|Entry, Descent, and Landing
What is Entry, Descent, and Landing?
The entry, descent, and landing (EDL) phase begins when the spacecraft
reaches the Mars atmospheric entry interface point (3522.2 kilometers or
about 2,113 miles from the center of Mars) and ends with the lander on
the surface of Mars in a safe state.
What will happen during Entry, Descent, and Landing?
Five days before reaching Mars in December 2003, a spring
mechanism on board Mars Express will eject the Beagle 2 lander. The
heat resistant shield will protect it as friction with the upper atmosphere
slows it down. When its speed has fallen to about 1600 kilometers per
hour (994 miles per hour), parachutes will deploy to slow it further.
Finally, large gas-filled airbags will inflate to protect it as it bounces to a
halt on Isidis Planitia, the selected landing site. Isidis Planitia is a large
flat basin where water may once have existed and where traces of any
past or present life might be preserved.
As soon as the lander has come to a halt, the gas-filled bags will be
released and the outer casing will open. First, solar panels will unfold
and catch sunlight that will charge the batteries, which will power the
lander and its experiments throughout the mission. Next, a robotic arm
will extend. Attached to the end of the arm is Beagle's
PAW (Position Adjustable Workbench) where most of the experiments are
located. The PAW's first job will be to move around so that the cameras
attached to it can provide a view of the landing site.
Beagle 2 must accomplish its mission in just 180 sols, or 185 Earth
days. The first few days will be spent imaging the site and running
the environmental sensors, and then the lander will start doing very
detailed rock and soil analysis.