Top of the World Tracking
Written by Scott R. Gourley
They're not quite at the "top of the world," but at 76.5 degrees N/68.6 degrees W, Detachment 3 (Det 3) of the Air Force 22 Space Operations Squadron (SOPS) is certainly well positioned to deal with polar orbiting satellites. Popularly designated by call sign POGO, the Thule Tracking Station, Greenland, falls under the 14th Air Force (Space Operations) 50th Space Wing, which commands Air Force Space Command's Air Force Satellite Control Network (AFSCN).
The AFSCN is divided between the two hemispheres, according to Major Florian DeCastro, detachment commander. The Western Hemisphere contains the majority of the antennas: HULA (Detachment 4-Waianae, Hawaii); COOK (Detachment 1-Vandenberg Air Force Base, Calif.); PIKE (22 SOPS-Schriever Air Force Base, Colo.); BOSS (23 SOPS-New Boston Air Force Station, N.H.); and POGO, the largest AFSCN site. AFSCN also has three locations in the Eastern Hemisphere: LION (belongs to the United Kingdom-operating location, Oakhanger, U.K.); REEF (Detachment 2-Diego Garcia); and GUAM (Detachment 5-Andersen Air Force Base, Guam).
The AFSCN operation is a "high-demand/low-density asset," DeCastro said, noting that there are just 15 satellite antennas for more than 170 satellites in orbit. With three of those antennas, POGO is the largest site in the network.
"Commanding and controlling the entire network are two operational control nodes. Shriever is our primary, under 22 SOPS. And 21 SOPS, our backup control node, is at Sunnyvale, Calif.," he explained.
(Recent Base Realignment and Closure decisions directed the closure of Onizuka Air Force Station in Sunnyvale, with the likely transfer of that mission down to Vandenberg by the end of fiscal year 2011.)
"22 SOPS is the command and control center for the entire AFSCN network," he said. "They develop the network tasking order, similar to the air tasking order. And they provide radio frequency interference safety, so that we don't unintentionally or inadvertently 'beam' or hit another satellite with electronic energy. If we're talking to a satellite in geostationary orbit, more than 20,000 miles away, we don't want to inadvertently 'turn on' and hit another satellite, like a GPS satellite, below it."
Command and Control
Along with the Network Tasking Order, 22 SOPS missions include command and control and space safety analysis.
In terms of services, DeCastro noted that AFSCN supports "any DoD or federal launches in some form or fashion, primarily DoD-the military constellations-but also the space shuttle. When the space shuttle is up in orbit, we provide support for them, because we are really the most all-encompassing ground network. There are other ground networks out there. The Navy has its own and NASA has its own. But as far as global outreach and capabilities, we have the most. And we support a lot of people with our network. The NASA network, for example, is dedicated just for NASA. They can't support other agencies, whereas we can.
"Another term we like to use is that we are the 911 of space, because anybody that's having problems up there can come onto our network," he added.
While supporting a wide array of launch and early orbit activities, the majority of AFSCN mission services involve payload and "bus" management, or telemetry, tracking and command. The final mission area involves mission data dissemination.
"We download whatever information the satellite may have," DeCastro said. "If it is a weather satellite, whatever sensors it has or whatever pictures it may have taken, we would download the raw data. We have no way of actually knowing what that data is. It's just ones and zeros that come down to us. But at the distant end, the operational center where we connect, they can see exactly what the information is."
"Our mission for Detachment 3 is to perform telemetry, tracking and commanding operations, not just for the U.S. but also for our allied partners. And our bottom line is to provide assured access to space for our allies, our partners and for the combatant commanders," he observed.
Det 3 operations are performed by a team that includes Air Force personnel, Greenlandic support personnel, a network systems integration contractor (Honeywell), and 20 to 30 Network and Space Operations and Maintenance (NSOM) team members. Harris announced last year that it had been selected by the Air Force for the NSOM program, which contains a base contract and six options that bring the potential overall value to $410 million over six and a half years. The company committed to provide operations and maintenance support to the 50th Space Wing's Air Force Satellite Control Network at locations around the world.
The Harris IT Services-led NSOM team comprises Lockheed Martin Information Technology, L-3 Communications Titan Group, Faith Enterprises, ASRC Aerospace, Arctic Slope World Services, Nortel Government Solutions and Günther Douglas.
