[meteorite-list] ExoMars 2016 Targest March Launch Window

[Ron Baalke]

http://www.esa.int/Our_Activities/Space_Science/ExoMars_2016_targets_March_launch_window

ExoMars 2016 Targest March Launch Window
European Space Agency
18 September 2015

A problem recently discovered in two sensors in the propulsion system 
of the entry, descent and landing demonstrator module has prompted the 
recommendation to move the launch of the ExoMars 2016 mission, initially 
foreseen in January, to March, still within the launch window of early 
2016.

ExoMars is a joint endeavour between ESA and Russia's Roscosmos space 
agency. The recommendation was made in full coordination between the two 
agencies and will be finally endorsed by a joint steering board on 24 
September.

The Schiaparelli module will prove key technologies to demonstrate Europe's 
capability to make a controlled landing on Mars.

The 600 kg Schiaparelli will ride to Mars on the Trace Gas Orbiter, which 
will subsequently enter orbit around the Red Planet to begin its five-year 
mission of studying atmospheric gases potentially linked to present-day 
biological or geological activity.

Schiaparelli will separate from the orbiter three days before they reach 
Mars, entering the atmosphere at 21 000 km/h. Following aerobraking in 
the upper atmosphere and a parachute phase, a liquid-propellant thruster 
system will brake the module to less than 5 km/h at a height of about 
2 m above the surface.

At that moment, the thrusters will be switched off and the lander will 
drop to the ground, where the impact will be cushioned by a crushable 
structure built into the module.

Less than eight minutes will elapse between the moment when Schiaparelli 
enters the atmosphere to its landing on Mars in a region known as Meridiani 
Planum.

However, a defect was recently found in two pressure transducers mounted 
in the propulsion system.

"A failure in the production process of the pressure transducers has been 
identified and this leads to concerns about leakage, which represents 
a major risk to a successful landing on Mars," says Don McCoy, ESA ExoMars 
Project Manager.

"ESA has decided not to accept this risk and to remove both units from 
the landing module, the knock-on effect being that we can no longer maintain 
the January 2016 launch window and will instead move to the back-up launch 
window in March.

"We are pleased to have identified the issue in good time, and are focusing 
all our efforts to launch on 14 March."

The sensors are not part of the control loop necessary for landing, but 
would rather have gathered ancillary data for monitoring the system. In 
order to meet the new launch window, the decision was made to remove the 
parts, rather than replace them.

The later window is open 14-25 March and, thanks to the relative orbital 
positions of Earth and Mars, the mission will still arrive at Mars in 
October, just as if launched in January.

A set of scientific sensors on Schiaparelli will collect data on the atmosphere 
during the entry and descent, and its instruments will perform local environment 
measurements at the landing site.

However, because Schiaparelli is primarily aimed at demonstrating technologies 
needed for landing in preparation for future missions, the scientific 
phase is limited: the module is planned to operate on the surface for 
only a short time, powered by batteries.

Schiaparelli will remain a target for future laser ranging studies, as 
it carries a reflector designed for this purpose.

The Trace Gas Orbiter, along with other ESA and NASA missions already 
orbiting Mars, will provide communications support from Schiaparelli during 
descent and on the surface, relaying the data back to Earth.

Subsequently, the orbiter will begin its programme of extensive scientific 
observations, while also acting as a data relay for future missions. These 
include ExoMars 2018, which will see a rover and an instrumented platform 
on the surface.

Both ExoMars missions will be launched on Russian Proton rockets from 
Baikonur in Kazakhstan.


For further information, please contact:

Markus Bauer
ESA Science and Robotic Exploration Communication Office
Tel: +31 71 565 6799
Mob: +31 61 594 3 954
Email: Markus.Bauer at esa.int

Rolf de Groot
ESA Coordinator for Robotic Exploration
Email: Rolf.de.Groot at esa.int