how different would life be if we were on a tidally locked planet? would we develop sleep? would life even develop on the other side of the planet where it's always dark?
how different would life be if we were on a tidally locked planet? would we develop sleep?
visible wavelength of light would be redder than earthlings' (the star is red dwarf)
leaves are perpendicular to the ground (the star is always at dawn/dusk position)
birds wouldn't travel (there's no season)
vulnerable to temperature change (there's no season)
>no season
Maybe no seasons based on orbital rotation, but there could easily be much long term seasons based on the planets massive winds creating huge weather patterns the planet. Seasons are a cyclical pattern of local weather/climate conditions, it isn't bound to any singular cause. Even if it was a binary wet/dry season dynamic, that'd still count.
Does anyone know any good books on the subject?
>would we develop sleep?
It would be 1000000000000x easier evolutionary to just not be sensitive to light for the purposes of sleep, and instead sleep purely on a circadian or fatigue basis. Nature has not found a way to sustain a large (bigger than microscopic) creature for any sustainable duration of time without having it sleep. And even everything else, including plants, undergo periods of dormancy to accomplish things similar to what sleep accomplishes.
With the right conditions I think life could evolve. The question of sleep really is the more interesting one.
i saw a space anime that had a tidally locked planet, it was pretty neat, basically all the ayylmaos lived in twilight zone band
Title of the anime?
kanata no astra or astra lost in space
its a sci-fi, mystery, but mostly mystery
the super storms would still make the middle part of the planet unlivable for like the 90% of the earth animal population
How does it keep an atmosphere if half of the planet isn't receiving any water?
just by gravity. water isn't necessary to keep the atmosphere.
see Venus.
I think it has more to do with Venus having an actual magnetic field to keep solar wind from stripping away the atmosphere. Gravity on Mars for example is about 62% of Earth but it has <1% atmospheric density.
I know about the convection of mantle or cores that generates magnetic field, which saves gaseous planetary component from blown off by solar radiation.
I can say
- the condition where such convection keeps working for a long time is simply that the mass of the planet is sufficiently huge.
ex. Venus and Earth have convection keep working for 460 million years, while any planet or satellite smaller than them has its internal comopnents already cooled and solidified.
- still doesn't have to do with the liquid body on surface in the first place
Venus barely has a magnetic field, the reason why Venus has thick atmosphere is because its escape velocity is almost as high as Earth's as well as being much higher than the root mean squared speeds of Nitrogen and Carbon Dioxide
Martian surface gravity is only 38% of Earth's and has about half the escape velocity
These details about Venus are important. Add one more: the lack of a moon. Venus loses a lot more atmosphere than Earth every day ... or, it would ... EXCEPT that Earth's Moon helps strip even more off. Venus has a heavy, thick atmosphere mostly due to its mass & associated gravity (and, its composition is a literal Hellscape of toxic heat and sulfuric acid rain). Earth would have a much heavier atmosphere, and it would probably never have become primarily oxygen/nitrogen, if we didn't have a Moon helping to strip off some of it for several billion years.
So, add another factor into this discussion. Planets tidally locked to their star that have a moon or don't have a moon will be radically different if all other factors are more or less the same. Depending on their mass, they will retain different compositions of atmosphere, as well as different amounts. And that's assuming they are chemically very similar to Earth to generate an ~80% nitrogen/~20% oxygen mix.
Water can be converted to other forms. On Venus, a lot of it's combined with sulfur to form sulfuric acid. Due to the lower gravity and the weak magnetic field, hydrogen gets stripped off the top layers of atmosphere as soon as they are free, before they get a chance to chemically combine with something else again. Again, another factor that's important: due to being much closer to the Sun, Venus experiences a much stronger Solar wind than Earth, so the lightest atmospheric components that rise up get stripped, leaving heavier elements & chemicals behind to form whatever atmosphere they can. Water, BTW, is relatively light and also gets directly stripped. There is Venusian water captured by Earth that's been carried into our orbit by the Solar winds.
> if we didn't have a Moon helping to strip off some of it
Earth's atmopshere would have a lot of nitrogen atmosphere regardless, give that It was present in it's second atmosphere. Te large Oxygen on the other hand is biotic in origin.
>Again, another factor that's important: due to being much closer to the Sun, Venus experiences a much stronger Solar wind than Earth, so the lightest atmospheric components that rise up get stripped, leaving heavier elements & chemicals behind to form whatever atmosphere they can.
interesting. i remember learning all this "oh venus could have been an earth too but something le happened on it!" if the solar winds part is true, then it's just not in the same habitable zone as earth and there was never any chance of life there...at least not life beyond microscopic levels
how you know all that,do you have a libary or something i can check out ?
