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Possible life on Venus?
cdev:
There are birds, swifts, that spand most but not all of their lifecycle flying, that live on Earth, in Europe.
But to lay their eggs and hatch them they have to return to Earth. They even sleep while they are flying.
--- Quote from: EEVblog on September 17, 2020, 06:15:09 am ---The interesting thing is apparently there is a strata layer in the clouds on Venus that would allow human to actually survive with just supplemental oxygen. Pressures and temperatures are apparently very similar to earth and suitable for humans.
No idea what it takes to stay at a certain height in the atmosphere though?
--- End quote ---
460voltclub:
If a single cell is found on a planet people call it life, then why are fetuses not considered life when in the first few day after fertilization there are thousands of cells under going changes and exhibiting life.
Halcyon:
Let's keep this discussion on-topic and not make it political, particularly when what you're saying isn't accurate in the slightest.
Rick Law:
--- Quote from: donotdespisethesnake on September 15, 2020, 07:30:28 pm ---The sticking points I have with the venus-life hypothesis is in order to survive the 80% sulphuric acid clouds, either:
1) the life forms have a completely different basis to Earth (e.g a non-carbon base). That would be an even more shocking discovery.
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--- End quote ---
Unless we water down the definition of life significantly, chances are, life will be carbon based.
Silicon has been a source of great excitement. But detailed analysis of the chemistry puts silicon based life form rather unlikely on earth due to certain limitations. Those limitations applies on earth and elsewhere since it is just part of silicon's chemistry. The limitations are:
(1) Silicon oxide is solid. For us, carbon dioxide being gas and soluble in water, we can expel it easily. Silicon dioxide on the other hand is "virtually insoluble" below (about) 40C. For silicon based life form, that means it has to be rather hot (high Atmospheric pressure can help). An alternative is a method of disposal. Where energy is needed within a part the body, that energy-needing part will need to evolve a way to collect and dispose of solid waste before it can depend on having energy. Can do but much more complex thus much less likely.
(2) Handedness with carbon molecules allow one enzyme/molecule to "key-lock" like fit to another enzyme/molecule. This aids bio-molecules with their ability "regulate" (fit/not-fit) processes precisely and efficiently. Silicon molecules with handedness is far fewer than carbon molecules with handedness. So, choices are limiting and there by functions are more limited.
(3) Even with the "Stanley Kipping Award in Silicon Chemistry" encouraging silicon molecule development, many silicon molecules needed for life has not been successfully made. Thermodynamic data confirm these carbon molecules analogs using silicon are "often unstable".
(4) The chain reactions of carbon molecule chemistry to make life work has limitations: each reaction has a temperature and pH range. For the entire chain to work, all reaction must fit within a range that the entire chain can work. The silicon-analog chain reactions can't all fit within the same range from one reaction to another. So any needed chain reactions will be necessarily a shorter chain or can't chain at all.
So, in X-Files, silicon based life form makes an exciting story. In real life, it is kind of hard to see silicon working with some degree of complexity.
Reference:
The points above are summarized from Raymond Dessy's (Scientific Americans' Feb 1998) article on Silicon life. Raymond Dessy is a professor of Chemistry at Virginia Polytechnic Institute and State University in Blacksburg, Va.
You can get to the article here:
https://www.scientificamerican.com/article/could-silicon-be-the-basi/
EDIT: corrected a missing "not" - "has yet been made" corrected to "has not been made" in point #3.
BrianHG:
This second one nails it...
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