Feature: Lecture - Professor Ian Morison's Life on Mars talk at the Museum of London - Feb 18th
Published: 11 February 2010
by JOSH LOEB
AN inconceivably long time ago, life emerged on Mars. It took the form of microscopic organisms which found their way to Earth on a meteorite and evolved into the array of complex plants and animals that exist on this planet today.
Fast forward millions of years and Earth has become too hot for life, while on Mars the climate is pleasant.
After its sojourn on Earth, lasting a few billion years, life departs our waters and plains and returns to the Martian mother planet where it endures for a few thousand million years before the Sun burns out.
This vision of the origin and future of life as we know it is not far-fetched, according to Professor Ian Morison of Gresham College, Holborn. Indeed, in parts it is highly probable.
Morison estimates there is “a 70 per cent chance” that life once twitched on the seemingly desolate surface of our near neighbour in the Solar System. The chance that Martian life exists today is “about 30 per cent”.
Morison also claims: “It is not impossible that life emerged first on Mars and was brought to Earth on a meteorite.”
To support his assertion that life probably existed at some point on the red planet, he cites tantalising comments by David McKay, the head of a team of American astrobiologists currently scrutinising the inside of a meteorite on loan from the Natural History Museum.
In a recent interview, McKay said his team were “very, very close to proving that there is or has been life on Mars” – and hinted that they may provide proof this year.
In addition to signs of life in meteorites (evidence includes pits of carbon-rich material, possibly produced by bacteria), Morison believes the presence of permafrost on Mars indicates there was once water there. In the Martian atmosphere, meanwhile, the presence of methane is encouraging. “Methane cannot last for long in an atmosphere,” Morison says. “Its presence implies a current source.
“It is produced by biological processes and could be the result of decayed life forms, so indicating that life did, at one time, exist.
“On the other hand, the gas could indicate the presence of volcanic activity – and if there were volcanoes on Mars, some areas beneath the planet’s surface would still be warm enough to support certain life forms.”
Morison is no X-Files-obsessed alien hunter but a respected 66-year-old scientist who, after building his first telescope aged 12 out of lenses given to him by an optician, read physics and maths at Oxford before embarking on a career in astronomy.
He has headed-up high-profile projects at Jodrell Bank in Cheshire, including a radioastronomy experiment that, he says, “scanned for messages from ET” – with no success, apparently.
Nonetheless, in recognition of his work, the Minor Planets Committee of the International Astronomical Union recently named an asteroid after him. At Gresham Collage he holds a post whose previous incumbents include none other than Sir Christopher Wren – “an astronomer before he was an architect”, Morison explains.
On Thursday (February 18), he will address an audience at the Museum of London on the subject of Martian life. Those hoping to hear about advanced civilisations are set to be disappointed – the planet, he says, is unlikely ever to have played host to anything more complex than lowly bacteria.
“The myth of advanced life on Mars was not finally dispelled until Nasa’s Mariner spacecraft reached Mars in the 1960s,” Morison says. “This was perhaps why Orson Welles’s 1938 radio programme War of the Worlds, broadcast in the form of a breaking news story rather than a play, caused such panic.”
But that is not to say that Mars could never play host to intelligent life. In time, bacteria could evolve into more sophisticated lifeforms. And Mars could even act as a “lifeboat” for our species when Earth becomes uninhabitable.
“Our sun is getting hotter,” says Morison.
“Even without climate change, in about 1,000 million years our planet will be too hot. But at the same time, increasing temperatures will result in the atmosphere on Mars becoming more suitable for life.”
What irony if, instead of war-mongering Martians invading our planet to slay us, creatures from Mars are in fact our ancestors and the planet a potential bolthole for us when Earth reaches boiling point – if, that is, there are still humans around in 1,000 million years.
• Ian Morison’s lecture Life on Mars? will take place at the Museum of London, London Wall, EC2, on Thursday February 18 at 1pm. Entrance is free.
Mars - The Red Planet - What we Know
• At this time of year, Mars can be seen with the naked eye from Earth. It appears as a ‘salmon pink star’ in the southern sky.
• The planet has about half the diameter of Earth but only one tenth its mass.
• The reddish tint is due to oxides of iron on the surface.
• With current spacecraft technology, the journey to Mars takes between seven months and one year.
• In the 19th century, observations of the planet seemed to suggest there were ‘man made’ canals there – but closer inspection by later scientists put paid to this idea.