ExoMars team has long wait to confirm launch success
Artist’s concept of the Proton rocket’s payload fairing releasing in flight, revealing the ExoMars spacecraft. Credit: ESA–David Ducros
It will take more than 12 hours from liftoff of the European Space Agency’s ExoMars Trace Gas Orbiter until engineers verify the mission is on track for Mars after a series of critical in-space maneuvers by the Proton rocket’s Breeze M upper stage.
The Proton/Breeze M launcher has never sent a mission to Mars before, but while the flight profile is different most of the rocket’s missions, the ExoMars launch will not set records in mission duration or complexity.
The 191-foot-tall (58-meter) Russian-built rocket is counting down to launch at 0931:42 GMT (5:31:42 a.m. EST) on Europe’s most ambitious mission ever to another planet.
While the marathon rocket mission is not unusual to commercial communications satellite operators who often use the Proton/Breeze M, it is new to scientists and engineers mounting a Mars mission.
Jorge Vago, an Argentine-born researcher, leads the science aspects of the ExoMars mission for the European Space Agency.
He spoke with Spaceflight Now on the eve of the launch of the ExoMars Trace Gas Orbiter and the Schiaparelli lander, a tandem craft that ranks among the most massive probes ever dispatched to the red planet.
“It’s a mixture of being happy that we’ve gotten to this moment, and I’m also nervous, of course,” Vago said in an interview.
Packaged atop the Proton rocket are the ExoMars Trace Gas Orbiter, a platform designed to map the prevalence of methane in the Martian atmosphere, and the Schiaparelli lander, a stationary module that will make an automated touchdown on the red planet Oct. 19.
“A launch is always a tricky affair, and in particular the trajectory injection that requires four burns of the Breeze upper stage over a 10-hour period,” Vago said. “Each one of those has to work just fine to put us on the right trajectory to get to Mars.”
The Proton rocket will pitch east-northeast from the Baikonur Cosmodrome with the ExoMars spacecraft, soaring on more than 2 million pounds of thrust from six first stage RD-276 engines.The major events of the ExoMars launch are listed below:
T+00:00:00 — Liftoff
T+00:02:00 — First Stage Separation/Second Stage Ignition
T+00:05:27 — Second Stage Separation/Third Stage Ignition
T+00:05:47 — Payload Fairing Jettison
T+00:09:42 — Third Stage Separation from Breeze M
T+00:10:16 — First Breeze M Ignition
T+01:38:04 — Second Breeze M Ignition
T+03:52:16 — Third Breeze M Ignition
T+10:16:10 — Fourth Breeze M Ignition
T+10:41:18 — ExoMars Separation
“It’s not just a case of watching the launch, and then saying, ‘Yippee, everything went OK,'” Vago said. “We have and sit and bite our nails for another 10 hours.”
The Breeze M main engine firings will propel the ExoMars payload higher and faster on the way to Mars, building up enough energy to escape the bonds of Earth’s gravity.
Deployment of the 9,550-pound (4,332-kilogram) ExoMars spacecraft from the Breeze M upper stage is set for 2012 GMT (4:12 p.m. EDT).
“Shortly thereafter, we will deploy the solar panels,” Vago said. “Once that has happened, and we know that the Breeze upper stage worked OK, then I think we can pop the cork.”
Ground controllers at the European Space Operations Center in Darmstadt, Germany, expect to receive signals from the Trace Gas Orbiter around 2128 GMT (5:28 p.m. EDT) via a ground station in Malindi, Kenya. The communications pass will give engineers confirmation the spacecraft is healthy following launch, and officials also hope to verify the extension of the orbiter’s power-generating solar panels.
Often used to propel communications satellites into high-altitude orbits thousands of miles above Earth, the Proton/Breeze M combo has flown 87 times since 2001. The Proton’s core booster has been flying since 1965, amassing 410 missions launching commercial and Russian military satellites.
But the launcher’s track record in recent years has been spotty, at best, with six failures of the Proton rocket or its Breeze M upper stage logged in 49 flights since December 2010. The Proton/Breeze M has a run of six straight successes since its last mishap in May 2015.
Two of the recent failures were blamed on a design flaw in the Proton’s third stage — a weakness that Russian officials say has now been corrected — and investigators identified quality control issues for other in-flight anomalies.
“ESA got a report of the last failure and all the measurements they have taken, and they are strongly committed to not allowing this to happen again,” said Walter Cugno, ExoMars program manager at Thales Alenia Space, the mission’s primary European contractor.
Russia has a star-crossed history with launches of Mars missions, with the last two attempts never making it out of low Earth orbit.
European space officials switched the ExoMars launches to Russian Proton rockets after NASA withdrew from the program in 2012 due to funding restrictions within the agency’s planetary science budget.
NASA originally signed up to launch the 2016 and 2018 missions aboard Atlas 5 rockets from Cape Canaveral.
Email the author.
Follow Stephen Clark on Twitter: @StephenClark1.