When the satellites come within view of the tracking station, the ground element "connects up to it and downloads whatever information it may have, or sends commands up to the satellite to do whatever it needs to do," DeCastro explained. "We can only monitor the satellites that we can actually talk to," he added. "Most of the 'space junk' or the satellites that are out there from other countries are monitored by the Ballistic Missile Early Warning System."
Given its location approximately 700 miles north of the Arctic Circle, Det 3 is ideally situated to perform its mission set for polar orbiting satellites.
"That's the reason why we're here," DeCastro said. "If you visualize our other AFSCN sites in California, Colorado or New Boston, those sites may only see these polar orbiting satellites once a day or once every couple of days. But we can see all those satellites every day, about 10 to 12 times a day."
Citing the example of a Defense Meteorological Support Program satellite, he added, "This orbit right here is about a 90-minute orbit. So every 90 minutes we have a satellite on station up here. So we're a guaranteed way of getting the data."
He noted that "time on station" for each satellite is a function of altitude, with higher altitude satellites being in communication for longer periods.
After dismantling POGO-D (data link terminal) in 2006, current Det 3 resources include POGO-B (46-foot antenna in 68-foot radome, built in 1979, 2000W Uplink), POGO-C (33-foot antenna in 53-foot radome, built in 1987, 2000W Uplink), and POGO-A (37-foot antenna in 60-foot radome, built in 1999, 2000W Uplink).
Simultaneous Data Streams
In terms of telemetry, capabilities include the satellite data download of up to five simultaneous data streams, as well as state-of-health and/or mission payload data. For satellites ranging from 100 to 448,000 miles above the earth, tracking data is accurate to a range of less than 2.5 meters with range rate accuracies of 1 cm/second. "One mile in space is very, very close," DeCastro observed. "But we can actually get much closer than that, because we can talk to the satellite and determine exactly where it's at as a more refined point."
In terms of "customer mix," he noted that POGO-supported satellites include navigation, research and development/NASA, Defense Support Program/Space Based Infrared System early warning, weather and ISR.
The commander noted that the absence of communications satellites reflects Det 3's northern location and the difficulties of "seeing" their non-polar orbits.
"Our mission is to provide assured access to space for the combatant commander and provide mission services through DoD and our allied partners," DeCastro said. "And we do that by commanding and controlling the entire Air Force Satellite Control Network and producing a network tasking order that divvies out our high-demand/low-density asset-15 antennas for about 170 satellites up there." ♦
The AFSCN is divided between the two hemispheres, according to Major Florian DeCastro, detachment commander. The Western Hemisphere contains the majority of the antennas: HULA (Detachment 4-Waianae, Hawaii); COOK (Detachment 1-Vandenberg Air Force Base, Calif.); PIKE (22 SOPS-Schriever Air Force Base, Colo.); BOSS (23 SOPS-New Boston Air Force Station, N.H.); and POGO, the largest AFSCN site. AFSCN also has three locations in the Eastern Hemisphere: LION (belongs to the United Kingdom-operating location, Oakhanger, U.K.); REEF (Detachment 2-Diego Garcia); and GUAM (Detachment 5-Andersen Air Force Base, Guam).
The AFSCN operation is a "high-demand/low-density asset," DeCastro said, noting that there are just 15 satellite antennas for more than 170 satellites in orbit. With three of those antennas, POGO is the largest site in the network.
"Commanding and controlling the entire network are two operational control nodes. Shriever is our primary, under 22 SOPS. And 21 SOPS, our backup control node, is at Sunnyvale, Calif.," he explained.
(Recent Base Realignment and Closure decisions directed the closure of Onizuka Air Force Station in Sunnyvale, with the likely transfer of that mission down to Vandenberg by the end of fiscal year 2011.)
"22 SOPS is the command and control center for the entire AFSCN network," he said. "They develop the network tasking order, similar to the air tasking order. And they provide radio frequency interference safety, so that we don't unintentionally or inadvertently 'beam' or hit another satellite with electronic energy. If we're talking to a satellite in geostationary orbit, more than 20,000 miles away, we don't want to inadvertently 'turn on' and hit another satellite, like a GPS satellite, below it."
Command and Control
Along with the Network Tasking Order, 22 SOPS missions include command and control and space safety analysis.
