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Under the unflinching summer sun, workers at NASA's Deep Space Network complex in Goldstone, Calif., use a crane to lift a runner segment that is part of major surgery on a giant, 70-meter-wide antenna. Image credit: NASA/JPL-Caltech

On May 3, 2010, workers at the Deep Space Network's Goldstone Deep Space Communications Complex removed one of the large steel pads that help the giant "Mars antenna" rotate sideways. Image credit: NASA/JPL-Caltech

PASADENA, Calif. –The seven-month upgrade to the historic "Mars antenna" at NASA's Deep Space Network site in Goldstone, Calif. has been completed. After a month of intensive testing, similar to the rehabilitation stage after surgery, the antenna is now ready to help maintain communication with spacecraft during the next decade of space exploration.

The month of October was used as a testing period to make sure the antenna was in working order and fully functional, as scheduled, for Nov. 1. A team of workers completed an intense series of tasks to reach its first milestone – upgrading the 70-meter-wide (230-foot-wide) antenna in time to communicate with the EPOXI mission spacecraft during its planned flyby of comet Hartley 2 on Nov. 4.

The first official demonstration space track was on Sept. 28, when the antenna communicated with NASA's EPOXI mission spacecraft.

"We've been testing the antenna since Sept. 28, and we've had no problems in tracking the spacecraft," said Peter Hames of NASA's Jet Propulsion Laboratory, Pasadena, Calif., who is responsible for maintaining the network's antennas. "We are ready to resume service as scheduled." JPL manages the Deep Space Network for NASA.

During the upgrade process, workers raised a portion of the antenna that weighs 3.2 million kilograms (7 million pounds) up from the base by 5 millimeters (0.2 inches) while they performed a precise, delicate repair. They replaced a portion of the hydrostatic bearing (enabling the antenna to rotate horizontally) and the four elevation bearings (enabling the antenna to track up and down from the horizon).

Unlike the sterile confines of an operating room, this surgery took place in the middle of California's Mojave Desert, a hot oasis baked by the unforgiving desert heat. The team members were able to cheat the heat by completing a number of the 375 tasks during early morning and night shifts. The tasks required the team to analyze, load, lift, install, test, analyze again and inspect.

The Deep Space Network consists of three deep-space communication facilities positioned approximately 120 degrees of longitude apart. In addition to the Mojave Desert location at Goldstone, the other locations are outside of Madrid, Spain, and Canberra, Australia. Each 70-meter (230-foot) antenna is capable of tracking a spacecraft traveling more than 16 billion kilometers (10 billion miles) from Earth. The antennas are strategically situated at each location in semi-mountainous basins to reduce radio frequency interference. This careful placement helps make the Deep Space Network the largest and most sensitive science telecommunications system in the world.

In March 1966, the antenna, officially known as Deep Space Station 14, earned its nickname as the Mars antenna because its first-ever signal came from NASA's Mariner 4 mission to Mars. The historic dish is now responsible for tracking an entire fleet of missions, including the rovers Spirit and Opportunity currently on the surface of Mars, the Cassini orbiter at Saturn, the twin Voyager spacecraft in the outer reaches of our solar system, and the Spitzer Space Telescope, which observes stars, galaxies and other celestial objects.

"We are nearing the completion of a very challenging engineering effort that will extend the life of one of the DSN's workhorses, making it more available and reliable in returning critical science data through at least 2025," said Wayne Sible, the network's deputy project manager at JPL.

The antenna upgrade was a collaborative effort between JPL, Diani Building Corp., Santa Maria, Calif., and ITT Corp., White Plains, N.Y. Their shared goal was to emerge from the "operating room" with a healthy patient.

"The 70-meter antenna gets under your skin, everyone involved in this project was so passionate about it, from the grout workers to the machine shops to the guys on the antenna, everybody was giving it their absolute all," said Hames.

JPL, a division of the California Institute of Technology in Pasadena, manages the Deep Space Network for NASA Headquarters, Washington.

More information about the Deep Space Network is online at: http://deepspace.jpl.nasa.gov/dsn .

The American Recovery and Reinvestment Act of 2009 (Recovery Act) was signed into law by President Obama on February 17th, 2009. It is an unprecedented effort to jumpstart our economy, create or save millions of jobs, and put a down payment on addressing long-neglected challenges so our country can thrive in the 21st century. The Act is an extraordinary response to a crisis unlike any since the Great Depression, and includes measures to modernize our nation's infrastructure, enhance energy independence, expand educational opportunities, preserve and improve affordable health care, provide tax relief, and protect those in greatest need.

Among the key purposes of the Recovery Act are preserving and creating jobs, spurring technological advances in science and health, and promoting economic recovery. NASA has an important role to play in achieving these purposes through the program and facilities investments it will make with Recovery Act funding. As NASA develops and begins implementing its plans, this site will be one of the Agency's primary ways for communicating NASA's plans, progress, and results.

