NASA Reinstates Canceled NuSTAR Astronomy Mission










NASA will restart a




$140 million Small Explorer-class astronomy mission that fell victim to the




budget ax in early 2006,




the U.S. space agency announced Sept. 21.

The Nuclear Spectroscopic Telescope Array, or NuSTAR for short, was headed toward




a successful confirmation review early last year when NASA’s science chief at the time, Mary Cleave, announced during a budget briefing that the Jet Propulsion Laboratory-managed project would not go forward. Scientists blasted NASA’s decision to abruptly cancel a competitively selected mission that was encountering neither budgetary nor technical setbacks.

In a statement, Alan Stern, NASA’s current science chief,




said




restarting NuSTAR is an example of how the agency is “getting more and more from the science budget we have.”

Slated for launch in 2011, the spacecraft is expected to bridge a gap between the 2009 launch of the Wide-field Infrared Survey Explorer and the 2013 launch of the James Webb Space Telescope.

Fiona Harrison of the California Institute of Technology, Pasadena, is the NuSTAR principal investigator. Dulles, Va.-based Orbital Sciences Corp. is the industry partner for the mission.







Satellite Delay Forces Sea Launch to Postpone



Sea Launch Co.’s planned late-October return to flight has been postponed until mid-November because the payload,




the Boeing-built Thuraya 3 mobile telecommunications satellite, has been delayed, Sea Launch and Boeing officials said.

Boeing wants additional time to check Thuraya 3 in light of what Boeing said is a minor anomaly on a recently launched Boeing commercial satellite, which the company declined to name. The anomaly, which according to Boeing




has not impaired the performance of the affected satellite, will not delay the scheduled early October launch of the U.S. Defense Department’s Wideband Global Satcom (WGS) spacecraft aboard a United Launch Alliance Atlas 5 rocket, a Boeing official said.

Thuraya
and WGS both use Boeing’s 702 satellite frame.

Thuraya
3 is now expected to be delivered to Sea Launch’s Long Beach, Calif., home port in time for a mid-November launch from Sea Launch’s floating platform, which operates at




a mid-Pacific Ocean location on the equator.

Sea Launch President Rob Peckham said the Odyssey platform, which sustained damage in the January failure of the company’s




Zenit
3SL rocket, has about finished its refurbishment and would have been ready for a late-October launch.

While a delay of several weeks in satellite deliveries is common, this one will be particularly painful for Sea Launch, which had hoped to conduct two campaigns before the end of the year. The next Sea Launch customer, DirecTV Group’s DirecTV-11 satellite – also a Boeing 702 – is unlikely to be launched before January, Peckham said.

Before the failure, Sea Launch had hoped to conduct five to six launches during the year.




TacSat-3 Launch Delayed Due to Component Issues



Component




problems have delayed the




launch of the U.S. Air Force’s experimental




TacSat-3 satellite




until June 25, according to the service’s TacSat-3 program manager.




TacSat-3, one of a series of small




spacecraft




designed to




bring information to the battlefield rapidly, is slated to




launch




from NASA’s




Wallops Flight Facility in Virginia aboard a Minotaur 1 rocket built by Orbital Sciences Corp. As of this past May, the launch was supposed to take place in December.



Thom Davis, who oversees the TacSat-3




program at the Air Force Research Laboratory (AFRL)




, said via




e-mail that the delay was due to




thermal issues with the optical link between the spacecraft’s sensor processor and communications system. Another factor was




the need to upgrade mirror mounts on




TacSat-3’s Artemis hyperspectral imaging




payload to better handle




launch vibration, he said




.

Davis said these




issues have been resolved, and the new launch date will provide enough time for detailed




testing and validation of the




satellite and




flight software.

Meanwhile, AlliantTechsystems announced Sept. 18 it has




delivered the TacSat-3 spacecraft platform, or bus,




to AFRL for integration and testing. The bus was designed and built at Alliant’s Beltsville, Md., space hardware facility.




Boeing Delta 2 to Loft 3rd Cosmo-Skymed Satellite



A Boeing commercial Delta 2 rocket will place Italy’s




third




Cosmo-Skymed civil-




military radar reconnaissance satellite into low Earth orbit in 2008 under a contract that Boeing announced Sept. 20.

