If a particularly delicate operation had not proceeded as planned, it would have been impossible to deploy the Mars Express lander, Beagle 2, on arrival at Mars.

This crucial operation consisted of releasing Beagle-2's launch clamps. These clamps are extra attachments that ensure the lander stays perfectly fixed to the spacecraft during the launch and is not affected by launch vibrations. After the launch, these clamps are no longer needed, since another mechanism keeps Beagle 2 in place during the six-month trip to the Red Planet.

This second mechanism allows Mars Express to deploy Beagle 2 on arrival at Mars. However, if the launch clamps had not released today, the second mechanism would have failed. "The Beagle-2 mission would have been over before it had even started!" commented ESA Lander Manager, Con McCarthy.

The release of the launch clamps started at 10.10 CEST and lasted about 30 minutes. The release mechanism itself is unusual. Usually, launch clamps contain a firework-like mechanism, but Mars Express had a much gentler release mechanism for Beagle. It consisted of a sleeve over a clamp bolt; an electric current heats the sleeve to about 100 C. At that temperature, the sleeve expands and the bolt snaps. There were three bolts and they all broke in sequence.

"We had to wait two minutes for the expansion of the sleeve which snapped the bolt. The atmosphere in the room was tense and those two minutes seemed to last an eternity! When the first bolt went, a lot of tension was released," says McCarthy.

There are more hurdles ahead but Mars Express is demonstrating that it can deal with the many challenges on the way to the Red Planet.

Mars Express launch replay, http://www.esa.int/SPECIALS/Mars_Express/index.html

Related articles

* Mars Express en route for the Red Planet

http://www.esa.int/esaCP/SEMIKNS1VED_index_0.html

* Mars Express -- ESA sets ambitious goals for the first European mission to Mars http://www.esa.int/esaCP/SEMV72S1VED_index_0.html

* ESA's Mars Express ready for launch

http://www.esa.int/esaCP/SEML5JR1VED_index_0.html

* Mars Express leaves for Baikonur http://www.esa.int/esaCP/SEM2DO8YFDD_index_0.html

Related links

* ESA Science http://sci.esa.int/

* Live images of Mars Express http://sci2.esa.int/spacecam/marsexpress.htm

* Russian Space Agency http://www.rosaviakosmos.ru/english/eindex.htm

The Soyuz/Fregat lifts off on 2 June 2003 with ESA's Mars Express. Europe's first mission to the Red Planet leaves Earth when the positions of the two planets make for the shortest possible route, a condition that occurs once every twenty-six months. The intrepid spacecraft will start its six-month journey from the Baikonur launch pad in Kazakhstan onboard a Russian Soyuz/Fregat launcher.

Credits: ESA 2001. Illustration by Medialab.