Mars

Sarah Dillon begins a series revelling in the Mars of imagination, science and history.

We are the Martians, perhaps the only consciousness the Red Planet has ever had. The ancients wove their own mythological stories about Mars, its dim redness and uncertain path visible to the naked eye. In the 19th century new, powerful telescopes scrutinized the Red Planet and astronomers considered the possibilities of life on Mars. There was, in fact, a kind of mapping war to name and identify features on the planet.

When the Italian astronomer Giovanni Schiaparelli produced a series of maps in the 1870s featuring dark channels or "canali", a powerful story began to develop: Mars was a dying planet, older, perhaps inhabited . Then, from the 1890s, American amateur astronomer Percival Lowell, using his state of the art telescope in his brand new observatory high up in Flagstaff, Arizona, convinced millions that this "dying" planet was home to a doomed civilization struggling to maintain life through an elaborate system of canals. Lowell was a supreme popularizer of science, commanding huge audiences despite the severe doubts of many in the scientific community.

Worldwide, Lowell's myth sparked volumes of popular fiction and when failed salesman Edgar Rice Burroughs penned the first of his Barsoom adventures in 1911, Martian fantasy truly took off. Its literary spell remains unbroken. Even after the Mariner probes and Viking Lander finally revealed Mars was red but dead, the Old Mars of our dreams would return.

Sarah Dillon travels to Flagstaff and the analogue Martian landscape of ochre Arizonan desert and talks to a host of Red Planet writers.

Producer: Mark Burman.

As part of Radio 4's Mars season, planetary scientist Monica Grady explores the search for life on the Red Planet.

As a small rocky planet, Mars is similar in many respects to the Earth and for that reason, many have thought it may harbour some kind of life. A hundred years ago, there was serious talk about the possibility of advanced civilisations there. Even in early 1970s, scientists mused that plant-like aliens might grow in the Martian soil. The best hope now is for something microbial. But the discovery that even simple life survives there or did some time in its history would be a profound one. We would know that life is not something special to Earth.

NASA’s Curiosity rover has discovered that 3.7 billion years ago, there were conditions hospitable to life on Mars – a sustained period of time with lakes and rivers of water. The earlier rover Spirit found deposits of silica from ancient hot springs which some planetary scientists argue bear the hallmarks of being shaped by microbes - possibly.

The next five years may dramatically advance the hunt for life on Mars. In 2020 the European and Russian space agencies will send their ExoMars rover. That will drill two metres into the Red Planet’s surface and sample material shielded from the sterilising radiation. It will analyse for life both extant and extinct. In the future, robotic or possibly human missions may even explore Martian cave systems in Mars' vast volcanoes. Monica talks to Nasa's Penny Boston whose adventures in some of the world's most dangerous caves have convinced her that underground is the best place to look.

Monica Grady is Professor of Planetary and Space Science at the Open University.

Producer: Andrew Luck-Baker