LAS CRUCES - NASA's White Sands Complex maintains a special link to Atlantis, now orbiting Earth as part of the last-ever U.S. space shuttle mission.
The complex is like a cell phone company, but for exclusive, mostly federal, space-related clients. It's the hot line that links astronauts and their command center in Houston, allowing them to talk to one another and to stream about 90 combined hours per day of real-time data.
In the current mission, the communications link started seven minutes after the shuttle's lift-off July 8 and will stop once Atlantis lands this week.
"When they're talking to the astronauts, they're talking through us," said Don Shinners, NASA station director for WSC. "We're like a direct pass-through."
The complex does the same job for the International Space Station and the Hubble Telescope, among other clients.
Headquartered at a 26-acre property in the foothills of the San Andres Mountains, the complex employs about 400 people and has an annual operating budget of about $45 million. Some personnel are federal employees, but most are contractors.
Two of its three main stations are located six miles and nine miles, respectively, north of U.S. Highway 70 near Organ.
A third station in Guam, where about 20 personnel are based, gives communications coverage to the space shuttle as it passes over the Indian Ocean. That station reports to Las Cruces.
The complex is important enough, Shinners said, that the shuttle wouldn't have launched
if there was a problem at the facility.
Another major component of the system is the network of eight high-dollar satellites that are orbiting geosynchronously - meaning they're in a fixed spot relative to Earth's surface.
The first WSC facility - called White Sands Ground Terminal - was finished in July of 1981, Shinners said.
It consists of a 56,100 square-foot building - packed with all the computers, radio equipment and other hardware needed for a sophisticated space communication network - and three super-sized antennas, each with a nearly 60-foot diameter.
The construction represented a shift in NASA's strategy for communicating with orbiting vehicles, Shinners said. Previously, the agency had maintained a number of ground stations around the world that made direct links to a spacecraft as it circled the globe - an expensive operation. But with the change, NASA instead began deploying satellites farther into space than the spacecraft, a distance that gave the devices a broad coverage area. It meant that fewer ground stations were needed.
Orbiting spacecraft now beam signals to the satellites, which shoot them back to White Sands Complex, which in turn relays them to the client. In the case of the shuttle, that client is the NASA's Houston-based shuttle command center.
The WSC was expanded when a second, 71,400 square-foot ground terminal was completed in April 1994, according to Shinners.
It included three more high-powered antennas and also became the complex's headquarters. The Guam facility was constructed in 1998, to get rid of a coverage gap.
In spite of WSC's significance, Shinners said, local residents most often don't realize what it does or that it's so close.
The Las Cruces area was selected as the site for the ground station partly because NASA already had access to land next to its White Sands Test Facility, Shinners said. Though located near one another, the two are run by different branches of the space agency.
Another reason was Las Cruces' location in the southern United States - closer to the equator is better - and its nearly perpetual sunshine, Shinners said. Plus, he said, natural disasters, which often cause evacuations of NASA facilities in other parts of the country, are rarely a concern.
Those factors are important because NASA can't afford to interrupt the satellite-ground station link when human lives are involved, as in the case of astronauts, Shinners said.
That's also why a continuous power supply is needed, Shinners said. The facility has a massive battery pack that switches on when El Paso Electric Co. service cuts out. Then diesel-powered generators kick in. During a severe freeze in February that caused rolling blackouts across the county, the generators ran for about two weeks, he said.
Shinners said the complex strives for a near-perfect communication link. For instance, on Wednesday, the facility carried out 545 combined hours of transmissions to the shuttle, space station and other customers with no interruptions.
"We didn't have one data outage," he said.
To run the facility, the complex employs a spectrum of employees, including satellite controllers, software programmers, diesel mechanics and HVAC mechanics, Shinners said.
"We're a 24-7, 365 facility," Shinners said.
A tour of the headquarters last week revealed the operations control room. Employees sat at eight banks of work stations, each intently monitoring an array of computer screens. From this room, it's possible to control the eight satellites.
Next door, tan-colored racks of equipment - think demodulators, bit synchronizers, base band equalizers and receivers - fill a room the size of a football field. It's been running non-stop since its installation in the early 1990s.
Though installed in the '90s, the equipment was made in the 1980s and has become outdated, Shinners said. It's slated to be replaced.
Scott Smith, a senior manager for one of the facility's subcontractors, ASRC, said the replacement will include the same types of equipment currently there, but it will take up much less space.
"We're excited about it," said Smith, who's worked for various contractors at the complex since 1988.
Shinners said he describes employees' efforts as "heroic," because they're working with such old equipment, but achieving such a high rate of performance. They understand astronauts' lives are at stake, he said.
"They really take their job and performance so seriously," he said.
Though the shuttle program is retiring, White Sand Complex won't see a reduction in its work force, Shinners said. He said that's because the facility serves other clients, including some in the private sector. For instance, he said the facility has had discussions with SpaceX, a California company with sights set on orbital spaceflight.
WSC's involvement with commercial spaceflight companies is only likely to grow as that industry develops, Shinners said.
That's because the complex offers the best way to guarantee communications in a low-Earth orbit - a range of about 100 to 1,200 miles above Warth, Shinners said.
"Because we provide 99.9-plus percent services to the customer, we're the most reliable network that a customer would want to use," he said. "Plus, it's continuous coverage as they orbit the Earth."
• July 1981: White Sands Ground Terminal completed
• April 1994: Second TDRSS Ground Terminal completed
• February 1996: White Sands Ground Terminal upgrade completed
• July 1998: Guam Remote Ground Terminal becomes operational
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