A Boeing Delta 2 successfully launched the first of four planned Cosmo-Skymed satellites in June from Vandenberg Air Force Base, Calif., and a second Cosmo-Skymed is being prepared for a Delta 2 launch scheduled for late this year. Italy has yet to book a




launch for




the fourth and final Cosmo-Skymed satellite, tentatively planned for deployment




in 2009.

The Cosmo-Skymed satellites are considered as principally for military use by the Italian Defense Ministry, but the Italian Space Agency financed a large portion of their development and Italian authorities have said they will make some imagery available for sale.

Italian government and industry officials said the first Cosmo-Skymed is still being tested in orbit but that the satellite is performing to specification. No images have been released to the public, however.







Orbcomm is Target of Class-Action Lawsuits





Two U.S. law firms are seeking clients for class-action lawsuits against satellite-messaging service provider Orbcomm Inc., alleging that Orbcomm misled investors about its revenue outlook as it prepared the company’s initial public offering of stock last November.

Coughlin Soia of New York and and Brodsky & Smith LLC of BalaCynwyd, Pa., said they filed their separate securities class-action lawsuits in the U.S. District Court for the District of New Jersey. Orbcomm is headquartered in Ft. Lee, N.J.

Orbcomm’s
stock, traded since November on the U.S. Nasdaq exchange, tumbled this summer when the company said new contracts that had been expected this year likely would be delayed, forcing a downward revision of its full-year revenue forecast. Company officials said the issue was only one of contract timing and that they still expected the business to be booked.




Hamel Pleads Case for Only 3 Advanced EHFs





The U.S. Air Force will be saddled with big bills in future years if Congress forces it to spend $125 million in 2008 to begin procurement of a fourth Advanced Extremely High Frequency (EHF) secure communications satellite, according to Lt. Gen. Mike Hamel, commander of the Air Force Space and Missile Systems Center.





The House version of the 2008 defense spending bill




, which passed the House




Aug. 5, added $125 million to the




Air Force’s $611 million Advanced EHF budget request for the fourth satellite. The Senate Appropriations Committee followed suit in its version of the legislation, still awaiting a vote on the Senate floor.



The Air Force wants to buy three Advanced EHF satellites before moving on to the Transformational Satellite Communications System, or T-Sat. Speaking to reporters Sept. 19, Hamel said buying a fourth Advanced EHF would help avoid a coverage gap if T-Sat is delayed, but noted that such insurance would come at the expense of other programs in the years ahead. “It’s a zero sum game,” he said.





Meanwhile, Hamel said the Senate bill’s recommendation to trim $200 million from the Air Force’s $963.6 million T-Sat request would force the service to either forgo some of its planned risk reduction work – such as




designing contingency plans and maintaining alternate component suppliers –




or delay the first launch. T-Sat is slated to begin launching around 2016.








Summer Months Prove Lucrative for Iridium



Iridium Satellite LLC added 22,000 net subscribers during the three-month period ending Aug. 31,




setting company records for subscriber growth and total airtime used during a quarter, Iridium




announced in a Sept. 19 press release.

That growth is significantly larger than Iridium experienced during the same quarters




in 2006 and 2005, when it added 9,000 and 7,000 subscribers, respectively.




The




company’s total satellite communications subscriber base now stands at




around 216,000, Iridium spokesperson Liz DeCastro said.



Much of the growth came in North America, where a new aggressive pricing plan and defections from other communications service




providers accounted for most of the upswing, the press release said.







Spanish Defense Ministry Invests in Radar Satellite



The Spanish Defense Ministry has committed 112.5 million euros ($156 million) for the construction of a high-resolution radar satellite to be launched in 2011 for military and civil-security applications, a decision that would bring to 10 the number of European military radar spacecraft expected to be in orbit by then, according to a Spanish Defense Ministry official.

Lt. Col. Juan Andres Toledano, who represents Spain’s arms procurement agency, DGAM, in the multinational body that manages the French-led Helios optical reconnaissance system’s use, said the Ingenio satellite, also known as SeoSAR, will carry a synthetic-aperture radar (SAR) payload and would be integrated into an emerging pan-European system to facilitate multinational tasking of reconnaissance satellites.

Toledano
, addressing the 2nd International Conference on Military Space, organized here Sept. 17-19 by the French AAAF aerospace association, said the satellite also is intended as a technology-development program for Spain’s aerospace industry. Spain also is manufacturing a medium-resolution optical Earth observation satellite, called Seosat, with program-oversight contracted to the 17-nation European Space Agency.

