Sep 27, 2020 10:20 PM
(This post was last modified: Sep 28, 2020 08:23 PM by C C.)
Underground lakes discovered on Mars that 'could be teeming with life'
https://www.mirror.co.uk/science/undergr...d-22754288
INTRO: Mars may be teeming with life in lakes underneath its south pole, according to new research. A complex system of multiple undergound lakes has been discovered at the south pole. The "patchwork" has been likened to those on Antarctica - where strange shrimp-like anthropods, tentacled jellyfish and swimming sea cucumbers hang out.
The finding suggests water is a permanent feature below the surface of the Red Planet. Co-lead author Professor Elena Pettinelli said: "The presence of sub-glacial lakes could have important consequences for astrobiology - and the presence of habitable niches on Mars."
They are rich in salt - which lowers water's freezing point. This would keep it liquid at temperatures as low as -74 C. The international team detected three reservoirs of various sizes a mile down under a thick layer of ice - and confirmed the existence of a much larger fourth. They may have been there for more than four billion years - and be home to extremophiles that can survive the harshest conditions.
It's also possible aerobes or anaerobes are there - organisms that thrive with and without oxygen, respectively. The study published in Nature Astronomy is based on an analysis of data from the Mars Express orbiter... (MORE)
Ancient microbial life used arsenic to thrive in a world without oxygen
https://theconversation.com/ancient-micr...gen-146533
INTRO: Billions of years ago, life on Earth was mostly just large slimy mats of microbes living in shallow water. Sometimes, these microbial communities made carbonate minerals that over many years cemented together to become layered limestone rocks called stromatolites. They are the oldest evidence of life on Earth. But the fossils don’t tell researchers the details of how they formed.
Today, most life is supported by oxygen. But these microbial mats existed for a billion years before oxygen was present in the atmosphere. So what did life use instead? Our team of geologists, physicists and biologists had found hints in fossilized stromatolites that arsenic was the chemical of choice for ancient photosynthesis and respiration. But modern-day versions of these microbial communities still live on Earth today. Perhaps one of these used arsenic and could offer proof for our theory?
So we joined a surveying expedition of Chilean and Argentinian scientists to look for living stromatolites in the extreme conditions of the High Andes. In a small stream deep in the Atacama Desert, we found a big surprise. The bottom of the channel was bright purple and made of stromatolite-building microbial mats that thrive in the complete absence of oxygen. Just as the clues we’d found in ancient fossils suggested, these mats use two different forms of arsenic to perform photosynthesis and respiration. Our discovery offers the strongest evidence yet for how the oldest life on Earth survived in a pre-oxygen world... (MORE)
https://www.mirror.co.uk/science/undergr...d-22754288
INTRO: Mars may be teeming with life in lakes underneath its south pole, according to new research. A complex system of multiple undergound lakes has been discovered at the south pole. The "patchwork" has been likened to those on Antarctica - where strange shrimp-like anthropods, tentacled jellyfish and swimming sea cucumbers hang out.
The finding suggests water is a permanent feature below the surface of the Red Planet. Co-lead author Professor Elena Pettinelli said: "The presence of sub-glacial lakes could have important consequences for astrobiology - and the presence of habitable niches on Mars."
They are rich in salt - which lowers water's freezing point. This would keep it liquid at temperatures as low as -74 C. The international team detected three reservoirs of various sizes a mile down under a thick layer of ice - and confirmed the existence of a much larger fourth. They may have been there for more than four billion years - and be home to extremophiles that can survive the harshest conditions.
It's also possible aerobes or anaerobes are there - organisms that thrive with and without oxygen, respectively. The study published in Nature Astronomy is based on an analysis of data from the Mars Express orbiter... (MORE)
Ancient microbial life used arsenic to thrive in a world without oxygen
https://theconversation.com/ancient-micr...gen-146533
INTRO: Billions of years ago, life on Earth was mostly just large slimy mats of microbes living in shallow water. Sometimes, these microbial communities made carbonate minerals that over many years cemented together to become layered limestone rocks called stromatolites. They are the oldest evidence of life on Earth. But the fossils don’t tell researchers the details of how they formed.
Today, most life is supported by oxygen. But these microbial mats existed for a billion years before oxygen was present in the atmosphere. So what did life use instead? Our team of geologists, physicists and biologists had found hints in fossilized stromatolites that arsenic was the chemical of choice for ancient photosynthesis and respiration. But modern-day versions of these microbial communities still live on Earth today. Perhaps one of these used arsenic and could offer proof for our theory?
So we joined a surveying expedition of Chilean and Argentinian scientists to look for living stromatolites in the extreme conditions of the High Andes. In a small stream deep in the Atacama Desert, we found a big surprise. The bottom of the channel was bright purple and made of stromatolite-building microbial mats that thrive in the complete absence of oxygen. Just as the clues we’d found in ancient fossils suggested, these mats use two different forms of arsenic to perform photosynthesis and respiration. Our discovery offers the strongest evidence yet for how the oldest life on Earth survived in a pre-oxygen world... (MORE)