The President and Congress are committed to spending these recovery dollars with an unprecedented level of transparency and accountability so Americans know where their tax dollars are going and how they are being spent. Meeting these commitments will require sustained focus by all of us at NASA, particularly in planning, awarding, managing, and overseeing the contracts and grants through which the objectives of the Recovery Act will be achieved.

Recovery.gov is a website that empowers Citizens to hold the government accountable for every dollar spent. NASA, along with every other federal agency, is required to provide spending and performance data on a weekly, monthly, quarterly, and as required basis.

We invite you to visit us regularly and hear about the exciting work NASA is doing to contribute to America's economic recovery.

By the end of April, NASA will be working with Congress and the Office of Management and Budget to finalize its Recovery plans. As these plans are approved and they are implemented, we will be posting the latest Agency Plans and Reports here.

The Administration's priorities entrust NASA with $1 billion for Recovery investments. Among the purposes for these funds indicated by Congress include:

American scientists claim to have found evidence that suggests Mars had a warm and wet climate which could have supported life some 3.5 billion years ago.

A team, led by planetary geologists at Brown University, found mounds of a mineral deposited on a volcanic cone less than 3.5 billion years ago that speak of a warm and wet past, and may preserve evidence of one of the most recent habitable microenvironments on the red planet.

Observations by the National Aeronautics and Space Administration's Mars Reconnaissance Orbiter enabled the researchers to identify the mineral as hydrated silica which can be dissolved, transported and concentrated by hot water or steam - a dead ringer that water was present at some time.

Best evidence yet

The mineral and the mounds' location on the flanks of a volcanic cone provide the best evidence yet on Mars for an intact deposit from a hydrothermal environment — a steam fumarole or a hot spring, said the researchers.

Such environments might have provided habitats for some of Earth's earliest life forms, they hoped.

“The heat and water required to create this deposit probably made this a habitable zone,” said J. R. Skok, lead author of the study, published in journal Nature Geoscience.

“If life did exist there, this would be a promising spot where it would have been entombed - a microbial mortuary, so to speak.”

Favourable climate

No studies have determined whether Mars has ever supported life, but this finding adds to accumulating evidence that at some times and in some places, Mars hosted favourable climate for microbial life.

The deposit is located in the sprawling, flat, volcanic zone known as Syrtis Major and was believed to have been left during the early Hesperian period, when most of Mars was already turning chilly and arid.

“Mars is just drying out,” Skok said, “and this is one last hospitable spot in a cooling, drying Mars.”

Concentrations of hydrated silica have been identified on Mars previously, including a nearly pure patch found by NASA's Mars Exploration Rover Spirit in 2007. However, this is the first found in an intact setting that clearly signals the mineral's origin.

“You have spectacular context for this deposit,” Skok said. “It's right on the flank of a volcano. The setting remains essentially the same as it was when the silica was deposited.”

Bright deposits

Observations by cameras on the Mars Reconnaissance Orbiter revealed patches of bright deposits near the summit of the cone, fanning down its flank, and on flatter ground in the vicinity.

The Brown researchers partnered with Scott Murchie, of Johns Hopkins University Applied Physics Laboratory, to analyse the bright exposures with the Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) instrument on the orbiter.

Hydrated silica identified by the spectrometer in uphill locations, confirmed by stereo imaging, indicates that hot springs or fumaroles fed by underground heating created these deposits. Silica deposits around hydrothermal vents in Iceland are among the best parallels on Earth.

“The habitable zone would have been within and alongside the conduits carrying the heated water,” Murchie said.

The International Space Station -- which is coming up on a decade of continuous human habitation -- is a celebrated success in our species' quest to learn to live in space. Yet life in orbit has its serious trials, and mishaps along the way have proven just how much we still have to learn about being a spacefaring civilization.

In honor of Halloween, here are 10 ways space station living can become a little horror story:

10. Fingernails fall off

The spacesuit gloves astronauts wear while working outside the station during spacewalks have proven to be hazardous to their health.

A recent study found that about 10 percent of astronauts are victims of "fingernail trauma" from gloves, with a number of them losing a fingernail entirely because the glove pinched their fingers and reduced circulation.

Typically, the damage is worse the larger an astronaut's hand is. Maybe NASA should look for petite spaceflyers.

9. Weightless worries

Weightless living can have some pretty odd consequences without even going outside. Take, for example, the attack of the flying wasabi.

In March 2007 astronaut Sunita Williams was trying to squeeze some of the spicy green condiment onto her makeshift space sushi, when a squirt got loose, ultimately splattering the walls with wasabi and hiding stray droplets around the module.

It took a while to get the wasabi smell out after it had flown all over the place, Williams said at the time. And she had to forgo wasabi on future space meals, saying it was just "too dangerous."

8. Rough ride

While floating on the space station can be fun, getting to and from it can be a rough ride. Trips on the Russian Soyuz spacecraft, in particular, reportedly pack quite a punch of G forces.

"I've heard it described as a train wreck followed by a car crash followed by falling off your bike," NASA astronaut Tracy Caldwell Dyson said recently before she flew home from the station on one herself.

