The European Space Agency (ESA) this week is poised to reach a milestone on its groundbreaking ExoMars mission to Mars. On October 19, the agency expects to land its Schiaparelli landing module on the red planet as part of a technology demonstration and data collecting mission.
The space agency already completed a critical stage of the mission on October 16 when the Schiaparelli module separated from the ExoMars Trace Gas Orbiter (TGO) and began its descent to the surface of Mars. The module will descend for three days until it encounters Mars’ outer atmosphere, and the final descent and landing will then take under six minutes to complete.
ExoMars is a collaborative effort between the ESA and the Russian Roscosmos space agency. The mission involve two vehicles — the Trace Gas Orbiter (TGO), which navigated to the outer edge of the Mars atmosphere, and the Schiaparelli technology demonstration vehicle, which is slated to land on the surface for data collection. This cone-shaped module was attached to the TGO and began its seven-month journey to Mars following a successful launch on March 14.
The TGO and Schiaparelli module traveled through space under the guidance of the ESA with the TGO providing all the power and communications for this first stage of the mission. When the TGO reached Mars orbit on October 16, the Schiaparelli module separated from the TGO and began its 3-day plummet to the planet’s surface. Twelve hours after separation, the TGO automatically corrected its course and continued into orbit around the red planet, while the module began its fiery descent into the Martian atmosphere. The TGO will continue to orbit Mars sending back atmospheric and temperature data to the ESA.
When the module hits the outer atmosphere at an elevation of 121 kilometers on October 19, it will be falling at a speed of nearly 21,000 km/h. During this phase, which lasts only a few minutes, atmospheric resistance will begin slowing down the still-dormant module. An outer aeroshell layer will protect the module from the intense heat experienced during this re-entry phase, which lasts a little more than three minutes. During its descent, Schiaparelli will communicate with the Orbiter.
Once the module reaches an altitude of 11 kilometers, its rate of descent will have been slowed to 1700 km/h by atmospheric drag and a parachute will be deployed to slow the module down even further. Forty seconds after the parachute opens, the front aeroshell that protected the module during re-entry will be jettisoned, and an altitude-measuring radar will be activated. The parachute will slow down the module to 250 km/h, allowing it to descend gently to a height of 1-2 kilometers.
At approximately 1 kilometer, the parachute and the back part of the aeroshell will be released, and the module will activate its three hydrazine thrusters to control its speed as it lands. When it is just two meters above the surface of the planet, the thrusters will shut off, and the module will freefall for the rest of its landing.
The module has an impact-resistance lander that will crush upon impact much like the crumple zone on a car. Once it lands on the surface of Mars, the Schiaparelli module will begin the data collection stage of the mission. It also will initiate communication to Earth using the ESA’s Mars Express spacecraft and NASA’s Relay Orbiter.
The historic landing will be live-streamed at on the ESA’s website starting at 3:00 p.m. CET (9 a.m. ET) on October 19. A special edition video will be available via Facebook Live on the ESA’s Facebook page.