ExoMars Trace Gas Orbiter and Schiaparelli Mission (2016)
The first mission of the ExoMars programme, scheduled to arrive at Mars in October 2016, consists of a Trace Gas Orbiter plus an entry, descent and landing demonstrator module, known as Schiaparelli. The main objectives of this mission are to search for evidence of methane and other trace atmospheric gases that could be signatures of active biological or geological processes and to test key technologies in preparation for ESA's contribution to subsequent missions to Mars.
The Orbiter and Schiaparelli were launched together on 14 March 2016 on a Proton rocket and will fly to Mars in a composite configuration. By taking advantage of the positioning of Earth and Mars the cruise phase can be limited to about 7 months, with the pair arriving at Mars in October.
Three days before reaching the atmosphere of Mars, Schiaparelli will be ejected from the Orbiter towards the Red Planet. Schiaparelli will then coast towards its destination, enter the Martian atmosphere at 21 000 km/h, decelerate using aerobraking and a parachute, and then brake with the aid of a thruster system before landing on the surface of the planet.
From its coasting to Mars until its landing, Schiaparelli will communicate with the Orbiter. Once on the surface, the communications of Schiaparelli will be supported from Mars Express and from a NASA Relay Orbiter. The ExoMars Orbiter will be inserted into an elliptical orbit around Mars and then sweep through the atmosphere to finally settle into a circular,
Trace Gas Orbiter - Searching for signature gases in the Martian atmosphere
The Orbiter spacecraft is designed by ESA, while Roscosmos provides the launch vehicle, a Proton rocket. A scientific payload with instruments from Russia and Europe is accommodated on the Orbiter to achieve its scientific objectives. The Orbiter will perform detailed, remote observations of the Martian atmosphere, searching for evidence of gases of possible biological importance, such as methane and its degradation products. The instruments on the Orbiter will carry out a variety of measurements to investigate the location and nature of sources that produce these gases. The scientific mission is expected to begin in December 2017 and will run for five years. The Trace Gas Orbiter will also be used to relay data for the 2020 rover mission of the ExoMars programme until the end of 2022.
Schiaparelli prepares for thermal tests.
Credit: ESA – B. Bethge
|Schiaparelli - without heat shield and back cover. Credit: ESA/ATG medialab|
Schiaparelli is expected to survive on the surface of Mars for a short time by using the excess energy capacity of its batteries. The science possibilities of Schiaparelli are limited by the absence of long term power and the fixed amount of space and resources that can be accommodated within the module; however, a set of scientific sensors are included to perform limited, but useful, surface science.
ExoMars 2016 Mission Phases Overview
|Launch||14 March 2016|
|Schiaparelli – Trace Gas Orbiter separation||16 October 2016|
|Trace Gas Orbiter insertion into Mars orbit||19 October 2016|
|Schiaparelli enters Martian atmosphere and lands on the target site||19 October 2016|
|Schiaparelli science operations begin||
|Trace Gas Orbiter changes inclination to science orbit (74°)||December 2016|
|Apocentre reduction manoeuvres (from the initial 4-sol orbit to a 1-sol orbit)||December 2016|
|Aerobraking phase (Trace Gas Orbiter lowers its altitude to 400 km circular orbit)||January 2017 - November 2017|
|Trace Gas Orbiter science operations begin. (In parallel, TGO will start data relay operations to support NASA landers on Mars.)||December 2017|
|Superior solar conjunction (critical operations are paused while the Sun is between Earth and Mars)||11 July - 11 August 2017|
|Start of the Trace Gas Orbiter data relay operations to support communications for the rover mission and for the surface science platform||April 2021|
|End of Trace Gas Orbiter mission||December 2022|
Keeping in touch far from home
After launch and throughout the cruise phase, the spacecraft unit made up of the Trace Gas Orbiter and Schiaparelli is operated by ESA through the space communications network of ESA's European Space Operations Centre (ESOC).
After separation, the Orbiter will monitor the UHF transmission from Schiaparelli from its coasting to Mars until its landing. ESA's Mars Express and a NASA Relay Orbiter will act as a data relay for Schiaparelli during its surface operations. Furthermore, ground-based communication arrays will also track the UHF signal during the entry, descent and landing phases.
ESA will be in full control of the Orbiter during all phases of its mission, including insertion into Mars orbit, orbit control, aerobraking, science operations and Mars communications operations.