Toledano
said Spanish government authorities, including the Defense Ministry and the Department of Trade and Industry, committed the funds for the satellite in late July.

Italy and Germany have both inaugurated their own high-resolution radar satellite systems. Two German SAR-Lupe radar satellites are in orbit, with three more scheduled for launch in the next 18 months. The first of four Italian Cosmo-Skymed satellites was launched earlier this year, with the remaining three to be launched by late 2009.

The Spanish Defense Ministry is a 7 percent shareholder in the French-led Helios 1 satellite program launched in the mid-1990s. The Helios 1A satellite is still operational, but the Helios 1B has been removed from service following an onboard battery failure. Spain is a 2.5 percent shareholder in France’s Helios 2 system, whose first satellite, Helios 2A, has been in orbit for two years. Spanish authorities have agreed to take a 3 percent share of France’s two Pleiades high-resolution optical satellites, scheduled to be launched in 2009 and 2010.

One Spanish official said SeoSAR may be operated as part of a constellation including Germany’s two civilian high-resolution radar satellites, TerraSAR-X and TanDem-X, through the Infoterra Earth observation services company, which would open a branch in Spain. TerraSAR-X is in orbit and TanDem-X is scheduled for launch in 2009.






European Satellite Center Relies on Commercial Data



The European Union Satellite Centre outside Madrid suffers from continued neglect despite the fact that it is the only pan-European organization capable of handling militarily sensitive space-based reconnaissance products, center Director France Asbeck said.

In the six years since the center was formally transferred to the European Union, its budget has dropped in inflation-adjusted terms. It is rising by less than 1 percent, to about 10 million euros ($13.9


million)




in 2007, only because new EU members Bulgaria and Romania are contributing for the first time. The center has a staff of about 74 people.

The center compiles reports on regional crises around the world at the request of one or more of its members or the EU’s top security and defense representative, Javier Solana, using mainly commercial satellite imagery purchased from U.S. companies.



“It’s worth noting that 80 percent of the imagery used in support of the [EU] European Security and Defense Policy comes from the United States,” Asbeck said. “The stability of this supply is not assured.”

A memorandum of understanding between France, the majority owner of the Helios optical reconnaissance satellites, and the EU that would give the center access to Helios imagery has still not been concluded despite four years of negotiations.

Asbeck
said the center’s budget for




imagery has been spent




mainly on purchasing data from the U.S. Ikonos satellite and the now-defunct OrbView-3




satellite, the Israeli Eros, Taiwan’s Formosat and South Korea’s Kompsat.






Italy Noncommittal on Launcher for Sicral 2



The Italian Defense Ministry, which already has irked Europe’s Arianespace launch consortium by selecting the U.S.-based Sea Launch Co. to launch its Sicral 1B military telecommunications satellite in late 2008, is not certain it will use Arianespace for its Sicral 2 spacecraft in 2011, an Italian defense official said.

Italian Navy Lt. Col. Giovanni Battista Durando said Italy will use the same cost-versus-service-life evaluation for Sicral 2 that it used for Sicral 1B. Sicral 1B is a relatively small satellite that, if launched as one of two passengers aboard an Ariane 5 vehicle, would have been dropped off in an orbit that would require it to use a relatively large amount of fuel to reach its final destination.

“For us it’s simply an operational consideration,” Durando said. “For Sicral 1B, we have an operational requirement of 13 years of service life. With an Ariane 5, we would have been given less than 9.5 years.”

Sicral
2 is likely to be a larger spacecraft that will carry military communications payloads for both Italy and France. It will replace the orbiting Sicral 1, which is scheduled to be retired in 2011.

A development contract for Sicral 2 has not been signed, but Durando said Italian authorities may well need to consider non-European rockets for the launch depending on the satellite’s final weight and service-life requirements.



Sicral 1B is being managed as an unusual collaboration between Italian defense authorities and Telespazio of Rome. Telespazio is providing




118 million euros ($163.




8 million) of




Sicral
1B costs, mainly related to the launch, in exchange for the right to sell some of the satellite’s UHF transmission capacity to allied governments.



Durando said Telespazio would be handling Sicral 1B service provision to NATO and will be reimbursed for its investment in part by NATO payments to Italy. Italy, France and Britain are sharing responsibility for providing UHF and SHF capacity to NATO under a long-term contract.

Durando
said the combined capacity of Sicral 1 and Sicral 1B will be sufficient to serve the Italian Defense Ministry and NATO, with some left over for sale by Telespazio to third-party customers.






