An international team of researchers has discovered traces of methane in Martian meteorites, a possible clue in the search for life on the Red Planet.
The researchers examined samples from six meteorites of volcanic rock that originated on Mars. The meteorites contain gases in the same proportion and with the same isotopic composition as the Martian atmosphere. All six samples also contained methane, which was measured by crushing the rocks and running the emerging gas through a mass spectrometer. The team also examined two non-Martian meteorites, which contained lesser amounts of methane.
The discovery hints at the possibility that methane could be used as a food source by rudimentary forms of life beneath the Martian surface. On Earth, microbes do this in a range of environments.
"Other researchers will be keen to replicate these findings using alternative measurement tools and techniques," said co-author Sean McMahon, a Yale University postdoctoral associate in the Department of Geology and Geophysics. "Our findings will likely be used by astrobiologists in models and experiments aimed at understanding whether life could survive below the surface of Mars today."
The discovery was part of a joint research project led by the University of Aberdeen, in collaboration with the Scottish Universities Environmental Research Centre, the University of Glasgow, Brock University in Ontario, and the University of Western Ontario.
"One of the most exciting developments in the exploration of Mars has been the suggestion of methane in the Martian atmosphere," said University of Aberdeen professor John Parnell, who directed the research. "Recent and forthcoming missions by NASA and the European Space Agency, respectively, are looking at this, however, it is so far unclear where the methane comes from, and even whether it is really there. However, our research provides a strong indication that rocks on Mars contain a large reservoir of methane."
Co-author Nigel Blamey, of Brock University, said the team plans to expand its research by analyzing additional meteorites.
Yale's McMahon noted that the team's approach may prove helpful in future Mars rover experiments. "Even if Martian methane does not directly feed microbes, it may signal the presence of a warm, wet, chemically reactive environment where life could thrive," McMahon said.
terça-feira, 16 de junho de 2015
quarta-feira, 10 de junho de 2015
Crystal Caves museum owner believes the theft of 12kg Wolf Creek specimen was more about pursuing an object of desire than its monetary value.
A rare meteorite the size of a soccer ball has been stolen from a Queenslandmuseum whose owner suspects the work of an unscrupulous collector.
The 11.25kg space rock, worth more than $16,000, was stolen from the Crystal Caves museum in Atherton, north Queensland, early on Monday.
The museum’s owner, Ghislanie Gallo, said she believed the theft – which police suspected was carried out by two men in hooded jumpers with white masks – was less about the meteorite’s value than it being an object of desire among a narrow group of enthusiasts.
The meteorite was only recently donated to the museum, which is permitted to display it but not sell it.
The rare specimen was discovered in Wolf Creek in Western Australia in 1973, the year before the area was declared a national park and all meteorites subsequently found deemed property of the crown.
Gallo said she understood it was illegal to take Australian meteorites out of the country. Media attention generated by the theft also meant “it’s going to be pretty hard to shift”.
“There’s a big part of me that’s hoping whoever did is freaking out right now and is going to dump it at my back gate. That would be the ideal outcome,” she said.
CCTV footage of the suspected thieves obtained by police has fuelled Gallo’s suspicion that “whoever broke in was doing it for somebody else”.
“Somebody who really wanted it found a couple of hoodlums and said, ‘I’ll give you a couple of grand to break into Crystal Caves and steal this thing’,” she said. “They probably had no idea what it was and what it was worth to a collector.
“People that are into this stuff – it’s from outer space and people have all these metaphysical ideas about properties of things from outer space.
“Who knows, maybe it was a nutter with enough cash to pay somebody to go and steal it from them?”
Gallo said she had been approached by a collector at her Cairns shop several months ago wanting to buy a smaller Wolf Creek meteorite she had.
“I said, I’m not selling it to you, it’s not for sale,” she said.
“Then we got this much bigger meteorite donated to us and we did get a bit of TV publicity from that. You start thinking about people like that and you go, maybe it’s a case of ‘you won’t sell me one, I’ll just help myself’. I don’t know.”
Atherton police senior sergeant Richard Trotter said he understood the value of the meteorite was not widely known in the town before the robbery.
“Would you know what a meteorite is worth? Because I certainly didn’t,” Trotter said.
“It’s an unusual thing for somebody to go to that much trouble to steal. And it would stand out certainly if somebody put it up on eBay, wouldn’t it? I can’t imagine it being that easy to move on for any sort of profit. It’s a very strange thing to see, to be honest.”
Trotter said no information from the public had yet been forthcoming. He renewed an appeal to hear from anyone “who might know the faces on the camera or have heard something or seen something or been offered a piece of the meteorite”.
Astronomy expert David Reneke, from Australasian Science magazine, told the ABC the meteorite could be broken up into smaller pieces and sold on the black market.
“These things are valuable for a lot of reasons, not only because of the mineralogy but because of what they represent,” he said.
“These bits of rock are usually between 4.5bn and 5bn years old. They come from a place between Mars and Jupiter and if you ever wanted a pristine part of a planet like Earth, this is where you go.”
Gallo said she believed there was “no way” a thief who had any appreciation of meteorites would break it up for sale.
“I don’t think it’s about the value. I think a collector wanted it,” she said.
“Why would you bust up a perfect specimen into little pieces? That would break my heart if that happened. That’s like breaking up the Mona Lisa and selling it in bits.”
Publicado por Jorge M. Gonçalves às 11:33 da tarde