PASADENA, Calif. - Experts from Centre National d'Etudes Spatiales (CNES), the French space agency along with a team from the European Space Agency (ESA) were invited by NASA to the Jet Propulsion Laboratory to observe the Mars Polar Lander's touchdown last week. As Europe prepares for its upcoming Mars missions -- scheduled for 2003 and 2005 -- the French and their European counterparts were keeping a close eye on the proceedings.

On the heels of Mars Express, the Mars Sample Return mission is a very ambitious joint mission between NASA and CNES engineers. The mission will have two stages. In 2003 an American Delta 3 rocket will launch a two-ton spacecraft to Mars consisting of a lander, a Mars Ascent Vehicle (MAV) and a 100-pound rover called Athena. The Mars soil samples collected by the Rover, over several months, will be stored inside a grapefruit-sized metal sphere, which will be launched by the three-stage MAV. It will be placed in a 400-mile (644-kilometer) parking orbit above Mars where it will await the arrival of the yet-to-be-launched orbiter.

In August 2005, a European Ariane 5 rocket will launch another multi-target mission from French Guiana. It will carry a second U.S.-built lander with the same Athena and MAV components as the earlier one, along with a French-made orbiter. This 2.7-ton spacecraft will be equipped with a sample return capsule and four small French-designed probes called Netlanders.

The Mars Sample Return Orbiter, under CNES management, will perform a space first by getting into Mars' orbit using a revolutionary "aerocapture" technique. This risky atmosphere breaking approach requires the spacecraft to go as low as 25 miles into the martian atmosphere to achieve deceleration by intense friction. This new fuel-free orbit insertion around the Red Planet will save more than one ton of propellant.

While the U.S. lander performs the same mission as the earlier one in 2003, the French orbiter will release its four Netlanders, each weighing 500 pounds. After a parachute-slowed descent, they will inflate airbags to absorb the shock of impact. Organized as a small constellation, the Netlanders microprobes will be used to carry out geological, seismic and other geophysics experiments on the Red Planet.

In the meantime, in 2006 the French-built Mars Sample Return Orbiter will recover the second sphere.

In 2007 the orbiter will begin its return trip back to Earth. When it reaches Earth's immediate vicinity, it will release the little 70-pound (32-kilogram) sealed capsule containing the first Mars samples which will reenter the atmosphere and land in Utah in May 2008.

"This is a highly risky mission, a lot new things can fail, but this is the challenge of space exploration. It's a unique opportunity for CNES. It will be taking part in the first Mars Sample Return mission in 2005, which marks the culmination of NASA's ongoing Mars exploration program," says Jacques-Emile Blamont, key adviser to the CNES director-general. This ambitious program of cooperation between NASA and CNES -- whose participation is expected to be around 40% -- will be finalized early next year.

For the Europeans, their own mission poses different challenges. Mars Express got this name because of two differences -- faster and cheaper. The 265-pound (120-kilogram) spacecraft -- from concept to launch -- will be ready in a record time of five years, and at a cost of roughly $180 million, including the launcher and the scientific payload. The probe itself will be the cheapest planetary vehicle ever built with a price tag of dollars $60 million.

Its launch is slated for June 2003 on a Russian Soyuz rocket, refitted for commercial use by the French company, Starsem. Thanks to an exceptionally favorable launch window, the ESA interplanetary probe will be in a near-polar elliptical orbit around Mars in December 2003.

Seven on-board scientific instruments will perform a variety of tasks such as: high-resolution photo-geology; mineralogical mapping; using radar to probe through the surface of the planet in a search of underground ice; monitoring of the global circulation of Mars' atmosphere and studying the interaction between the atmosphere and the planet's surface.

Attached to this orbiter, is the Beagle 2, a 132-pound (60-kilogram) lander that will conduct geo-biological and geo-chemical experiments on the surface to search for possible signs of past or present life. This U.K.-funded probe will look for signs of fossilized life in an attempt to understand if life appeared on Mars at the same time as on Earth and, if so, why it disappeared.