Soyuz ST-B booster sends two more Galileo navigation satellites to orbit
European Launch Service Provider Arianespace launched two more Galileo navigational satellites (known as “Andriana” and “Liene”) Thursday, Dec. 17, 2015. The firm used a Soyuz ST-B booster to lift the FM08 and FM09 satellites off the launch pad located at the Spaceport in Kourou, French Guiana, at 6:51 a.m. EST (11:51 GMT).
When all is said and done, there will be some 30 Galileo satellites on orbit and will provide Europe with a system comparable to the U.S.’ Global Positioning System.
The launch vehicle was rolled out and installed on the launch pad on Monday, Dec. 14. It was erected to the vertical orientation, where it was suspended in place by four large support arms, followed by the transport rail car’s withdrawal. Next, the rocket’s “upper composite” – composed of the two Galileo spacecraft and their dispenser system, the Fregat upper stage, and payload fairing – was attached to the launcher.
The Soyuz ST-B rocket, carrying a total payload of 1.6 metric tons, started its short vertical ascent followed by pitching and rolling onto a northeastern course. The launch vehicle’s boosters were jettisoned nearly two minutes after liftoff. The payload fairing separated about one and a half minutes later. Shortly after, the second stage was ignited continuing the flight for approximately one minute and 19 seconds until the separation. The third stage took control over the mission, flying for nearly five minutes and was then detached from the Fregat upper stage. Fregat started its 3-hour flight to deploy Galileo satellites into targeted orbit. Finally, three hours and 48 minutes after the launch, the duo of spacecraft were injected into a medium-Earth orbit (MEO) at an altitude of 14,430 miles (23,222 km), inclined 54.9 degrees.
“As a benchmark launch services partner in the Galileo program, Arianespace upholds its commitment to guaranteed independent access to space for Europe. Today’s launch, the third this year for Galileo and the eighth on behalf of European governments, marks a further step towards European independence in satellite navigation. With 12 satellites now in the Galileo constellation, the system could deliver its initial services by the end of 2016,” Stéphane Israël, Chairman and CEO of Arianespace said, shortly after the Galileo satellites were injected into orbit.
The flight was designated VS13 in Arianespace’s numbering system. It was the 13th Soyuz launch overall from the Guiana Space Center.
“With today’s launch, Europe has doubled the number of its Galileo satellites in orbit in just nine months,” commented Jan Woerner, Director General of ESA. “Along with the ground stations put in place around the globe, this brings Galileo’s completion within reach. Initial Galileo services are scheduled to begin within next year, which proves the importance of this wise investment.”
The Galileo satellites are built by prime contractor OHB System in Bremen, Germany. The payload for each satellite is supplied by UK-based Surrey Satellite Technology Ltd (SSTL). The satellites weigh 1,580 lbs. (717 kg) each and their dimensions are 8.85 by 3.94 by 3.61 feet (2.7 by 1.2 by 1.1 m). They consume 1,900 W of onboard power and are designed to operate for more than 12 years.
“Following the successful initialization, a stable connection with the two satellites has been established, and the solar panels have been unfolded and correctly aligned towards the Sun. All the previously launched Galileo FOC satellites have already demonstrated their full functional and performance capabilities. Our satellite production in Bremen and environmental tests in Noordwijk are proceeding according to schedule,” said Ingo Engeln, OHB System’s executive board member.
The Galileo spacecraft feature four clocks. They provide the precise timing solutions needed for the calculation of the time delay from the moment the signal is sent and the arrival at the receiver that allows the calculation of the distance to the satellite.
Thanks to a greater number of Galileo signals, the new satellite clock design, and improved corrections for ionospheric effects, positions computed with Galileo satellites will be more accurate.
The Galileo program is Europe’s initiative for a state-of-the-art global satellite navigation system, providing a highly accurate global positioning service under civilian control. Galileo will provide Europe with independence in satellite navigation but will also be inter-operable with GPS and GLONASS, the two other global satellite navigation systems.
ESA has been working for the better part of a decade to field its own satellite navigation system. In fact, this December’s launch marked the 10th anniversary of the launch of Europe’s GIOVE-A spacecraft – Europe’s first navigational satellite. That flight took place on December 28, 2005. GIOVE-A not only served as a technology demonstrator – but also to secure the frequencies that would be used by the Galileo constellation.
GIOVE-A also worked to provide researchers with a better understanding of the medium-altitude orbit environment.
“The excellent performance of these satellites, as measured on the ground, allows Europe to join the club of the worldwide providers of satellite navigation services,” said Didier Faivre, ESA’s Director of Galileo and Navigation-related Activities via a release. “Production, testing and launch of the remaining satellites are now proceeding on a steady basis according to plan.”
ESA co-funded the development and on-orbit validation phases of Galileo along with the European Commission. ESA has been working to, essentially, “walk in” the Galileo constellation, first fielding what the agency has described as a mini-constellation of four satellites.
The next mission for the Galileo program is planned for the second half of 2016, using the first Ariane 5 ES, which will carry four satellites.
“Then, after the summer break in 2016, the tempo of deployment will increase further with the first of three customized Ariane 5 launchers that will carry four rather than two satellites into orbit each time,” Faivre said.
“I think now we can honestly say that Galileo is a success,” said Elżbieta Bieńkowska, the European Union Commissioner for Internal Market, Industry, Entrepreneurship, and SMEs. “Because never before has Europe collectively invested its know-how and resources in a single project. Now we are there and we have to continue.”
In 2017 and 2018, one Soyuz and two Ariane 5 ES missions will expand the constellation to 26 satellites out of a planned total of 30.
The Soyuz ST-B version currently offered by Arianespace is a four-stage launch vehicle: four boosters (first stage), a central core (second stage), a third stage, and the restartable Fregat upper stage (fourth stage). It also includes a payload adapter/dispenser and fairing.
The four cylindrical-conical boosters are assembled around the central core. The booster’s RD-107A engines are powered by liquid oxygen and kerosene, the same propellants used on each of the lower three stages.
The central core is similar in construction to the four boosters, with a distinctive shape to accommodate the boosters. A stiffening ring is located at the interface between the boosters and the core. This stage is fitted with an RD-108A engine, also comprising four combustion chambers and four nozzles. It also has four vernier thrusters, used for three-axis flight control once the boosters have separated.
The third stage is linked to the central core by a latticework structure. Ignition of the third stage’s engine occurs approximately two seconds before shutdown of the central core engine. It uses one RD-0124 engine.
The Fregat upper stage is an autonomous and flexible stage that is designed to operate as an orbital vehicle. It extends the capability of the Soyuz launcher, now covering a full range of orbits. Fregat has its own guidance, navigation, attitude control, tracking, and telemetry systems. The stage’s engine uses storable propellants – UDMH (unsymmetrical dimethyl hydrazine) and NTO (nitrogen tetroxide) – and can be restarted up to 20 times in flight, thus enabling it to carry out complex missions. It can provide the customer with 3-axis or spin stabilization of their spacecraft. The Fregat upper stage is encapsulated in a fairing with the payload and a payload adapter.
The first launch of the Soyuz ST-B was conducted on Oct. 2011, lofting the first two Galileo IOV satellites.
Video Courtesy of Arianespace
Jason Rhian spent several years honing his skills with internships at NASA, the National Space Society and other organizations. He has provided content for outlets such as: Aviation Week & Space Technology, Space.com, The Mars Society and Universe Today.