PARIS — The German-Russian Eurockot Launch Services joint venture announced Feb. 9 it will launch two European environment-monitoring satellites aboard Russian Rockot vehicles under contracts with the European Space Agency (ESA).

The launches, from northern Russia’s Plesetsk Cosmodrome, will carry the Sentinel 2A and Sentinel 3A satellites into polar low Earth orbit, with the first of the two launches to occur no earlier than late 2013.

The 19-nation ESA is managing development of the Sentinel series of Earth observation satellites as part of the Global Monitoring for Environment and Security (GMES) program funded jointly with the European Commission.

While the commission remains uncertain of how to finance its share of future GMES investment beyond 2013, ESA for now is proceeding as if GMES’s future is assured. The agency previously has threatened that it will cancel its Sentinel launches if the commission does not assure post-2013 GMES funding.

ESA hopes eventually to use the Vega small-satellite launcher for most of its Earth observation and science satellites. But with Vega’s entry into operation behind schedule, the agency is continuing to contract with Eurockot to hedge against future Vega delays.

Vega is scheduled to make its inaugural flight Feb. 13 from Europe’s Guiana Space Center spaceport in South America. The Arianespace launch consortium of Evry, France, has already booked two commercial launches for Vega. Both contracts are with ESA, for the Sentinel 2B and 3B satellites.

Eurockot Sales Director Peter Freeborn said the Russian government has told the company that Rockot vehicles, based on Russia’s SS-19 ballistic missile, will be available at least until 2018.

In a Feb. 9 interview, Freeborn said Rockot is scheduled to launch five times in 2012 — four Russian government launches and one launch for ESA, of the Swarm environmental satellites.

With the two Sentinel contracts, Eurockot’s backlog now consists of four launches, all for ESA, including one of a yet-to-be-selected satellite in 2014. Two science spacecraft, called Lisa Pathfinder and Aeolus, are the prime contenders.

Eurockot is 51 percent owned by Astrium, the space division of Europe’s EADS aerospace giant, and 49 percent by Khrunichev State Research and Production Space Center of Moscow, one of Russia’s biggest space-hardware manufacturers.

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