves organic carbon. And that's the step we need to take, as we explore for evidence of life on Mars."
Yet, all the results which have come from Curiosity's first 16 months on Mars, are only a prelude to its main science mission: to reach the base of the 5.5-km high Mount Sharp, which is located within Gale Crater. Once there, Curiosity will start investigating the mountain's different geologic layers, something that would give scientists a significant insight to the Red Planet's different geologic epochs, and how Mars' changing climate affected its habitability and the possible presence of life.
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