PARIS — Astrium Space Transportation on July 7 announced it will lead a consortium of companies to produce designs and cost estimates for a next-generation rocket under a 15-month contract with the European Space Agency (ESA) valued at 10 million euros ($12.6 million).

Les Mureaux, France-based Astrium Space Transportation will be financing 1.5 million euros of the contract with funds from the industrial consortium, with the 18-nation ESA paying the rest.

ESA governments are weighing whether to finance development of a successor to the current Ariane 5 rocket at their next ministerial conference, scheduled for 2012. The new rocket would be ready for service around 2025.

Multiple designs for a two- or three-stage rocket with cryogenic, solid-fueled and methane/oxygen main stages will be studied not only for their performance, but also for their long-term operating costs.

While no decision has been made, the early design work will focus on a vehicle that would add or subtract strap-on boosters to lift satellites weighing as little as 3,000 kilograms and as much as 7,500 kilograms into geostationary transfer orbit, the destination of most telecommunications satellites.

The next-generation launcher would, under the preliminary designs being investigated, launch one satellite at a time into geostationary orbit, not two, as typically is the case with the current Ariane 5.

European government officials have said the Ariane 5 successor should be able to replace both the Ariane 5 and the medium-lift Soyuz rocket, a European version of which is scheduled to operate from Europe’s Guiana Space Center starting in late 2010 or early 2011. The Soyuz is capable of placing a 3,000-kilogram telecommunications satellite into geostationary transfer orbit from the equatorial French Guiana facility.

The successor rocket would permit European governments to launch civil and military Earth observation satellites weighing up to 4,000 kilograms on a vehicle made in Europe, instead of relying on Soyuz.

Government officials have made clear that whatever design is agreed to must meet annual operating-cost criteria and not just satisfy performance requirements.

The study will “highlight competitiveness factors to reach around 2025 — reliability, availability and minimization of costs, particularly operating costs,” Astrium said in a statement. Companies from the nine nations that participated in the development of the Ariane 5 are in the Astrium-led consortium.

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