Richard Lawrence - The Mammoth Book of Space Exploration and Disaster

Reports by NASA advisory and review committees raising warnings about the shuttle fleet’s age and continued safety were cited by many members. O’Keefe stated that the concerns raised were all in reference to future safety, but there had been no indications that the current safety of the shuttle program was compromised. Another issue raised repeatedly was the budget cuts made over the past decade to planned shuttle upgrades. O’Keefe explained that, in his understanding of the shuttle’s budget history, quality assurance procedures and other program management approaches had yielded efficiencies and cost reductions, while at the same time, indicators showed safety improvements and a decrease in safety incidents both before and on orbit.

Addressing questions about the justification of manned space exploration versus robotic, O’Keefe said it was “not an issue of either/or” NASA’s approach, as it was doing with the Mars mission – to use robotic capabilities to understand the risks of human involvement and learn what would be necessary to support an eventual human mission “if it is deemed appropriate.” He mentioned the Hubble Space Telescope as an example of how unmanned exploration capabilities and human involvement worked in a complementary way to achieve outstanding science.

“This is not the beginning of the end; it is the end of the beginning,” Boehlert said in conclusion. He praised the openness and cooperation of O’Keefe and Admiral Gehman, and “the total commitment I find on the part of every person involved… to get the facts and let us be guided by the facts.”

When in 2003 the orbits of Mars and Earth brought them the closest together they had been for 60,000 years, both NASA and the European Space Agency (ESA) sent robotic missions to Mars. The ESA mission was named Mars Express; the NASA mission was named Mars Exploration Rover (MER). NASA already had a satellite, Mars Odyssey, in orbit around Mars. The missions were intended to find evidence of life on Mars, either in the past or the present .

Mars Express was an international collaboration, originally consisting of two orbiters and a lander. The orbiters were ESA’s Mars Express itself and the Japanese spacecraft Nozomi; Beagle 2 was the lander .

Mars Express was launched by a Russian four-stage Soyuz/Fregat launcher, with the Fregat upper stage separating from the spacecraft after placing it on a Mars-bound trajectory. Mars Express was mounted on the Fregat upper stage .

The spacecraft used its on-board means of propulsion solely for orbit corrections and to slow the spacecraft down for Mars orbit insertion. Electrical power was provided by the spacecraft’s solar panels which were deployed shortly after launch. When Mars was at its maximum distance from the sun (aphelion), the solar panels would still be capable of delivering 650 watts which was more than enough to meet the mission’s maximum requirement of 500 watts, equivalent to just five ordinary 100 watt light bulbs!

When the spacecraft’s view of the sun was obscured by Mars during a solar eclipse, a lithium-ion battery (67.5 amp hours), previously charged up by the solar panels, took over the power supply .

Five of the instruments on Mars Express (HRSC, OMEGA, PFS, ASPERA and SPICAM) were descendants of instruments originally built for the Russian Mars ’96 mission. Each of the seven orbiter instrument teams on Mars Express had Russian coinvestigators who contributed their intellectual expertise to the project .

The Japanese spacecraft Nozomi was intended to go into near equatorial orbit around Mars shortly after Mars Express entered polar orbit. Nozomi had been due to reach the Red Planet in October 1999, but was delayed by a problem with the propulsion system, so the two missions took the opportunity to collaborate .

They shared a common interest in the Martian atmosphere – Nozomi even carried a close relative of ASPERA, the instrument on Mars Express to study interactions between the upper atmosphere and the solar wind .

Measurements recorded simultaneously by both spacecraft from their different vantage points would provide an unprecedented opportunity to study such interactions, so the two missions agreed to a programme of joint investigations and to the exchange of coinvestigators between the instrument teams .

ESA’s Beagle 2 landed on Mars at about thesametime as NASA’s Mars Rover mission. The two space agencies made arrangements to use each other’s orbiters as back-up for relaying data and other communications from the landers to Earth .

Mars Express also intended to use NASA’s Deep Space Network for communications with Earth during parts of the mission. US scientists played a major role in one of Mars Express’s payload instruments, MARSIS, and participated as co-investigators in most other instruments .

Mars Express and Beagle 2 marked the beginning of a major European involvement in an international programme to explore Mars over the next two decades. Europe, the US and Japan are planning to send missions, but many more countries will be contributing experiments, hardware and expertise .

The Beagle 2 lander was built by a British team. Being small and light it did not have a propulsion system of its own, and had to be “carried” precisely to its destination. On 19 December 2003 Mars Express was on a collision course with Mars, at which point Beagle 2 separated from it. Mars Express then veered away to avoid crashing onto the planet by firing its thrusters to get away from the collision course and enter into orbit around Mars. This was the first time that an orbiter delivered a lander without its own propulsion onto a planet, and attempted orbit insertion immediately afterwards .

Unfortunately no signal from Beagle 2 was ever received although Mars Express sent back significant pictures and information from orbit. It is thought that the atmospheric conditions at the time Beagle 2 attempted to land resulted in it being destroyed upon impact .

On 24 January 2004 Dr John Murray of the Mars Express team stated:

Scientists are on the threshold of the most exciting discovery about humanity’s place in the Universe since Galileo and Copernicus proved that the Earth goes round the Sun.

The European Mars Express spacecraft has determined beyond reasonable doubt that water, the prerequisite for all forms of terrestrial life, still exists on the Red Planet, and that it once flowed in torrents across its surface.

These remarkable revelations about our celestial neighbour provide the most tantalising evidence yet that the miracle of life on earth may not be unique, even within the confines of the solar system.

Wherever water is found on the Blue Planet – from the tundra of Antarctica to the depths of the ocean floor – we know there is life. For life as we know it, we need water. Now we can be certain that this vital commodity is present, and may once have been abundant, on the surface of Mars.

It seems more probable than ever that the planet so long considered barren and inert, may once have supported life.

It would be no exageration to compare such a discovery to the Copernican revolution, which put paid to the notion that the Earth stood at the centre of the Universe, or the voyages of Columbus and Magellan, proving the world to be round. It would mean that life has arisen twice on planets separated by as little as 35 million miles. And if that is so, it is probably common throughout the Universe.

We are not quite there yet. Neither Mars Express, nor NASA’s Spirit and Opportunity rovers, are designed to test the soil and rock for the chemical evidence that would provide definitive proof. Indeed, the European Probe’s results make it more frustrating than ever that Beagle 2, the British lander that was sent to Mars specifically to search for life, remains incommunicado.