Preparations for Arianespace Flight 158 entered their final phase today
following completion of the launch readiness review at the Spaceport in
French Guiana.

The readiness review, which is held before every flight, validates the
readiness of the launcher, its payload, the Spaceport’s ground
infrastructure and the network of tracking stations that will follow the
mission.

Flight 158 carries a very special passenger: the European Space Agency’s
Rosetta comet intercept spacecraft. Rosetta will meet up with
Churyumov-Gerasimenko after a 10-year journey, imaging the comet and
releasing a lander to its surface.

Liftoff of Flight 158 will occur in the early morning hours of February 26
from the Spaceport’s ELA-3 launch complex. Instead of the typical launch
window used for Ariane 5 missions with geostationary satellite payloads,
Flight 158 has a very specific launch slot: 49 seconds past 4:36 a.m.

After a prolonged ballistic phase and delayed ignition of the Ariane 5’s EPS
upper stage, Rosetta is to be released on an Earth escape trajectory that
will lead to its encounter with comet Churyumov-Gerasimenko in 2014.

The industrial team that produced Rosetta involves more than 50 contractors
from 14 European countries and the United States. The prime spacecraft
contractor is Astrium Germany, and major subcontractors are Astrium UK (for
the spacecraft platform), Astrium France (spacecraft avionics) and Alenia
Spazio (assembly, integration and verification).