Did Russian Roulette Nearly Claim ExoMars?

Artist’s impression depicting the separation of the ExoMars 2016 entry, descent and landing demonstrator module, named Schiaparelli, from the Trace Gas Orbiter, and heading for Mars. (Credit: ESA/ATG Medialab)

The Russian roulette that is that nation’s launch industry nearly claimed Europe’s most ambitious planetary mission earlier this month.

That’s according to a report from Anatoly Zak in Popular Mechanics. Zak says there is evidence of an anomaly that sent pieces of the Proton launcher’s Briz-M upper stage into interplanetary space along with ESA’s ExoMars spacecraft.

Shortly after the separation between ExoMars and the spent Briz-M, the probe called home, and the ground control center in Darmstadt, Germany, confirmed the mission was on a path to Mars. However, astronomers tracking the flight soon spotted a cloud of debris accompanying ExoMars in space. As many as six large pieces of space junk appeared on the photos taken by the OASI observatory in Brazil.

This was strange. For one thing, the Briz-M was supposed to separate cleanly in one large piece without producing any additional fragments. Secondly, and more importantly, after the separation the space tug was programmed to fire twice to propel itself to a safe disposal orbit as far away from its former cargo as possible. The resulting “graveyard” trajectory would ensure that the “blind and deaf” space tug, now drifting through interplanetary space, would not come anywhere near Mars, where it could contaminate the planet’s pristine environment with Earth’s bugs. (Unlike Mars landers, rocket stages are not sterilized in accordance with strict international standards.)

According to sources in the Russian space industry, the first of Briz-M’s two collision-avoidance maneuvers was to last around 12 seconds. Once it was a safe distance from ExoMars, the rocket stage would fire again, this time for around 1.5 minutes, until the engine consumed all the remaining explosive propellant aboard. Upon completion of the second maneuver, valves would open to vent the high-pressure gas used to force propellant into the engines.

That’s what’s supposed to happen. The initial info available to Russian tracking experts after the launch of ExoMars indicated that Briz-M had worked as planned. But the latest tracking photos indicate that something happened before the spacecraft had had a chance to go into its graveyard orbit.

In an update published on Wednesday, ESA said ExoMars is performing “flawlessly.”

“The ESA–Roscosmos ExoMars Trace Gas Orbiter (TGO) and the Schiaparelli entry, descent and landing demonstrator are well on their way following the 14 March launch from Baikonur Cosmodrome in Kazakhstan,” the agency said.

Russia has suffered through a long string of launch failures dating back near seven years. Many of the failures are traced to the Proton rocket and the Briz-M upper stage, which are both produced by the Khrunichev State Research and Production Space Center, which has experienced serious quality control problems.