In terms of services, DeCastro noted that AFSCN supports "any DoD or federal launches in some form or fashion, primarily DoD-the military constellations-but also the space shuttle. When the space shuttle is up in orbit, we provide support for them, because we are really the most all-encompassing ground network. There are other ground networks out there. The Navy has its own and NASA has its own. But as far as global outreach and capabilities, we have the most. And we support a lot of people with our network. The NASA network, for example, is dedicated just for NASA. They can't support other agencies, whereas we can.
"Another term we like to use is that we are the 911 of space, because anybody that's having problems up there can come onto our network," he added.
While supporting a wide array of launch and early orbit activities, the majority of AFSCN mission services involve payload and "bus" management, or telemetry, tracking and command. The final mission area involves mission data dissemination.
"We download whatever information the satellite may have," DeCastro said. "If it is a weather satellite, whatever sensors it has or whatever pictures it may have taken, we would download the raw data. We have no way of actually knowing what that data is. It's just ones and zeros that come down to us. But at the distant end, the operational center where we connect, they can see exactly what the information is."
"Our mission for Detachment 3 is to perform telemetry, tracking and commanding operations, not just for the U.S. but also for our allied partners. And our bottom line is to provide assured access to space for our allies, our partners and for the combatant commanders," he observed.
Det 3 operations are performed by a team that includes Air Force personnel, Greenlandic support personnel, a network systems integration contractor (Honeywell), and 20 to 30 Network and Space Operations and Maintenance (NSOM) team members. Harris announced last year that it had been selected by the Air Force for the NSOM program, which contains a base contract and six options that bring the potential overall value to $410 million over six and a half years. The company committed to provide operations and maintenance support to the 50th Space Wing's Air Force Satellite Control Network at locations around the world.
The Harris IT Services-led NSOM team comprises Lockheed Martin Information Technology, L-3 Communications Titan Group, Faith Enterprises, ASRC Aerospace, Arctic Slope World Services, Nortel Government Solutions and Günther Douglas.
When the satellites come within view of the tracking station, the ground element "connects up to it and downloads whatever information it may have, or sends commands up to the satellite to do whatever it needs to do," DeCastro explained. "We can only monitor the satellites that we can actually talk to," he added. "Most of the 'space junk' or the satellites that are out there from other countries are monitored by the Ballistic Missile Early Warning System."
Given its location approximately 700 miles north of the Arctic Circle, Det 3 is ideally situated to perform its mission set for polar orbiting satellites.
"That's the reason why we're here," DeCastro said. "If you visualize our other AFSCN sites in California, Colorado or New Boston, those sites may only see these polar orbiting satellites once a day or once every couple of days. But we can see all those satellites every day, about 10 to 12 times a day."
Citing the example of a Defense Meteorological Support Program satellite, he added, "This orbit right here is about a 90-minute orbit. So every 90 minutes we have a satellite on station up here. So we're a guaranteed way of getting the data."
He noted that "time on station" for each satellite is a function of altitude, with higher altitude satellites being in communication for longer periods.
After dismantling POGO-D (data link terminal) in 2006, current Det 3 resources include POGO-B (46-foot antenna in 68-foot radome, built in 1979, 2000W Uplink), POGO-C (33-foot antenna in 53-foot radome, built in 1987, 2000W Uplink), and POGO-A (37-foot antenna in 60-foot radome, built in 1999, 2000W Uplink).
Simultaneous Data Streams
In terms of telemetry, capabilities include the satellite data download of up to five simultaneous data streams, as well as state-of-health and/or mission payload data. For satellites ranging from 100 to 448,000 miles above the earth, tracking data is accurate to a range of less than 2.5 meters with range rate accuracies of 1 cm/second. "One mile in space is very, very close," DeCastro observed. "But we can actually get much closer than that, because we can talk to the satellite and determine exactly where it's at as a more refined point."
In terms of "customer mix," he noted that POGO-supported satellites include navigation, research and development/NASA, Defense Support Program/Space Based Infrared System early warning, weather and ISR.
The commander noted that the absence of communications satellites reflects Det 3's northern location and the difficulties of "seeing" their non-polar orbits.
"Our mission is to provide assured access to space for the combatant commander and provide mission services through DoD and our allied partners," DeCastro said. "And we do that by commanding and controlling the entire Air Force Satellite Control Network and producing a network tasking order that divvies out our high-demand/low-density asset-15 antennas for about 170 satellites up there." ♦