EDG,
Thank you for the response. I have no idea why no one else asked any questions, but if you are willing, I have a few.
Basically, we were discussing about habitable planets, how to get them, and what the stellar implications were. My basic position was that for a planet to have an nitrogen/oxygen atmosphere (i.e. atmosphere codes 2-9;D-F, or at least 4-9) requires some kind of biosphere that took a really, really long time to develop. If a world had no life, the oxygen wouldn’t be in the atmosphere. Since that level of oxygen takes so long and takes at least some kind of life, that means such a planet really needs a reasonably stable star, meaning likely one of F G K M main sequence. Obviously, the ancients can influence this, but there *were* only 400 of them (even if they controlled billions of subjects, there were only 400 of them), and even then there is only so much they can do over their 10,000 – 20,000 years of activity.
Questions around this, are:
- Is the above even remotely close to correct?
- Granted, we only have a sample of 1, but is it feasible for primitive life to generate an appreciable oxygen atmosphere over 300,000 years? Or would it take millions of years?
- If a world had a type 6 atmosphere, but lost its entire biosphere, how long would it take to lose its oxygen?
- Assume a world with a thick layer of frozen volatiles outside the a star’s habitable zone. Assume it is as ideal for this situation as possible. When the star enters its giant phase and the planet finds itself in the habitable zone, would there be enough time for life and oxygen to develop before the star burns out?
Again, I apologize for taking over a week to respond, but RL has been busy. Thank you for any chance you have to respond.
Mike West
Thank you for the response. I have no idea why no one else asked any questions, but if you are willing, I have a few.
Basically, we were discussing about habitable planets, how to get them, and what the stellar implications were. My basic position was that for a planet to have an nitrogen/oxygen atmosphere (i.e. atmosphere codes 2-9;D-F, or at least 4-9) requires some kind of biosphere that took a really, really long time to develop. If a world had no life, the oxygen wouldn’t be in the atmosphere. Since that level of oxygen takes so long and takes at least some kind of life, that means such a planet really needs a reasonably stable star, meaning likely one of F G K M main sequence. Obviously, the ancients can influence this, but there *were* only 400 of them (even if they controlled billions of subjects, there were only 400 of them), and even then there is only so much they can do over their 10,000 – 20,000 years of activity.
Questions around this, are:
- Is the above even remotely close to correct?
- Granted, we only have a sample of 1, but is it feasible for primitive life to generate an appreciable oxygen atmosphere over 300,000 years? Or would it take millions of years?
- If a world had a type 6 atmosphere, but lost its entire biosphere, how long would it take to lose its oxygen?
- Assume a world with a thick layer of frozen volatiles outside the a star’s habitable zone. Assume it is as ideal for this situation as possible. When the star enters its giant phase and the planet finds itself in the habitable zone, would there be enough time for life and oxygen to develop before the star burns out?
Again, I apologize for taking over a week to respond, but RL has been busy. Thank you for any chance you have to respond.
Mike West