Mars has attracted huge scientific interest over the centuries and has become the centre of conflicting thoughts and theories. Since the first pictures of Mars in 1965, trips to the red planet have revealed a familiar world, yet different enough to put our perceptions to the test and really make us ponder over what makes a planet work.
Like Earth, Mars has polar ice caps and clouds in its atmosphere, seasonal weather patterns, volcanoes and other recognisable features. Yet its conditions are a million miles from those on Earth.
Beneath its hazy pink sky, Mars is rocky, cold and sterile – definitely not one for the faint hearted! Like the other terrestrial planets – Mercury, Venus and Earth – the surface of Mars has metamorphosed through volcanoes and atmospheric effects such as dust storms.
The psychological impact of a long term stay in space cannot be underestimated. The risks to human health on long-duration missions beyond Earth’s orbit, if not dealt with and solved, represent the greatest challenge to human exploration of deep space.
Confinement on spacecraft and isolation from friends and family can cause deep psychological trauma. Many people simply would not react well to being trapped in an enclosed space with a handful of other individuals for years at a time.
Among some of the risks to health is the weakening of bones due to life without gravity and the exposure to solar and cosmic radiation. Radiation is everywhere in space. Here on Earth the effects are minimal; our atmosphere protects us from the more harmful effects. However, empty space is consumed by it.
An extended mission would inevitably involve a cumulative build-up of radiation damage and, worryingly, nobody knows what sort of a threat this radiation really poses. For example, the appearance of a solar flare while astronauts are in transit might pose a serious problem: such a flare might impregnate a ship's inhabitants with a lethal dose of radiation.
Despite the many problems that a program of extended human exploration must overcome, people still continue to push for it. People dreamed of walking on the moon long before any country thought of instituting a space program. Now that people have walked on the moon, some have adopted Mars as an even more exotic and desirable target.
An average Martian year is 687 days long
The average length of a day is 24 hours and 37 minutes
The average speed at which Mars orbits theg sun is 14.5 miles per second
The diameter of Mars is 4,222 miles
Mars weighs 641,850 trillion kilogrammes
Gravity is 0.375 that of Earth
Temperatures on Mars range from -125 to 23 °F, with an average of -81 °F, meaning it never gets above Earth's freezing point
Mars is an average of 141,633,260 miles from the sun
The atmosphere of Mars is made up almost entirely of carbon dioxide with some nitrogen, argon and a little water vapour
Mars has two moons, called Phobos and Deimos