Evidence builds for life on Mars
A team of UK scientists have produced powerful new evidence that life may still exist on Mars. Their research reveals that swamp gas detected in the martian atmosphere can NOT be caused by meteorites hitting the red planet.
The UK experiments were carried out by a team at London’s Imperial College. Their results are published tomorrow in the journal Earth and Planetary Science Letters.
Methane can only last a limited time of a few hundred years in the atmosphere of Mars before it is destroyed by sunlight.
The puzzle facing scientists therefore is that it must be constantly replenished by an unknown source – which many believe must be a simple form of life.
Mars is regularly hit by meteorites from space. The Imperial College team checked whether the methane could be produced by intense heat on the space rocks as they entered the martian atmosphere.
But laboratory tests recreating this searing bombardment failed to produce high enough levels of methane. They heated meteorite fragments to 1,000° C and then used a device called a spectrometer to measure the gases given off.
This showed that meteorites can only account for 10 kg of methane a year – way below the 100-300 tons needed to top up the levels of methane that are observed in the martian atmosphere.
Co-author of the new study, Dr Richard Court, said: “Meteorites vaporizing in the atmosphere are a proposed methane source but when we recreate their fiery entry in the laboratory we get only small amounts of the gas. For Mars, meteorites fail the methane test.”
The only alternative explanation now is that the gas is produced by volcanic rock reacting with water on Mars. But the UK team says that previous studies have ruled out volcanism as a cause.
Professor Colin Pillinger, of the Open University, who was behind Britain’s ill-fated Beagle 2 mission to Mars in 2003, says he does not accept a volcanic explanation.
He points out that the plumes of methane announced by NASA in January are not being produced in areas where there are volcanoes. He told Skymania News: “Methane is a product of biology. For methane to be in Mars’ atmosphere, there has to be a replenishable source.
“The most obvious source of methane is organisms. So if you find methane in an atmosphere, you can suspect there is life.”
Now scientists are keenly awaiting a joint NASA/European probe to Mars in 2018 to dig for direct contact with any mini-Martians. The Imperial team have developed instruments to extract organic material from martian rocks.
Professor Mark Sephton, of Imperial College, said: “As Sherlock Holmes said, eliminate all other factors and the one that remains must be the truth. The list of possible sources of methane gas is getting smaller and excitingly, extraterrestrial life still remains an option. Ultimately the final test may have to be on Mars.”
Last week, a NASA team produced images of what they claim is a colony of martian bacteria in a meteorite kept at London’s Natural History Museum, boosting the idea that alien organisms were brought to Earth from Mars.
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