ESA: ExoMars Trace Gas Orbiter to Perform Critical Orbit Insertion Burn to Mars

ESA's Mars orbiter will perform the most critical moment in the journey so far: the orbit insertion burn.

The ExoMars Trace Gas Orbiter (TGO) will fire its engine for 134 minutes to allow the spacecraft to slow down sufficiently to be captured into Mars' orbit on Wednesday, Oct. 19.

The engine burn will be performed autonomously by TGO based on commands set by the control team at European Space Operations Center (ESOC) in Darmstadt, Germany. About 30 minutes before the burn, the orbiter will turn to point its main engine toward the direction of travel. While in this position, Earth will temporarily lose contact with the orbiter, but it will emerge from behind Mars and begin reconfiguring its radios to send a "carrier only" signal to Earth using its Low Gain Antenna.

"It will be a tense wait for everyone on ground but, all being well, it will come out of occultation on time and telling us all we need to know about the burn performance," Thomas Ornston, a spacecraft operations engineer at ESOC, said in a blog post.

"Flight Dynamics will then measure and assess the orbit the spacecraft has actually achieved and provide us final confirmation that Europe has returned to Mars."

The orbiter stopped sending status updates earlier after releasing the Schiaparelli lander on a three-day trek to the surface of Mars on Sunday, Oct. 16. ESOC officials thought that the separation had been "more violent than expected," which may have caused the break in telemetry. Ground controllers were finally able to re-establish full links with the orbiter shortly after.

"Everything is back on track," ESOC spokeswoman Jocelyne Landeau-Constantin confirmed in a statement. The orbit insertion maneuver will continue as planned to steer the orbiter off a collision course with Mars.

The European-Russian ExoMars mission is comprised of the TGO and the Schiaparelli demonstrator module, which launched from the Baikonur space center in Kazakhstan on March 14 on board a Proton rocket. The Schiaparelli lander has successfully detached from the TGO on Sunday, Oct. 16 and is ready to descend on the Red Planet's Meridiani Planum region.

The Schiaparelli module is designed to demonstrate ESA's entry, descent and landing technologies, while the TGO will study methane and other gases present in the Martian atmosphere.