In the search for life on Mars, landers, rovers and spacecraft have been sent to the red planet to ascertain if it was once, or still is, habitable. But evidence for such life might now have been found in a meteorite that landed on Earth three years ago. Examining a meteorite named Tissint, scientists have found small fissures that were filled with carbon containing matter - and it may be of extraterrestrial biological origin. Scroll down for video explanation . The Tissint meteorite (fragment shown) fell to Earth in Morocco on 18 July 2011. It was ejected from Mars by an asteroid impact 700,000 years ago. Pieces of the meteorite were found to have fissures caused by water, and these may contain carbon of biological origin, according to a new study . The Tissint meteorite fell to Earth in the Moroccan desert on 18 July 2011. It was ejected from Mars after an asteroid crashed into the surface 700,000 years ago, sending debris into space - some of which made its way to Earth. And this meteorite, the fall of which was seen by several eyewitnesses, seems to bear signs the red planet was once habitable. Dr Philippe Gillet, director of EPFL's Earth and Planetary Sciences Laboratory, and colleagues from China, Japan and Germany performed a detailed analysis of organic carbon found in the meteorite. The Tissint meteorite fell in Tata Province, in the Guelmim-Es Semara region of Morocoo, on 18 July 2011. It broke apart in the atmosphere and rained material on to Earth, with several pieces being recovered and some being sold. It is also only the fifth Martian meteorite to be seen falling to Earth by eyewitnesses - the last being in 1962. Tissint had been ejected from the surface of Mars 700,000 years ago when an asteroid struct the surface. Of most interest is the sign of certain elements being carried into cracks in the rocks by water fluid, which has never been seen in a Martian meteorite before. They concluded that it very likely had a biological origin. The scientists argue that the carbon could have been deposited in fissures of the rock when it was still on Mars by fluid that was rich in organic matter. 'So far, there is no other theory that we find more compelling,' said Dr Gillet. Other studies of the meteorite have agreed that carbon in the meteorite is organic. However, there has been a debate as to where this carbon came from. A study in 2012 proposed that the carbon came from the crystallisation of magma at high temperature on Mars - ruling out a biological origin. But the latest study says liquids seeping into the rock at low temperatures near the surface is a more likely explanation. The Tissint meteorite fell in Tata Province (shown), in the Guelmim-Es Semara region of Morocoo, on 18 July 2011. It broke apart in the atmosphere and rained material on to Earth, with several pieces being recovered and some being sold. And it is only the fifth Martian meteorite to be spotted falling to Earth . Dr Philippe Gillet, director of EPFL's Earth and Planetary Sciences Laboratory, and colleagues from China, Japan and Germany performed a detailed analysis of organic carbon found in the meteorite. They found it very likely had a biological origin from Mars (shown) This is supported by some properties of the meteorite's carbon. Most notably, the ratio of the carbon 13 isotope to carbon 12 was similar to coal on Earth. This is important because coal has a biological origin - namely dead plant and animal matter. In the study the researchers also ruled out the chance the carbon had come from Earth - and they are now increasingly sure this meteorite proves life on Mars once existed. 'Insisting on certainty is unwise, particularly on such a sensitive topic,' warns Dr Gillet. 'I'm completely open to the possibility that other studies might contradict our findings. 'However, our conclusions are such that they will rekindle the debate as to the possible existence of biological activity on Mars - at least in the past.'
The Tissint meteorite fell to Earth in Morocco on 18 July 2011 .
It was ejected from Mars by an asteroid impact 700,000 years ago .
Pieces of the meteorite were found to have fissures caused by water .
Within these fissures elements were found that had seeped inside .
And carbon isotopes in the meteorite match that of coal on Earth .
This has a biological origin - which means Tissint might be evidence of past extraterrestrial life on Mars .
In the search for life on Mars, landers, rovers and spacecraft have been sent to the red planet to ascertain if it was once, or still is, habitable. But evidence for such life might now have been found in a meteorite that landed on Earth three years ago. Examining a meteorite named Tissint, scientists have found small fissures that were filled with carbon containing matter - and it may be of extraterrestrial biological origin. Scroll down for video explanation . The Tissint meteorite (fragment shown) fell to Earth in Morocco on 18 July 2011. It was ejected from Mars by an asteroid impact 700,000 years ago. Pieces of the meteorite were found to have fissures caused by water, and these may contain carbon of biological origin, according to a new study . The Tissint meteorite fell to Earth in the Moroccan desert on 18 July 2011. It was ejected from Mars after an asteroid crashed into the surface 700,000 years ago, sending debris into space - some of which made its way to Earth. And this meteorite, the fall of which was seen by several eyewitnesses, seems to bear signs the red planet was once habitable. Dr Philippe Gillet, director of EPFL's Earth and Planetary Sciences Laboratory, and colleagues from China, Japan and Germany performed a detailed analysis of organic carbon found in the meteorite. The Tissint meteorite fell in Tata Province, in the Guelmim-Es Semara region of Morocoo, on 18 July 2011. It broke apart in the atmosphere and rained material on to Earth, with several pieces being recovered and some being sold. It is also only the fifth Martian meteorite to be seen falling to Earth by eyewitnesses - the last being in 1962. Tissint had been ejected from the surface of Mars 700,000 years ago when an asteroid struct the surface. Of most interest is the sign of certain elements being carried into cracks in the rocks by water fluid, which has never been seen in a Martian meteorite before. They concluded that it very likely had a biological origin. The scientists argue that the carbon could have been deposited in fissures of the rock when it was still on Mars by fluid that was rich in organic matter. 'So far, there is no other theory that we find more compelling,' said Dr Gillet. Other studies of the meteorite have agreed that carbon in the meteorite is organic. However, there has been a debate as to where this carbon came from. A study in 2012 proposed that the carbon came from the crystallisation of magma at high temperature on Mars - ruling out a biological origin. But the latest study says liquids seeping into the rock at low temperatures near the surface is a more likely explanation. The Tissint meteorite fell in Tata Province (shown), in the Guelmim-Es Semara region of Morocoo, on 18 July 2011. It broke apart in the atmosphere and rained material on to Earth, with several pieces being recovered and some being sold. And it is only the fifth Martian meteorite to be spotted falling to Earth . Dr Philippe Gillet, director of EPFL's Earth and Planetary Sciences Laboratory, and colleagues from China, Japan and Germany performed a detailed analysis of organic carbon found in the meteorite. They found it very likely had a biological origin from Mars (shown) This is supported by some properties of the meteorite's carbon. Most notably, the ratio of the carbon 13 isotope to carbon 12 was similar to coal on Earth. This is important because coal has a biological origin - namely dead plant and animal matter. In the study the researchers also ruled out the chance the carbon had come from Earth - and they are now increasingly sure this meteorite proves life on Mars once existed. 'Insisting on certainty is unwise, particularly on such a sensitive topic,' warns Dr Gillet. 'I'm completely open to the possibility that other studies might contradict our findings. 'However, our conclusions are such that they will rekindle the debate as to the possible existence of biological activity on Mars - at least in the past.'
shown) fell to Earth in Morocco on 18 July 2011. It was ejected from Mars by an asteroid impact 700,000 years ago. Pieces of the meteorite were found to have fissures caused by water, and these meteorite. The Tissint meteorite fell in Tata similar to coal on Earth. This is important because coal has a biological origin - namely