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NASA Mars Rover Finds Organic Matter in Ancient Lake Bed (theguardian.com)
NASA's veteran Curiosity rover has found complex organic matter buried and preserved in ancient sediments that formed a vast lake bed on Mars more than 3bn years ago. From a report: The discovery is the most compelling evidence yet that long before the planet became the parched world it is today, Martian lakes were a rich soup of carbon-based compounds that are necessary for life, at least as we know it. Researchers cannot tell how the organic material formed and so leave open the crucial question: are the compounds remnants of past organisms; the product of chemical reactions with rocks; or were they brought to Mars in comets or other falling debris that slammed into the surface? All look the same in the tests performed. But whatever the ultimate source of the material, if microbial life did find a foothold on Mars, the presence of organics meant it would not have gone hungry. "We know that on Earth microorganisms eat all sorts of organics. It's a valuable food source for them," said Jennifer Eigenbrode, a biogeochemist at NASA's Goddard Space Flight Center in Maryland. The Curiosity rover also discovered that methane on the red planet changes with the seasons. The Verge: Where the methane is coming from is still a mystery, but scientists have some ideas, including that microbes may be the source of the gas. Researchers at NASA and other US universities analyzed five years' worth of methane measurements Curiosity took at Gale Crater, where the rover landed in 2012. Curiosity detected background levels of methane of about 0.4 parts per billion, which is a tiny amount. (In comparison, Earth's atmosphere has about 1,800 parts per billion of methane.) Those levels of methane, however, were found to range from 0.2 to about 0.7 parts per billion, with concentrations peaking near the end of the summer in the northern hemisphere, according to a study published today in Science. This seasonal cycle repeated through time and could come from an underground reservoir of methane, the study says. Whether that reservoir is a sign that there is or was life on Mars, however, is impossible to say for now.
Are there the remains of a red Tesla roadster scattered around the area?
I was told by many people that organic molecules made from oil in a factory are different from the same molecules made by plants. No amount of explanation could convince them that that is not true.
That's because it is true. Because of chirality
TL:DR version: there are "left hand" and "right hand" versions of virtually every organic molecule. "Hand" refers to the orientation of the various groups of atoms in the molecule. When you make the molecule artificially, you get a 50/50 mix of left-hand and right-hand molecules. Lifeforms on Earth make 100% left-handed versions of molecules, with a few exceptions. In those exceptions, they make 100% right-handed.
So those molecules made in a factory are actually different than the same molecules made by plants.
In your defense, chirality doesn't affect the molecule's chemistry. And we have yet to scientifically demonstrate chirality affects how the molecule is processed by a living system (such as eaten and digested). There are claims that right-hand molecules can't be digested properly by humans and that makes things like HFCS bad (50% of the fructose is right-handed). But those aren't proven.