Three spacecraft will soon be launched to Mars to continue exploration ofthe "red"planet

Tim Furniss/London

The "life on Mars" hysteria which swept the world's media in August has added a touch of spice to the launch of three new missions to the Red Planet in November and December (Flight International, 21-27 August).

The Russian Mars '96 and the US Mars Global Surveyor and Mars Pathfinder missions were all planned before NASA's speculative (and so far unproven) Mars life announcement.

If NASA thought that the sensational story would give impetus for new missions, it may be mistaken. Mars flights had already been planned for each available launch window in 1998, 2000, 2002 and 2004. If there really has ever been any life on Mars then it will not be proven until rock samples - actually known to be from Mars - are brought back to Earth and analysed. Under existing plans that will not be until 2006, on the return of the mission launched in 2004.

Speedy samples

It is possible that the Mars sample-return plans will be accelerated as a result of the publicity. Near-term programme changes could mean additional modifications to the Mars Surveyor 1998 missions of an orbiter and lander (Flight International, 20 December, 1995-2 January, 1996). The lander, which will touch down in the carbon dioxide and water ice of a polar region, will carry a new, piggyback payload, which has been added since the announcement of "life on Mars".

This will consist of two microprobes, to fly as the second New Millennium mission, Deep Space 2. They will penetrate the Martian soil to a depth of possibly 2m and will be used for proving the technology required for future penetrators which will in turn be used to search for subsurface ice and minerals to give clues about possible life on Mars.

For now, however, NASA needs to prove that it can fly a successful Mars mission before the US Congress will be persuaded to grant increased or continued funding. The space agency's last craft, the $1 billion Mars Observer, was lost just as preparations began for it to enter orbit around the planet in August 1993.

That failure triggered a call for smaller, less-expensive missions which have now been introduced under the new, "faster, smaller, better, cheaper" banner.

The Mars Global Surveyor and Mars Pathfinder missions give the example. Illustrating this new "small" approach, the Pathfinder's Mars roving vehicle is the size of a domestic microwave oven.

NASA plans to launch in 1998 the Mars Survyeor programme for a systematic exploration of the planet using orbiters and landers, culminating possibly with the sample return mission in 2004. This, by the agency's own admission, will require technologies not yet proven. NASA's New Millennium space-technology demonstrator programme will contribute to this much-needed expertise.

Cut-price doubts

NASA may be shooting itself in the foot with its "small is beautiful" approach, says the National Research Council, which questions how a Mars sample-return mission can be achieved, based on the constraints of cut-price, limited-capability missions.

The Russian space community also has problems. Starved of cash and staff since the breakdown of the Soviet Union, it has been fighting to save the Mars '96 mission, which should have flown in 1994. That has now replaced the original Mars '96 mission, which has now become Mars '98.

The Mars '96 orbiter will dispatch two small landing craft on to the surface and propel two instrumented harpoon-like penetrators to pierce the Martian soil. The orbiter will conduct a survey of the planet, on a mission similar to that of the Mars Global Surveyor.

The proposed Russian Mars '98 international mission, which will deploy a French atmospheric balloon and the first Russian roving vehicle, is in doubt, however. Russia proposes to fly experiments on board NASA's Mars Surveyor spacecraft. Further co-operation may follow as part of an unofficial Mars Together programme.

Like NASA, Russia is under pressure to perform, for its Mars spacecraft track record is poor. Its most recent probes, the Phobos 1 and 2 both failed in the vicinity of the Red Planet.

Source: Flight International