SSTL congratulates the EU, ESA and Astrium on the successful launch of the two first in-orbit validation (IOV) satellites, which marks a critical step for the Galileo system.

Galileo is the upcoming European satellite navigation system, equivalent to the American Global Positioning System (GPS). Galileo will start operating in 2014 as a free consumer navigation service, with more specialised services to be rolled out until 2020, when it’s planned to be fully operational

Launched by a Russian Soyuz rocket from the base in French Guiana on Friday 21 October 07:30 local time (11:30 BST), the satellites are now in their 23,000km orbit above Earth.



Friday’s launch is the beginning of the deployment of the operational system, with two further satellites of a similar design to be launched next. A further fourteen satellites being manufactured by the OHB / SSTL team will begin launching in 2012.

To find out more on Friday’s launch, read this BBC News online article

Following weeks of rigorous launch preparations, both NigeriaSat-2 and NigeriaSat-X satellites took off at 7:12 GMT on 17th August and are now in orbit and acquiring their first imagery. We’re looking into how it all went and what’s happening next.

Days before launch all seven satellites sharing the launch were integrated and the space head module assembled. The assembly was then rolled out to the rocket silo where Russian Strategic Missile Forces were waiting for the final silo operations. Besides the mission launch team, a group from SSTL and Nigerian delegates, including SSTL Executive Chairman, Sir Martin Sweeting and NASRDA head, Dr S.O Mohammed, were onsite in Yasny for the launch. This video shows the take off from the Yasny launch base.

The launch went according to plan, and after the separation from the launch vehicle was confirmed, ground stations in Abuja and Guildford established contact with NigeriaSat-2 and NigeriaSat-X respectively. This fantastic animation shows the launch sequence, and how the satellites are detached in the correct order for their intended orbits.

Continue reading "NigeriaSat-2 and NigeriaSat-X orbiting Earth"

As the launch of NigeriaSat-2 and NigeriaSat-X grows ever closer, the final preparations are underway at the launch site in Yasny, Russia. What does it actually mean to get a satellite ready for take-off? We’ve spoken to Project Manager Andrew Carrel about the work of the mission launch team, who are busy onsite getting the satellites ready to be shot up in space.

Once unpacked from their transit case the mission launch team, consisting of engineers from SSTL and Nigeria’s NASRDA, immediately began a series of meticulous tests to make sure that the satellites had made the journey in good condition and that everything was working as it should. With no problems discovered, the team could then move on to making the final preparations and fittings.

Andrew Carrel said: “When transporting satellites such a long distance, there’s always a risk things will have changed since the tests we made at SSTL before we pack them up. We were pleased to see that everything was working absolutely fine, making the preparation work much more straightforward.”

The campaign team repeated the tests done at SSTL in the final AIT stage, testing the electrical circuits and making sure that, for example, the solar panels reacted correctly when illuminated. The satellite’s subsystems were then prepared, carefully filling up the propellant and charging the batteries in the power system. Many of these preparations can only be made in the last few days before the launch to make sure the satellite is in optimum condition. This includes removing the so called “red tag” items, such as lens caps and other protective covers, as well as fitting the so called “green tag” items, such as electrical plugs to replace tests cables.

Continue reading "Rigging NigeriaSat-2 for launch"

The European Space Agency (ESA) Proba-2 mission has entered its 2 month commissioning period following a successful launch. SSTL’s Microsatellite Gas Propulsion System is on-board the 137kg small satellite and was integrated by the satellite’s manufacturer Verhaert Space Systems.

The Microsatellite Gas Propulsion System is based upon SSTL’s heritage xenon resistojet propulsion system. Its highly cost effective design provides an enhancement over conventional cold gas propulsion.

By using the resistojet thruster to heat the exhaust gas to over 300ºC a 30% increase in efficiency is gained. The electronically controlled pressure regulation improves thrust control compared to conventional mechanically regulated propulsion systems for greater positioning control in orbit.

The warm gas propulsion system is simpler, safer and cleaner than chemical propulsion systems. This makes them ideal for launcher injection correction, constellation station keeping and acquisition and orbit height maintenance for small, low cost spacecraft.

Proba-2 is the follow-on to the highly successful Proba-1 satellite launched in 2001 that carried the Compact High Resolution Imaging Sensor (CHRIS) payload manufactured by SSTL’s Optical Payloads Group. Proba-2 will demonstrate 17 advanced satellite technologies – such as miniaturised sensors for ESA's future space probes and a highly sophisticated CCD camera with a wide angle view of about 120 degrees – while carrying a set of four science instruments to observe the Sun and study the plasma environment in orbit.

A datasheet for the SSTL Microsatellite Gas Propulsion System is available on the SSTL Website.