The January 2003 launch of ESA’s Rosetta comet chaser by an Ariane 5 rocket
was confirmed on Tuesday, 19 June, at the Paris Air Show.

The signatories at the official ceremony marking the completion of the Rosetta
launch services contract negotiations were the ESA Science Director, Professor
David Southwood, and Arianespace Chairman and CEO, Jean-Marie Luton.

Ariane 5 is one of the few rockets in the world with the payload lift
capability required to send the three tonne Rosetta spacecraft towards the
distant comet.

“The 2003 launch will mark the first time an Ariane 5 has launched a
spacecraft beyond Earth orbit,” said Dr John Ellwood, the ESA project manager
for Rosetta.

Other key factors were the willingness of Arianespace to do everything possible
to ensure that the launch will take place within the three-week launch window
and the launcher’s ability to perform an extended coast phase with its EPS
upper stage.

After launch from Kourou spaceport in French Guiana, the EPS stage and its
Rosetta payload will remain in a 4000 km x 200 km coast orbit for just under
two hours. Prior to reaching perigee (the closest point to the Earth), the
upper stage will be ignited, injecting Rosetta into the required Earth escape
trajectory towards Mars.

“We’re very happy to be able to use this extended coast phase capability of
Ariane 5, which is critical to the Rosetta mission,” said Professor Southwood.

Rosetta is one of the Cornerstones in ESA’s long-term scientific programme.
Its objective is to carry out the most intensive and detailed studies ever
made of a comet, and hence hopefully unlock the mystery of how life evolved
on Earth. The small cosmic snowballs we know as comets are generally regarded
as the most primitive objects in the Solar System, the building blocks from
which the Earth and other planets were formed some 4.6 billion years ago.

During its eight-year odyssey to Comet 46P/Wirtanen, Rosetta will swing by
Mars once and Earth twice, using their gravity to provide the energy needed
for its voyage into deep space. The extended trek will also include flybys
of two unusual asteroids, Siwa and Otawara.

Rosetta will eventually rendezvous with Comet 46P/Wirtanen in November 2011.
While the Rosetta Orbiter’s payload of scientific instruments studies the
comet from close range — with the closest observations made from a distance
of about 1 km — a small lander will be released onto the comet’s surface to
make direct observations of the solid nucleus.

The Orbiter’s comet reconnaissance mission will continue for nearly two years,
during which it will monitor the dramatic changes that take place as the
nucleus begins to vapourise in the warmth of the Sun.


* Rosetta home page

* Arianespace home page


[Image 1:]
ESA’s Science Director, Professor David Southwood (right), and Arianespace
Chairman Jean-Marie Luton, after the Rosetta launch contract signing.

[Image 2:]
John Ellwood (left) shows a model of the Rosetta Orbiter to Professor
Southwood, with a model of the small lander in his right hand.

[Image 3:]
Ariane 5 at lift-off.