Pleiades

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A payload section during the second Soyuz rocket mission launch from Kourou in December 2011. Credit: Arianespace

Launch

A second Soyuz to fly from Kourou lifts off on Friday, Dec. 16, 2011. Credit: Arianespace

Pleiades

An artist rendering of the Pleiades 1 satellite, which promised to provide images of the Earth surface with a resolution of 70 centimeters. Credit: Arianespace

Elisa

An artist rendering of a quartet of ELISA satellites designed for electronic intelligence. Credit: Arianespace

Above: A mission scenario of the second Soyuz rocket launch from Kourou on Dec. 16, 2011.

Previous chapter: Soyuz in Kourou

Arianespace confirmed Soyuz’ mission flexibility in operations from the space center in Kourou with a successful launch that placed six satellites into Sun-synchronous orbit.

Departing precisely at the planned liftoff time on Dec. 17, 2011, at 11:03:08 p.m. in French Guiana, the Soyuz-ST-A/Fregat performed a 3-hour, 26-minute flight to deploy its payload of the French Pléiades 1 and Chilean SSOT satellites for civilian and defense image gathering, along with four French ELISA micro-satellite demonstrators for defense-related electronic intelligence gathering (ELINT).

This was Arianespace’s second mission with the Russian-built medium-lift workhorse launcher performed from Kourou, and it occurred less than two months after Soyuz’ historic maiden flight from its new launch pad in French Guiana on October 21, 2011.

Designated Flight VS02 in Arianespace launcher family numbering system, the Dec. 16 mission involved four burns of Soyuz’ Fregat upper stage, which enabled the six satellites to be released for operations at altitudes ranging from 610 to 700 kilometers. Using a new purpose-built payload dispenser developed for Arianespace’s Soyuz missions, the deployment sequence began with the release of Pléiades 1. It was followed by the simultaneous separation of all four ELISA satellites, and the mission was completed with the deployment of SSOT, which occurred three hours, 26 minutes after liftoff.

The Soyuz lift performance was an estimated 2,190 kilograms, which includes approximately 1,400 kilograms for the Pléiades 1, ELISA and SSOT satellites, along with the weight of its payload dispenser and integration hardware. This was the 1,781st flight of the Soyuz launcher family, which ushered in the space age and continues to demonstrate its reliability and robustness in both unmanned and manned missions.

Pléiades 1 weighed 970 kg. at launch and will provide military and civilian users with very high resolution optical satellite imagery from a 700-km. orbit, offering 50-cm. resolution imaging products at a coverage swath width of 20 km. Built by prime contractor Astrium for the French CNES space agency, Pléiades 1 is a compact, hexagonal-shaped spacecraft optimized for operational agility and image location accuracy.

The Soyuz mission’s four ELISA micro-satellites are part of a joint demonstrator program involving the French DGA defense procurement organization and the country’s CNES space agency, with these spacecraft developed in a partnership of Astrium and Thales Airborne Systems. Weighing 120 kg. each, they have an operational design life of more than three years.

Chile’s SSOT (Sistema satelital de Observación de la Tierra) is a dual-role military/civilian optical satellite that weighed 117 kilograms at launch, and is designed for such missions as mapping, agricultural monitoring, and the management of natural resources, disasters and risks. Built by Astrium for the Chilean armed forces, SSOT is based on the same CNES-conceived spacecraft platform as the ELISA satellites.

Following the successful launch on December 16, Arianespace planned another Soyuz mission on December 28 from Baikonur Cosmodrome in Kazakhstan, while preparations were continuing in Kourou for the new lightweight Vega’s inaugural liftoff, as well as for the next heavy-lift Ariane 5 flight.

The upcoming Baikonur Cosmodrome launch, referred to as Flight ST24, will be performed on Arianespace’s behalf by its Starsem affiliate, marking the third such Soyuz mission to carry a cluster of six Globalstar second-generation satellites.

Arianespace’s activities in 2012 included the initial Vega to be launched from French Guiana, which was taking shape with its solid propellant first, second and third stages now stacked on the ELA-1 launch pad. In the next several days, Vega’s AVUM liquid-propellant upper stage was to be moved to the pad and installed atop the launcher. Integration of the “upper composite,” consisting of the launcher’s payload and protective fairing, was planned for January 2012, followed by final verifications of the fully integrated launcher and the countdown rehearsal.

This introductory Vega mission – designated VV01 – is anticipated in the January-February timeframe, and will carry Italy’s LARES laser relativity satellite, along with the ALMASat-1 spacecraft from European universities and several small cubesat platforms.

Separately, the no. 3 Automated Transfer Vehicle (ATV) for servicing of the International Space Station was scheduled for a March 9 liftoff from ELA-3 launch pad in French Guiana on an Ariane 5. This flight’s launcher has now been declared ready for the Spaceport handover to Arianespace by industrial prime contractor Astrium. It will be the 205th mission with an Ariane family vehicle, and is designated VA205 in Arianespace’s numbering sequence.

The ATV’s two major components – its Integrated Cargo Carrier and the Service Module – were mated this week in the S5 payload preparation building at the Spaceport, marking a major milestone in preparations for the resupply spacecraft’s liftoff.

Operationally, Ariane 5 lofted eight large geostationary telecommunications satellites from French Guiana during the year – representing one-half of all such payloads orbited worldwide in 2011 – along with the no. 2 Automated Transfer Vehicle. Added to this are the two Galileo navigation spacecraft carried by Soyuz’ no. 1 flight in October and the six payloads on tonight’s Soyuz mission from Kourou, which was to be completed by the six Globalstar platforms scheduled for later this month from Baikonur Cosmodrome.

From the business point of view, Arianespace by signing in 2011 new launch contracts for 10 geostationary satellites and the BepiColombo deep space probe to Mercury -- providing spacecraft to fill the equivalent of six Ariane 5 flights, along with payloads for one Soyuz mission from French Guiana and for the Vega’s first two commercial launches from Kourou.

Page author: Anatoly Zak; Last update: December 21, 2011