>t. Geologist, Geochemist, Environmental Geology
I'm ridiculously overeducated in planetary sciences. About 160 undergraduate credits worth, plus other academic & research work and ongoing interests. Also a bit out of date, although the fundamentals still hold true. Don't really know the most recent two decades worth of cutting edge research. But, did spend years studying how planets form, especially some astrophysics on stars and star system formation. And how galaxies coalesce. We study a LOT of theoretical shit so we can understand how the Earth works, and every other planet in our Solar system. The dynamics of atmospheres and their interaction with gravity, magnetic fields, solar winds, types of stars, moons, chemical evolution of atmospheres and oceans ... all are essential to grokking how the Earth works. And that's before we get into the physics of molten rock and iron and gas giants.
It's fun stuff. Earth is an incredibly rare type of planet; there's about a million unique factors that came together just right to make us how we are. Any of those could have been slightly off and Earth would be as lifeless as the Moon. Tidally locked (and semi-locked) planets are a fascinating and essential part of those studies.
For ITT, I propose considering a large Venus-to-Earth sized moon that is tidally locked to a gas giant such as Saturn, but maybe closer to the orbit of Mars around a Sun-like star. Life would be vastly more possible & even likely there, and a far more fascinating planetary environment that still has very large extremes.
And, yeah, it would be very different from Earth life. This ain't Star Trek. Unfortunately, no frickable catgirls.
thanks for answering me,was keeping the tab in background
>it would be very different from Earth life
Convergent evolution disagrees. There are physically optimal forms for certain types of motion, which selection will trend towards given a certain kind of environment. How they're made chemically, psychologically, sensorily may differ greatly, but form will likely be at least somewhat familiar.
Convergent evolution isn't a theory, it's barely defensible as a hypothesis based upon survivor bias from a sample size of one: Earth. Evolution is divergent by its fundamental nature.
Fluid dynamics disagree.
why is Wauf full of morons
I dunno but you asking that question on Wauf doesn't make much sense either since nobody was talking about anime.
>Unfortunately, no frickable catgirls.
once again things fall short where it actually matters…
>For ITT, I propose considering a large Venus-to-Earth sized moon that is tidally locked to a gas giant such as Saturn, but maybe closer to the orbit of Mars around a Sun-like star. Life would be vastly more possible & even likely there, and a far more fascinating planetary environment that still has very large extremes.
This is actually pretty cool. The day/night and month/year cycles would be wildly complex, and I like the idea that such a "planet" might be habitable by humans. Trying to imagine Saturn in the night sky, which would be almost as bright as daytime. Plus maybe 20 or 30 other moons all moving about and causing insane tidal patterns.
> tidally locked to a gas giant such as Saturn but maybe closer to the orbit of Mars around a Sun-like star
I understand why moons like this could be potential earth analogs, especially given that tidal heating from the planet would off set the decrease in solar irradiance, but any habital moon close enough to a gas giant to have anything close to an earth like day is going to get bathed in the radiation of the planet's van Allen belts.
If geogay is still in this thread, what would the minimum requirements for a planet to harbor life? And then what would be the requirements for microscopic-only life vs macroscopic organisms, say up to the volume of a human?
im pretty sure its just liquid water, large cellular life is kinda impossible without exposure to a star because just like deep sea life, their lifestyle is reliant on bacteria doing whatever it is they do at underwater volcanoes to inject energy into the system,
>geogay still in this thread
>minimum requirements for a planet to harbor life?
That's very hotly debated. There are a vast array of conditions to consider & how they interact with each other, then you have to define what is life. Most people say water & oxygen, but Earth had little free oxygen when life first developed. With water argument requires all conditions supply water in sufficient quantities, and any other thing (such as oxygen) will determine many of the conditions. I've seen very convincing arguments that life could develop in a methane ocean in the complete lack of the presence of oxygen (one of the moons of Jupiter, I forget which one. It had methane volcanoes when one of our probes passed by).
Every condition you can imagine, including all the ones in this thread like radiation and temperature and tides ... however you want define the possibility of life, define the conditions that will support it. You can get really science fiction fast on it. Could life exist inside a star? David Brin wrote a book called Sundiver that explores that very question. Brin is no hack, he's a very successful sci fi writer who happens to be a professor of astrophysics.
Read up on the conditions on Mars & Venus in wikipedia. It is strongly believed that life can exist on both those planets (and the methane oceans of one of Jupiter's moons). Now imagine life can probably live in much harsher conditions. Perhaps Mercury? I doubt it, but wouldn't be shocked. More like mildly surprised. And a bit excited. That would open massive possibilities all over the universe IF that turned out to be true.
