Timeline for Is a desert planet with a small habitable area possible?
Current License: CC BY-SA 4.0
24 events
| when toggle format | what | by | license | comment | |
|---|---|---|---|---|---|
| Jul 8 at 22:24 | comment | added | Mon | @John Yep. That's the basic problem. A lack of detail in the question. As described it's a 'desert planet', no oceans or any other large bodies of water mentioned. So you have to assume there are none. | |
| Jul 8 at 17:10 | comment | added | John | @FrançoisJurain then there are no oceans. its one or the other | |
| Jul 8 at 10:29 | comment | added | François Jurain | @John Let there be sandtrouts from Arrakis; let them be fruitful, and multiply, and fill the sand in the landmass, and gather the waters therein. Problem solved. | |
| Jul 6 at 23:49 | comment | added | John | @FrançoisJurain if it is 75% ocean it can't have the rest be desert, way to much water in the atmoppshere. | |
| Jul 6 at 22:14 | comment | added | Mon | @Francois Jurain. Yes that would solve the problem (mostly) But the author doesn't mention the existence of oceans or for that matter any other large bodies of water or ice in his question. As I noted in another comment here somewhere. His description of his world lacks critical details that would make answering his question a lot easier. As he literally describes it? There's not much wriggle room for a solution. | |
| Jul 6 at 19:53 | comment | added | user121330 | "After nine days I let the horse run free 'Cause the desert had turned to sea There were plants and birds and rocks and things There was sand and hills and rings … The ocean is a desert with its life underground And a perfect disguise above ..." | |
| Jul 6 at 16:13 | comment | added | Andrew Alexander | Could be another process that somehow creates oxygen too, it doesn't necessarily need to be biological, but could instead be geological. Not sure what that process would be, but there are alternative to just a biology-based oxygen environment - even if that is how ours came to be | |
| Jul 6 at 13:01 | comment | added | vsz | Oxygen could have been produced many million years ago but the planet desertified merely thousands of years ago. Oxygen will last a long long time, even if not being produced right now. | |
| Jul 6 at 1:08 | comment | added | Mon | @Msalters the process of photosynthesis involves the breakdown of water molecules into their component oxygen and hydrogen atoms. The oxygen atoms are surplus to requirements and mostly get released into the environment. The hydrogen gets combined with carbon dioxide to form carbohydrates (plants source of energy). So no water? No plants, or algae. No plants? No photosynthesis. No photosynthesis? No free oxygen. I'm afraid it does make sense. | |
| Jul 5 at 13:25 | comment | added | MSalters | This answer makes little sense. O2 is produced by plants and consumed by animals. Without water, 99% of the planet does not change O2 levels. This answer assumes the O2 production is reduced to 1%, but ignores that the consumption is also reduced to 1%. Plant life cannot liberate O2 from SiO2 (sand), only from CO2. | |
| Jul 5 at 13:08 | comment | added | François Jurain | If a planet has 75% ocean and 25% landmass, the latter all desert except a wee bit of oasis, does it count as a 100% desert planet? If yes, then let the ocean produce all the oxygen you need. | |
| Jul 4 at 21:46 | history | edited | Mon | CC BY-SA 4.0 |
deleted 4 characters in body
|
| Jul 4 at 16:57 | comment | added | Slarty | @Mon Ah - yes! I somehow missed that. You a quite right. | |
| Jul 4 at 15:59 | comment | added | Chris H | Most deserts on Earth have some plants photosynthesising away and producing oxygen. With minimal animal life (in the desert, but also in the oasis because of its size) a reasonable level could be maintained with far lower production. The bigger problem on this planet is more likely to be getting even the little water they need to the desert plants - if there are no seas for it to evaporate from you'll have trouble. For that matter where does the water for the small fertile region come from? Ice caps provide one possibility, or hyper-saline (dead) seas | |
| Jul 4 at 12:54 | comment | added | Mon | @Jedediah Possibly. The real problem (and there's no criticism intended when I say this BTW) is that the author doesn't go into that any detail in their post about how life evolved on their planet in the first place i.e. their planet, as described as literally being 'desert world'. Full stop, end of story. Sure, life could have evolved there before it desertified but that's not stated in the original post as an option. All you have is "I have a desert planet etc!" | |
| Jul 4 at 12:41 | comment | added | Jedediah | If you had alien chemotrophes (say, vent feeders in underground seas), you might rationalize low but adequate oxygen levels, as a byproduct of "alien processes". | |
| Jul 4 at 12:21 | history | edited | Mon | CC BY-SA 4.0 |
added 101 characters in body
|
| Jul 4 at 12:13 | history | edited | Mon | CC BY-SA 4.0 |
added 101 characters in body
|
| Jul 4 at 9:59 | comment | added | Mon | @Slarty The only problem is that the original post specifically stipulated that the world in question was a 'desert planet' i.e. unless otherwise stated it had no large bodies of liquid water (in proportion to it's total surface area). You see the problem. The author would need to specify that their world had oceans and seas in the past. And even then once those oceans etc freeze/evaporate? Sustaining any complex surface ecology becomes problematic. | |
| Jul 4 at 6:55 | comment | added | Slarty | Oxygen is certainly highly important, but whether land based life is required is an open question. Photosynthetic bacteria first evolved in the sea ~ 3 billion years ago and produced vast amounts of oxygen that cleared the oceans of huge quantities of iron (as the oxide), after that started to outgas and oxidize the land crust. Multicellular land plants only arrived about 1 billion years ago. Perhaps sea based photosynthetic organisms could have eventually produced the level of oxygen that we see today, It may have taken longer. But less land also means fewer land animal oxygen consumers. | |
| Jul 4 at 5:30 | comment | added | Mon | For you world the best idea might be to make it a bit like a gaint Mars. Lots of ice trapped at the Poles, vast cold tundra and steppe biomes (look them up) and numerous small lakes/seas dotting the equator like the Caspian and Black Seas or the Great lakes etc which support other richer biomes like forests along their coasts. The great steppes only experience rain in the summer. So from space you would see first one hemisphere then the other 'green' as warmer weather melted some ice & rain/rivers flowed followed by a 'dry' season when it freezes again. Its about the best I can think of. | |
| Jul 4 at 5:14 | comment | added | Mon | No probs. Now you talking talking about another topic. Alternate (alien) organic chemistries. There are chemophine species (Not reliant on oxygen) that live in places like deep sea volcanic vents for example but the vast majority of life on Earth is dependent on oxygen/carbon chemistry. | |
| Jul 4 at 4:41 | comment | added | Breadsauce4 | That's actually really interesting, so thanks for the answer. I was also thinking that there would be some plants and small animals in the desert sections of the planet, but again it might not produce enough oxygen. What other gasses do you think would be produced, and could an alien species breathe that gas. For example, alien life could theoretically survive with breathing hydrogen. I know that hydrogen will probably not be very abundant in this planet, but my question still stands. Thanks! | |
| Jul 4 at 3:22 | history | answered | Mon | CC BY-SA 4.0 |