Nations Face Deadline for Coordinating Recon Craft



The six European nations that have agreed to study a coordinated next-generation radar and optical reconnaissance system say


they have until mid-2008 to create a formal program directorate and funding mechanism or risk having their work collapse.



The six nations – France, Germany, Greece, Italy, Spain and Belgium – are trying to avoid a repeat of the situation that exists with today’s European space-based reconnaissance programs, which were developed separately and are difficult to modify to enable use by the six partners.



The six participating nations have created a loose network called MUSIS, or Multinational Space Imaging System, and have jointly financed several studies of how next-generation reconnaissance systems can be made part of a single, interoperable network.

Europe’s current military observation systems, operated by France, Germany and Italy, are all scheduled to be replaced around 2014. The MUSIS effort is designed to assure that these new systems are fully interoperable among the participating nations.

“There is an opportunity here despite the relative failure of cooperative efforts in the past,” said Jean-Maurice Vivier of Astrium Satellites, one of the companies performing MUSIS design work.

For MUSIS to fulfill its promise, it will have to be an integral part of the design of each nation’s next-generation reconnaissance system. The first deadline is in France, where planning for a third-generation Helios optical and infrared surveillance system already has begun. This early work will begin to face design deadlines in mid-2008.

“What we need from MUSIS nations is an agreement to create a legal structure that is empowered to set design architectures and distribute funding,” said Didier Alary of Astrium’s Earth observation directorate. “France will start freezing its early designs, for example its ground-to-satellite communications interfaces, in mid-2008. That is the MUSIS deadline and we cannot miss it.”








Industry Canada OKs Loral-Telesat Merger






Canada’s telecommunications regulatory body, Industry Canada, on Sept. 19 approved the acquisition of satellite operator Telesat Canada by New York-based Loral Space & Communications Inc. and Canada’s PSP Investments, Industry Canada and Loral said. The merger now awaits a similar go-ahead from U.S. regulators, which is expected in the coming weeks.

Loral will combine its Skynet satellite fleet with Telesat Canada’s and will have a 64 percent economic ownership of the merged company. PSP Investments, which manages pension funds for Canadian government employees, will have a 66.7 voting interest in the new company, retaining the Canadian control required by Canadian telecommunications law.

“Industry Canada has reviewed the transaction and has found that the new Telesat upon completion of the sale would remain Canadian-owned and controlled,” Industry Canada said




Sept. 20




in response to Space News inquiries. “As a result, Telesat was provided with Industry Canada’s conditional approval.”

Loral and PSP Investments agreed to purchase Ottawa-based Telesat Canada for 3.25 billion Canadian dollars ($3.16




billion) and the assumption of 172 million Canadian dollars in Telesat debt.

“[U.S. Federal Communications Commission] approval, the last regulatory approval required for the transaction, is expected shortly,” Loral Chief Executive Michael Targoff said in a Sept. 19 statement. “Completion of financing is being coordinated for a late October closing of the Telesat transaction, including the Loral Skynet business contribution.”







TerraSAR-X and TanDem-X Will Spot Moving Targets




Germany will be able to provide target indications of moving objects on the ground as small as 10 square meters – the size of a small boat – starting in 2009 once its TanDem-X radar satellite is in orbit and operating alongside the TerraSAR-X satellite launched in June, according to officials from prime contractor Astrium GmbH of Friedrichshafen, Germany.

By combining the two receive apertures on each of the satellites




and using filters to enhance a moving target’s visibility against its background, the TerraSAR-X and TanDem-X spacecraft will open new markets for its sponsors, officials said.

The two high-resolution radar satellites are being financed by a partnership between Astrium, the company’s Infoterra commercial-imagery




marketing division and the German Aerospace Center, DLR. The programs are being managed as civil-




commercial efforts that will lead to a commercial business for Infoterra. Most of the satellite data will not be classified but there likely will be restrictions on sales to governments not on friendly terms with Germany.



Christoph Schaefer of Astrium’s Earth observation division said TerraSAR-X already is providing rough data on moving targets, but the




radar processor occasionally “displaces” the target because it is incapable of calculating its movement with a single sensor.



One TerraSAR-X




image depicts




a Russian freight train that appears to be moving off the railroad track – a typical image-displacement result from the satellite’s sensor, Schaefer said.

