Inside Mission Control Guildford

Wednesday, July 6. 2011
Spacecraft operations

This week, Space Blog visited Mission Control Guildford – from which SSTL monitors and controls more than a dozen small satellites – with James Northam, head of the Ground Systems Group.

We enter the room. All is quiet, apart from the whirr of server fans. Large flat screens display the footprints of the SSTL satellites in orbit. The reason for this rather quiet control room, explains James, is that SSTL Mission Control is a “lights out” operation, taking advantage of the high degree of autonomy on board the satellites and the sophisticated ground software, written in-house and unique to SSTL, to achieve this high degree of automation.

James said: “We currently track 14 satellites from our Mission Control Centre in Guildford, that is to say following their path as they orbit the Earth. We can follow their progress on-screen as they orbit and when they come into range of one of our groundstations we can communicate with them and gather data – for example monitoring their health or recovering data from the payload.

“In addition to tracking these satellites we also control four of these satellites directly from Mission Control Guildford on behalf of our customers.”

Inside the groundstation
Inside the groundstation


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Milestone for European GNSS pathfinder GIOVE-A

Wednesday, January 12. 2011
GPS and GNSS

It’s now five years since Space Blog reported on GIOVE-A transmitting its first signals for the European GNSS system. The first validation satellite GIOVE-A, was launched in December 2005 by a Soyuz rocket from Baikonur in Kazakhstan, and is still working well five years after the satellite payload was commanded 'on' from the SSTL Mission Control Centre.

With a design lifetime of 27 months, the five-year-old has exceeded all expectations. Part of its long lifespan can be put down to design margins, though luck comes into it as well, according to GIOVE manager at ESA, Valter Alpe. The satellite has been orbiting through an exceptionally quiet time in the 11-year solar cycle, meaning it has accumulated lower radiation doses than originally anticipated.

GIOVE-A launch preparations
GIOVE-A launch preparations

GIOVE-A was built by SSTL in just 30 months and carries a prototype rubidium atomic clock designed for the European GNSS constellation. In 2008 GIOVE-A was joined by GIOVE-B, equipped with an ultra-precise passive hydrogen maser design as well as a second rubidium clock. Operational European GNSS satellites will carry both clock designs for maximum reliability.

Galileo satellite's 4th birthday today

Monday, December 28. 2009
GPS and GNSS

SSTL is celebrating the 4th anniversary of the launch of its historic GIOVE-A satellite today. As the first of the Galileo In Orbit Validation Element satellites, GIOVE-A was the first step in Europe's visionary Galileo satellite navigation programme when it was launched on December 28th 2005.

During the past 4 years, SSTL and GIOVE-A have contributed significantly to the testing and validation of technologies vital to the now imminent operational constellation of satellites. The 660 kg GIOVE-A satellite was built by SSTL for ESA in just 30 months at a cost of just 28m Euros.

SSTL CEO Dr. Matt Perkins commented

SSTL is proud of its involvement with the Galileo programme and the continuing success of GIOVE-A. This mission has clearly demonstrated the effectiveness of SSTL’s small satellite approach for the delivery of operational missions.


GIOVE-A was the first part of the in-orbit validation programme for Galileo, broadcasting the first signal to successfully secure the critical Galileo frequency filing with the International Telecommunications Union (ITU) at 17:25 GMT on the 12th January 2006. This was a significant achievement for SSTL having commissioned the necessary systems to achieve this broadcast in just 3 weeks.



On the 2nd May 2007 GIOVE-A successfully transmitted the first Galileo navigation message from space, containing the information needed by users' receivers to calculate their position using the future Galileo satellite navigation service. These signals have since been used for signal quality testing and for equipment manufacturers and the scientific community to validate prototype Galileo receivers.

Throughout the past 4 years, the satellite has provided valuable data about the Medium Earth Orbit which the Galileo constellation will occupy, helping to characterise the radiation environment and validating subsystems such as an atomic clock and the Galileo signal broadcasting payload.

In July and August this year, GIOVE-A was gradually moved to a higher orbit to ensure that it does not cross the operational Galileo constellation’s orbits when the first operation satellites are launched in 2012. The satellite has been in orbit for 21 months beyond its original 27 month mission design life and continues to provide critical data to all of the ground users experimenting with Galileo navigation signals

SSTL, together with its partner OHB-System of Bremen, Germany form the core team of one of the two consortia bidding for the operational satellites. The final proposal was delivered to ESA in November and the outcome of the evaluation process is awaited. To help improve the overall schedule the team was authorised by the EC and ESA to initiate the procurement of long lead items for the full system earlier this year. The British space pioneer looks forward to continued success supporting the European Space Agency (ESA) and the EC with the expertise it has gained and its cost effective and reliable approach to satellite and subsystem design and manufacture.

Galileo satellite progress from Paris

Thursday, June 18. 2009
GPS and GNSS

Gaileo is turning out to be a hot topic at this year's Paris Air Show. On the 15th June ESA and Arianespace signed a contract for the launch of the first four operational Galileo satellites on two Soyuz launch vehicles from Europe’s Spaceport in French Guiana. Also this week, ESA and the OHB/SSTL consortium signed a contract for sourcing long-lead items for Galileo satellites.

The Galileo In-Orbit Validation (IOV) Launch Services Contract covers the launch of the first four operational Galileo satellites using two Soyuz launch vehicles that will lift off from the Guiana Space Centre (Centre Spatial Guyanais – CSG), Europe’s Spaceport in French Guiana.

ESA Galileo IOV launch signing
Galileo IOV launch signing
ESA - S. Corvaja, 2009
This new development follows the successful launch of the GIOVE-A satellite which was built by SSTL and the GIOVE-B satellite which was to be built by the European Satellite Navigation Industries satellite consortium and ultimately completed by Astrium. Both satellites have provided a great deal of data, for example helping with with clock characterisation, Galileo signal testing and in understanding the radiation that future Galileo satellites such as the new IOV satellites can expect in Medium Earth orbit (MEO).

The signature of the IOV Launch Services Contract in Paris marks an important milestone for the Galileo programme as it progresses towards the operational deployment of the satellites of the Galileo satellite navigation system. The four IOV satellites will be placed in a circular orbit at an altitude of MEO of 23 600 km by the end of 2010. Development of the Galileo system is being carried out under a joint ESA/European Union programme.

The launch vehicle chosen to carry the four Galileo IOV satellites into orbit is the Soyuz ST-B with a Fregat MT upper stage, which has been adapted for the deployment needs of the Galileo programme. The Soyuz at CSG Programme is an ESA Programme with co-funding of Arianespace and the European Union.

Galileo operational constellation
Meanwhile, ESA and the bidder consortium led by OHB-System AG and Surrey Satellite Technology Ltd. (SSTL) have signed a contract for sourcing long-lead items for satellites for the future European Galileo navigation system in Paris the same week. The EUR 10 million contract is carried out under a program initiated and funded by the European Union.

Through this contract, OHB and SSTL are able to place orders for satellite technologies which require considerable lead times for development and sourcing ahead of the award of the actual contract for the construction of the satellites. The Galileo System customers, the European Union and the ESA, are thus ensuring that the schedule for implementation of Galileo can be maintained.

OHB and SSTL are one of two consortia bidding for the development and con-struction of 28 satellites for Galileo. By allowing two consortia to build spacecraft for this significant undertaking, ESA is ensuring that the full operational capa-bility can be put in place as soon as possible and at best value to the EU. The system is to be fully operational by 2013 following full contract signature later in 2009.