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+--- Thread: Earth's instant life + Pluto's nitrogen "sea" geology + Mars' weird spidery veins (/thread-1851.html)
Earth's instant life + Pluto's nitrogen "sea" geology + Mars' weird spidery veins - C C - Jan 12, 2016
"Life on Earth May have Started Almost Instantaneously" --UCLA (Today's Most Popular)
http://www.dailygalaxy.com/my_weblog/2016/01/life-on-earth-may-have-started-almost-instantaneously-ucla-todays-most-popular.html
EXCERPT: [...] The UCLA scientists have found evidence that life likely existed on Earth at least 4.1 billion years ago -- 300 million years earlier than previous research suggested. The discovery indicates that life may have begun shortly after the planet formed 4.54 billion years ago. [...] The new research suggests that life existed prior to the massive bombardment of the inner solar system that formed the moon's large craters 3.9 billion years ago. "If all life on Earth died during this bombardment, which some scientists have argued, then life must have restarted quickly," said Patrick Boehnke, a co-author of the research and a graduate student in Harrison's laboratory....
Pluto's Large Nitrogen Ice 'Sea' Probably Formed from Giant Impact, Scientists Say
http://www.americaspace.com/?p=90543
EXCERPT: “We did not predict that a small planet like Pluto could still be active and would not have completely cooled off,” said Alan Stern, New Horizons Principal Investigator....
These Spidery 'Veins' On Mars Are Just Plain Weird
http://www.space.com/31583-spider-mars-veins-dry-ice-photo.html
EXCERPT: This photo, captured by NASA's Mars Reconnaissance Orbiter in February 2009, shows spidery troughs on the Red Planet likely formed by the sublimation of carbon dioxide. Nobody knows yet whether or not Mars has ever hosted life, but the Red Planet itself looks strangely alive in a newly released NASA photo....
RE: Earth's instant life + Pluto's nitrogen "sea" geology + Mars' weird spid... - Yazata - Jan 13, 2016
(Jan 12, 2016 08:38 PM)C C Wrote: The UCLA scientists have found evidence that life likely existed on Earth at least 4.1 billion years ago -- 300 million years earlier than previous research suggested. The discovery indicates that life may have begun shortly after the planet formed 4.54 billion years ago. [...] The new research suggests that life existed prior to the massive bombardment of the inner solar system that formed the moon's large craters 3.9 billion years ago. "If all life on Earth died during this bombardment, which some scientists have argued, then life must have restarted quickly," said Patrick Boehnke, a co-author of the research and a graduate student in Harrison's laboratory....
This is why I'm increasingly inclined to think that life didn't originate on Earth.
Where it came from is anyone's guess.
A source (Mars?) within the solar system would have most of the same difficulties as origin on Earth, since I don't think that Mars is older than the Earth and it would still have been subject to the early asteroid bombardment. The advantage of an origin within our solar system would be that it's easier to imagine how life could have gotten from there to here.
My own speculation runs more to an interstellar source, a source on some much older unknown explanet. The difficulty with an interstellar origin would be in explaining how life made the journey. If life drifted through interstellar space for long periods of time, in a freeze-dried state perhaps, how much likelihood is there that DNA and complex organic molecules could have withstood cosmic radiation?
RE: Earth's instant life + Pluto's nitrogen "sea" geology + Mars' weird spid... - C C - Jan 14, 2016
(Jan 13, 2016 08:41 PM)Yazata Wrote: This is why I'm increasingly inclined to think that life didn't originate on Earth. Where it came from is anyone's guess. A source (Mars?) within the solar system would have most of the same difficulties as origin on Earth, since I don't think that Mars is older than the Earth and it would still have been subject to the early asteroid bombardment.
The Mars proponents argue that the early red planet had some surface geochemistry (like oxidized molybdenum) and other factors thought to be crucial to abiogenesis, which Earth "supposedly" lacked at the time.
Quote: The advantage of an origin within our solar system would be that it's easier to imagine how life could have gotten from there to here. My own speculation runs more to an interstellar source, a source on some much older unknown explanet. The difficulty with an interstellar origin would be in explaining how life made the journey. If life drifted through interstellar space for long periods of time, in a freeze-dried state perhaps, how much likelihood is there that DNA and complex organic molecules could have withstood cosmic radiation?
In the past, I've encountered this or that published or filmed report on a few microrganisms on Earth which have been tested in ways that exposed how they could have durability or dormant capacity in the extreme conditions of space for very long periods. An odd thing about panspermia (from both intersolar and interstellar sources) should be the potential of Earth still receiving "exotic" microbial life after and over the course of billions of years. Perhaps due to being at such a primitive and passive stage when it arrives, they would be repressed or eliminated by competitive native forms before they ever achieved a foothold in the biosphere.