Adding the second satellite




corrects




for this




.
“With the two satellites in orbit we estimate we will be able to give an 85 percent detection probability for a boat measuring 10 square meters with arbitrary speed and direction,” Schaefer said. “This is a very small boat, and the detection probability increases with larger objects.”











JSAT Chooses Ariane 5 To Loft Replacement Satellite



JSAT Corp. of Japan will launch its JCSAT-12 telecommunications satellite aboard a European Ariane 5 rocket in mid-2009 under a contract announced by Tokyo-based JSAT




Sept. 19. The satellite, being built




by Lockheed Martin Commercial Space Systems, will replace the identical JCSAT-11 satellite lost in the Sept. 5 failure of a Russian Proton-M rocket.



JSAT’s selection of an Ariane 5 launcher so soon after the loss of the JCSAT-11 satellite reflects the current tightness in the commercial-launch market, where demand




in 2008 and 2009, and perhaps into 2010, exceeds the current supply of




available vehicles.



In a separate announcement, JSAT said it had reached agreement with Broadcasting Satellite System Corp. (BSAT) of Tokyo to jointly procure and launch a telecommunications satellite into Japan’s 110 degrees east longitude orbital slot for




television broadcasting and other




telecommunications services. The satellite, which has not yet been ordered, will be launched in 2011, JSAT said.

The decision follows a July ruling




by Japan’s Ministry of Internal Affairs and Communications




ending the ban on satellites providing both fixed




and TV broadcast satellite services.



Japan’s Sky Perfect Communications Inc., a sister company to JSAT Corp. that




has 420,000 satellite-television subscribers using the JCSAT-110 satellite and forecasts that demand will continue to grow, will be the principal customer of the new satellite, JSAT said.









Nobel Winning Physicist Blasts Human Spaceflight




A Nobel Laureate issued a scathing critique Sept. 18 of NASA’s manned spaceflight program and questioned the scientific usefulness of the international space station.

“The international space station is an orbital turkey,” said Steven Weinberg, a particle physicist at the University of Texas at Austin and a co-recipient of the 1979 Nobel Prize in physics. “No important science has come out of it. I could almost say no science has come out of it. And I would go beyond that and say that the whole manned spaceflight program, which is so enormously expensive, has produced nothing of scientific value.”



Weinberg made the comments while speaking at a dark energy workshop at the Space Telescope Science Institute in Baltimore. While praising NASA’s robotic missions like the Mars Exploration Rovers, Weinberg said the manned part of the space program has contributed essentially nothing to science.

“Human beings don’t serve any useful function in space,” Weinberg said in an interview. “They radiate heat, they’re very expensive to keep alive and unlike robotic missions, they have a natural desire to come back, so that anything involving human beings is enormously expensive.”







Weinberg pointed to NASA’s treatment of its Beyond Einstein program as an example of the agency’s misplaced priorities. Beyond Einstein consists of five proposed space missions designed to build upon and expand Albert Einstein’s General Theory of Relativity.



“Only one of them is slated to go ahead, and given NASA’s record, if we suddenly run into extra expenses in the manned spaceflight program, that will be put on the back burner, just as has been done time and time again by NASA,” Weinberg said. A recent report by the National Research Council concluded that the Joint Dark Energy Mission




– designed to investigate a mysterious force




scientists think is accelerating the expansion of the universe – is the only Beyond Einstein mission ready to begin construction.



“All the others have been put on the back burner,” Weinberg said. “This is at the same time that NASA’s budget is increasing, with the increase being driven by what I see on the part of the president and the administrators of NASA as an infantile fixation on putting people into space, which has little or no scientific value.”




Riverside Technology To Support NOAA Satellites






The U.S. National Oceanic and Atmosph


eric Administration (NOAA) awarded a contract potentially




worth




$115 million




to Riverside Technology of Fort Collins, Colo., to provide technical




and




engineering support to the




agency’s weather satellite programs




, according to a NOAA news release dated Sept. 18.

The contract has a one-year base worth $16.3 million, plus four option years. Riverside will support




operation of NOAA’s




current polar- and geostationary-orbiting satellites, as well as the agency’s




program offices for




next-generation systems, according to the news release.





White House Seals End of GPS Selective Availability






The Pentagon will remove once and for all the capability to deliberately degrade civilian signals from its




GPS satellite navigation system




, according to a White House news release dated Sept. 18.

