A team of teams like never before: rehearsing a unique launch at ESA mission control

On 15 September, two spacecraft will leave Earth together aboard the same launcher from Europe's spaceport in Kourou: FLEX, ESA's photosynthesis mission, and Sentinel-3C, Copernicus' newest satellite monitoring Earth's oceans, land, ice and atmosphere. At ESA's European Space Operations Centre (ESOC), two independent mission teams are preparing to operate their spacecraft in parallel in a closely coordinated effort, rehearsing side by side not only for their own missions but also for the moments when the two operations intersect.

Preparing a spacecraft for its first days in orbit normally requires a large team of spacecraft operations engineers, flight dynamics specialists, ground operators, software experts and project teams that supported the satellite's design, production and testing, backed by control rooms, ground stations and communications networks. For this launch, ESA is preparing all of that for two missions at once. Once in space, FLEX and Sentinel-3C will operate in closely related orbits, creating additional operational considerations during launch and early operations.

"Launching two satellites is not the difficult part. We've done similar things before, such as ESA's Herschel and Planck missions in 2009, but those were managed by a combined team," says Franco Marchese, ESA's Flight Operations Director for the Sentinel-3C launch and early orbit phase (LEOP). "What makes this launch different is that we have two teams operating in parallel and that the satellites fly in basically the same orbit. That's the real challenge." He adds that ESOC is one of the few mission control centres in the world that can do this.

Each launch campaign relies on a "team of teams" of specialists across many disciplines working as one operational community. Isabelle Dauvin, a Spacecraft Operations Manager for ESA's FLEX mission, and Libe Jauregui, ESA's Flight Dynamics Manager for Sentinel-3C, describe the shared sense of purpose: "During a LEOP, everyone is trying to meet a common goal. You really feel it." For Sentinel-3C and FLEX, two complete mission teams are preparing to operate side by side, each with its own flight control team, ground stations operations team, flight dynamics team and project teams focused on their respective spacecraft.

While the two missions' teams prepare and operate independently, their work intersects at key points: some resources and support teams are shared, and certain activities require close coordination between the missions. This means preparing not only for each mission's individual needs, but also for situations in which both teams may need to act, respond or access shared resources at the same time.