LE BOURGET, France—NASA and French space agency CNES have agreed to establish closer ties between the two agencies on assessing the conjunction of objects in orbit, including space debris.

The agreement, signed by CNES President Jean-Yves Le Gall and NASA Administrator Charles Bolden here June 16, aims to improve the agencies’ means and methods for orbital collision avoidance in an effort to boost the safety of satellite mission operations.

The agreement builds on cooperative accords singed in 2014 and this year between the French Ministry of Defense and U.S. Strategic Command on the exchange of orbital data concerning debris from satellites and launch vehicles.

CNES is contributing its expertise on orbital conjunction assessment and working on data-exchange procedures.

The most-recent agreement aims to strengthen cooperation between France and the U.S. in orbital conjunction assessment and assure better coordination between teams in charge of space surveillance and tracking.

NASA and the Pentagon cooperate and share responsibilities for characterizing the satellite environment, including orbital debris, using the Defense Department’s Space Surveillance Network, which tracks discrete objects as small as 2 in. (5 cm) in diameter in low Earth orbit and about 1 yard in geosynchronous orbit.

Currently, about 15,000 officially cataloged objects are orbiting the Earth, though the total number of tracked objects exceeds 21,000. Using special, ground-based sensors and inspections of returned satellite surfaces, NASA statistically determines the extent of the population for objects with less than a 4-in. diameter.

NASA has been assessing the conjunction of objects in orbit to support collision avoidance since the 1988 launch of the STS-26 space shuttle mission. Ten years later, before launching the first hardware for the International Space Station in 1998, NASA and the Defense Department jointly developed and implemented a more sophisticated and higher fidelity conjunction assessment process for human spaceflight missions.

In 2005, NASA implemented a similar process for certain robotic spacecraft, including Earth observation satellites in low Earth orbit and the Tracking and Data Relay Satellite System in geosynchronous orbit. In 2007, NASA extended the conjunction assessment process to all NASA-maneuverable spacecraft in low Earth orbit and within 124 mi. (200 km) of geosynchronous orbit.