The news release said




the decision is designed to allay




concerns among




civilian GPS users around the world that their




signals could be disrupted, even though the Pentagon stopped using the so-called Selective Availability capability in May 2000.

“This decision reflects the United States




[sic] strong commitment to users of GPS that this free global utility can be counted on to support peaceful civil activities around the world,”




the




news release said.

U.S. Air Force Lt. Gen. Mike Hamel, commander of the Air Force Space and Missile Systems Center, told reporters




Sept. 19




that the decision would not affect the design of




the next-generation




GPS system




, known as GPS 3. The




Air Force had not planned to include the Selective Availability capability on that system, he said




.






The Air Force believes









the secure M-Code military signal aboard




GPS 3 and predecessor systems obviates the need for Selective Availability by allowing the military to surgically deny




GPS access in specific areas of concern, Hamel said. Selective Availability degraded civil GPS signals on a global scale.









WIN-T Contract Add-On Worth Nearly $1 Billion




The U.S. Army awarded a team of General Dynamics C4 Systems




and Lockheed Martin Mission Systems




a contract modification worth




up to $921 million to continue working on the a mobile satellite communications terminal known as




Warfighter
Information Network-Tactical (WIN-T),




General Dynamics said in a Sept. 18 press release




.

The contract is for the second and third phases of the WIN-T program, which the Army restructured and accelerated in June. The first phase, formerly known as the Joint Network Node-Network




, began in 2004 and




seeks




to enhance current networking and communications capabilities




in Iraq and Afghanistan.

For the $126 million second phase, the General Dynamics-




Lockheed Martin team will deliver a mobile broadband networking capability scheduled to begin operating




in 2009. The third phase, valued at $795 million, is for continued network capacity and security development and will address the size, weight, power and cooling demands for integrating the system into Future Combat Systems vehicles.























SAIC Wins Extension of Marshall Support Deal





NASA has extended a contract with




Science Applications International Corp. (SAIC) of San Diego to provide information technology services to the agency’s




Marshall Space Flight Center in Huntsville, Ala., SAIC said in a Sept. 17 press release.

The cost-plus-award-fee contract for the Unified NASA Information Technology Services, originally awarded in January 2004, with a three-year base,




now is slated to run through




Dec. 31, 2008. The current contract extension is the second of two one-year options.








The $205.9 million extension




raises the overall contract value to about $956 million, the release said.

Besides Marshall, SAIC also will provide information technology services to all NASA




centers, the Gagarin Cosmonaut Training Center in Star City, Russia and Russia’s BaikonurCosmodrome in Kazakhstan




.











China Launches Satellite Built Jointly With Brazil



The third in a series of optical Earth observation satellites developed jointly by the Brazilian and Chinese space agencies was successfully launched Sept. 19 aboard a Chinese Long March 4B rocket




from the Taiyuan Satellite Launch Center in Shanxi Province.

Brazil’s space agency, INPE, said it had picked up the first signals from the satellite, called CBERS-2B, later that day.

The 1,452-kilogram CBERS-2B is expected to operate in a near-circular sun-synchronous polar low Earth orbit of about 750 kilometers in altitude for two years. It follows the CBERS-1 and CBERS-2 spacecraft launched in 1999 and 2003, respectively.

The two nations




already have begun development of two more CBERS satellites that will feature a higher level of Brazilian industry participation in the development of the on




board cameras. Opts Electronics of Sao Carlos is the prime contractor to INPE for the future satellite




cameras.


USAF Completes GPS




Interim Ground System






The U.S. Air Force completed




the replacement Sept. 14 of the ground segment used to control the GPS satellite navigation system, the service




announced in a Sept. 17 press release.

The control segment determines the orbital position of GPS satellites and keeps the system operational. The new control segment, called the Architecture Evolution Plan (AEP), replaces the legacy system that has been in use since the 1970s. The upgrade is intended to increase efficiency and provide a foundation for the next-generation of GPS satellites.



The control segment consists of a




master




control




station at Schriever Air Force Base, Colo.,




a backup station




in Gaithersburg, Md.,




six monitoring stations and four ground antennas




positioned across the globe. The transition to the AEP was supposed take place more than five years ago but was delayed due to development issues and changing system requirements.



The AEP will control the current GPS satellites from the ground until the next-generation GPS 3 is operational. GPS 3 will be controlled by a new ground system, the Operational Control Segment, which is scheduled to become operational in 2011. The first GPS 3 satellites are slated to begin launching by 2013.