In addition to its role as a central player in European Space Agency (ESA) programs, the French space agency, CNES, expects to continue building its own space-science satellites, and CNES officials said Nov. 16 the Corot astronomy satellite could be a model for those future missions.

Corot, scheduled for launch in late 2006 aboard the inaugural flight of an upgraded version of the Russian Soyuz rocket, is designed to examine the seismology of stars and to look for Earthlike planets around stars.

It will provide a broader, but less-precise, field of view than NASA’s Kepler satellite, a larger spacecraft that will stare for long periods at a single patch of the universe in hopes of finding Earthlike planets. Kepler is scheduled for launch in mid-2008.

Corot, a program that was returned to active status in 2004 after being put on hold as CNES worked through a financial crisis, is budgeted at 150 million euros ($180 million) including satellite construction and launch, ground facilities and three years of operation in orbit.

CNES is financing 60 percent of the mission, according to CNES Corot project manager Thien Lam Trong. France’s national scientific research institute, CNRS, is paying for 20 percent of Corot, with the remaining 20 percent coming from CNES’ junior partners in the mission. These include the national space agencies of Germany, Austria, Brazil, Spain and Belgium.

In a reversal of their normal relationship, ESA also is helping to fund Corot, a decision that ESA officials said they made to save the project from the scrap heap when CNES ran out of money .

Most European national governments put the majority of their space spending into the common ESA account. ESA then awards contracts based on each nation’s contribution. In the case of science missions, ESA’s 17 member nations invest automatically each year, with the amount based on each nation’s gross domestic product.

The ESA science budget is then supplemented by individual nations’ science laboratories, which finance and build ESA science satellite sensors.

Several nations, including Germany, Italy and Sweden, maintain enough budget leeway outside ESA to launch small science satellites of their own. But these are becoming more rare as space budgets tighten and most nations direct their space funding toward ESA.

That is not true of CNES and France. Under a six-year contract signed with the French government in April, CNES has been promised a stable space budget through 2010 that is evenly divided between ESA and non-ESA projects. The ESA contribution will remain flat at 685 million euros per year, while the non-ESA budget, which is 681 million euros this year, will rise by 1.5 percent per year.

Richard Bonneville, head of science projects at CNES, said the Corot mission should be viewed as one model for the way CNES expects to operate as project initiator, prime contractor and mission manager.

Bonneville said during Corot briefings here Nov. 16 that the CNES budget permits the agency to initiate one or two new science satellites in 2006. Several candidate missions are being reviewed.

“In France we intend to pursue our program of mini- and microsatellites,” Bonneville said. “Demonstrating techniques for flying satellites in formation is one of several areas we are interested in.”

Corot, which is expected to weigh 600 kilograms at launch, will use the CNES-designed Proteus satellite multimission platform built by Alcatel Alenia Space. CNES signed a contract with Alcatel Alenia Space for five Proteus satellites after the Jason-1 ocean altimetry satellite launched in 2001.

Four of those satellites have been contracted, including Corot. The three others are the Calipso cloud-monitoring satellite, which is expected to be launched in the coming weeks; the Soil Moisture and Ocean Salnity (SMOS) satellite set for launch in 2007; and the Jason-1 follow-on, called Jason-2, set for launch in mid-2008.

Corot is intended to operate from a 900-kilometer polar Earth orbit. Its launch vehicle, the Soyuz 2-1b, features a new upper stage that will be making its inaugural flight. It is expected to be the second flight of a new digital avionics fleet to be installed on a different Soyuz model to fly in mid-2006.

The Soyuz 2-1b is the vehicle model to be operated from Europe’s Guiana Space Center spaceport starting in late 2008.

The customary Soyuz commercial launch price is about $40 million. Tran declined to say exactly how much CNES is paying for the Corot launch, but he suggested the agency was getting a discount in exchange for agreeing to be the maiden-fight passenger.

“Any launcher can be cause for worry, the statistics are clear about that,” Tran said.

Peter B. de Selding was the Paris bureau chief for SpaceNews.