Over the centuries, astronomers thought the dark lines on its surface might be canals, built by an ancient civilisation for carrying water.
The Mariner missions to Mars in the 1960s and 1970s ended these romantic notions by revealing them to be impact craters similar to those found on the Moon.
The Viking landers in 1976 served to reignite the hope that life may have existed by revealing the planet to have almost certainly once had an abundance of water, which is essential for life.
A few weeks ago, the Mars Express space probe was launched from Baikonur in Kazakhstan to begin its six-month journey.
Scientists hope the Mars Express will help to answer questions raised by previous missions such as: if Mars was once covered by vast oceans, how did it evolve to the desert it is today? It will also try to finally answer the question of whether life once existed on Mars and even the possibility that life may still be present.
The space probe weighs 1120kg and has been manoeuvred into a Mars-bound trajectory by its on-board propulsion and steering system. It will travel away from the Earth with a relative speed of over 3km/s and cover 400 million kilometres in six months.
In September, it is expected to perform a mid-journey correction to its trajectory after which the probe will be largely deactivated until late November.
Meanwhile, the Mars Express will be in orbit around the planet also carrying out a detailed investigation of the planet. A very high resolution stereo camera (HRSC) is hoped to send back to Earth photographs of the Red Planet’s surface. The Mars Express will then relay all information back to Earth.
There is much discussion in this new millennium of sending a human crew to Mars. Although the Martian climate is harsh – with extremely low atmospheric pressure and sub-zero temperatures – the only obstacles to establishing a human presence on Mars are purely engineering problems.
Should a human crew ever travel to Mars it is likely the aim of the mission will be to establish a permanent presence, leaving behind them an infrastructure that can be used by their successors.