After she had experienced the trip, she said the rumors were dead on.

"It certainly didn't disappoint," Caldwell Dyson told SPACE.com after her return. "All the bangs, bells, whistles and sensations were there. The magnitudes of some things were a little surprising, but for the most part it was a pretty exciting ride."

7. Space diet of baby food

Though it's not just Tang and freeze-dried ice cream these days, food in space still leaves something to be desired.

Fresh fruit and vegetables are scarce, for example, and ground staples like bread are impractical because they leave crumbs, which in microgravity fly around everywhere instead of settling on the floor, and become a disaster to clean up. (Instead astronauts favor tortillas, which create fewer crumbs).

And astronauts tend to get sick of the same roster of re-heatable meals rotated on an eight-day schedule.

In the winter of 2004, however, an unmanned cargo ship due to deliver fresh food and supplies to the space station was delayed. In response, the crewmembers onboard – Expedition 10 commander Leroy Chiao of NASA and flight engineer Salizhan Sharipov of Russia – had to ration their meals.

The two ended up cutting their regular food consumption in half to conserve supplies, then making up for the lost calories by eating abundant desserts and candies. "It wasn't an unhealthy diet, but it wasn't an ideal diet either," Chiao said at the time.

6. Cramped quarters

While the station has grown considerably over the 10 years it's been permanently inhabited, many spaces are still a tight squeeze. And for the last year and a half, the normal crew size aboard the orbiting lab have been six, meaning what space there is has been shared by more bodies.

Sleeping can be particularly cramped inside an astronaut's "crew quarters" – essentially an alcove the size of a phone booth – and there are other hazards of catching some Zzz's in a free floating sleeping bag.

"During the night while you're sleeping, you might start drifting and end up somewhere you didn't intend to be in the first place," Canadian astronaut Julie Payette said in 2009.

Yet overall, the coziness of slumbering without gravity's incessant pull makes sleeping in space rather comfy, Payette said.

5. Hygiene hiccups

The lack of showers in space often puts a serious damper on the experience.

Microgravity makes it impossible to have a normal shower where water falls from a stream and falls docilely into a drain. Instead, astronauts on the International Space Station use a squirt gun that shoots out water and a wash cloth. They also have a special rinse-less shampoo to keep their hair clean.

"We wash like we would if we were on an expedition or a camping trip or something," Payette explained. "It works."

Still, who wants to keep that up for six months? Especially with the aforementioned tight living quarters!

4. Toilet troubles

One of the peskiest recurring problems on the station is the toilet situation.

There are two toilets on the space station – one in the Russian segment, and one in the United States modules. But both have been balky, breaking and requiring on-orbit plumbing jobs to get them working again.

Then there's the issue of what happens to the waste water – as of May 2009, urine is recycled into clean drinking water, and is also recycled into water for bathing and food preparation.

"It's sort of one of those horrible and fascinating kind of things. It's like, 'You're going to drink urine?'" said astronaut Sandra Magnus, who was living on the station when the urine recycling system was installed. "We're not, we're drinking processed water that started as urine."

3. Creaky bones

Beyond the daily nuisances, astronauts have to deal with serious health consequences from their time in orbit. One of the most significant of these is the effect on their bones.

A recent study found that astronauts' bone strength dips by at least 14 percent during a half-year stay in space. Other research indicates that an astronaut's bone mineral density can decrease by between 0.4 percent and 1.8 percent each month they are on the station, leading to greater risks of fractures and osteoporosis later in life.

While there is no complete fix for this problem, astronauts are diligent about bone-strengthening exercises while they're on the station, and undergo extensive rehabilitation once they're back on the ground to try to avoid possessing the bones of a 90-year-old.

2. Losing your lunch

Space sickness, too, can affect the best of 'em.

Acclimatizing to life in zero gravity, especially since no simulator can reproduce microgravity on the ground, takes time. It's not uncommon for astronauts to lose their lunch after liftoff before they even reach the space station.

And, to make matters worse, spewing chunks in space creates rather more of a mess than it would on Earth, since projectile vomit doesn't project toward the ground.

1. The loneliest number

Perhaps the hardest part of life in space is the feeling of isolation astronauts can get when they spend half a year removed from the whole planet, especially their friends and family. While astronauts can combat the loneliness by bonding with crewmates and making frequent calls home, they sometimes have to miss major life events back on Earth.

In December 2007, NASA astronaut Daniel Tani's mother died in a car accident while he was living on the space station. Tani had to grieve from more than 200 miles away in orbit, until he came back to Earth about two months later.

And in 2004, NASA astronaut Michael Fincke was forced to miss the birth of his second child, when his wife gave birth to daughter Tarali while he was serving a long-duration mission during the station's Expedition 9. He was able to meet his daughter four months later when he finally landed.

• Graphic: Inside and Out: The International Space Station
• Video: Astronaut Describes Riding Home on a Soyuz, Soyuz Landing Photos
• Space Station Life Has its Ups and Downs, Astronaut Says

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