Also, distinguish between "harbor" life and "develop &/or evolve" life. Very different things.
>Could life exist inside a star?
The questions might sound moronic, but all life needs is self replication and this can happen inside a star for all we know.
>Most people say water & oxygen
Most people don't deserve water & oxygen.
There is also the fact that Venus has active volcanism which makes up for the gases that manage to escape
Venus is also virtually tidal locked. Its day is longer than its year. But the temperature is pretty much the same everywhere, poles, equator, night or day, all the same.
That is a shitload of landmass, like 10% water on the surface.
Instructive to read about Mercury:
https://en.wikipedia.org/wiki/Mercury_(planet)
Try to imagine what type of life could develop and adapt to those conditions, including the lack of axial tilt.
A "tidally locked" planet would still be a class of planets that can have various conditions. You'll need to define a number of those. Does it have a magnetic field? How large is the planet? How far is it from its sun? What type of star does it orbit? Does it have axial tilt? Does its orbit approach a circle, or is it more eccentric like Mercury or Pluto? What atmospheric composition?
Overall, the tl;dr answer is: VERY different. If life could form at all, the extreme conditions would require extreme adaptability, and most life on such a world would only be able to survive in regions they are adapted to, they would not be able to travel into other regions. Think in terms of deep sea organisms on Earth trying to adapt to or visit the Sahara desert, but 1000 or 10,000 times worse.
One side of the planet would be locked in cold as deep as the dark side of the Moon, the other side would be a blast furnace with lakes of liquid iron. Vaporized lead (and other toxic metals) from the hot side would travel into the boundary zones and precipitate as rain and dust. The entire planet would have significant cadmium, arsenic, lead, tin, copper, etc. incorporated into everything like water, ice, atmosphere, soil, etc. Any life would have to develop to survive in that ... and those are just a couple of the thousands of incredibly toxic & hostile conditions to mention.
Oh, did we mention the storms? Because perpetual super storms as the heat & cold sides exchange atmosphere.
Wouldn't there be huge storms in between the two sides?
yes
Life only exists on the one planet G*d created: Earth. Fruitless to speculate otherwise
Who created God?
Be forewarned, you can't just claim God created God, that makes absolutely no sense.
Irrelevant question. G*d always was and will be. He's the Eternal Being. I don't need to wonder who created Him. See Psalm 13:10
>biblecuck trying to derail a potentially interesting thread
Yeah. It couldn't be a atheist shitposting.
ummm thats not as fun for me to meme about so im going to ignore it
there's too many posts just like that on Wauf for it to be all atheists shitposting.
yeah falseflagging is probably a better word for it in the case of that board
Election tourists. When christies get uppity just call them fat, it's statistically more likely to be correct than it is for any other religion.
I think the planet would be permanently sterilized by the time the star cooled to that point and tides and the accompanying geothermal activity are probably needed for abiogenesis anyways
>G*d
israelite spotted
Say His name
Do you think He ever wonders
>dude wtf am I doing here
tidally locked
= close to a star
= highly likely the star is a red dwarf
= plants would look black, since they absorb red and blue
>evolve to absorb most of all the visible light on earth BUT the most abundant color
What did plants mean by this?
I guess you can blame that on green algae being the best at conquering the land and eventually becoming plants. Like that tiktaalik meme but focusing on the plants next to tiktaalik.
we had plants that did absorb different spectrum sections.
but turn out that blocking green was most efficient.
plants aren't bottlenecked by light input, but rather by nutrient exchange.
CO2, etc.
Would plants evolve to absorb green if they appeared on a more distant planet like Mars or some gas giant moon?
It's entirely possible. However, their equivalent for chlorophyll (as we know & currently understand it) would have to be different than Earth chlorophyll. Also, in our Solar system, the spectrum of our Sun determines some of the best/better parts of the spectrum for energy that can be captured & converted to food. So, chlorophyll-like photosynthesis in our Solar system will probably resemble the process we see on Earth. Other stars would likely force the evolution of something more radically different.
Apart from all that, the definition of "plant" might get pretty stretched & distorted off Earth. The equivalent of "plant" in other locations could (or even probably would) be different enough it would be an entirely new kingdom of life form, as different from Earth plants as fungus or animals are.
For emergency reasons. Plants are conscious.
> = highly likely the star is a red dwarf
non sequitur
do you think white dwarves or neutron stars work?
at least, every tidally locked planet with a main sequence star is a scorched rock or a hot jupiter.
Assuming that life is thriving in that middle bit, then some form of life is almost certainly surviving in the extremes.
Extremophile microorganisms sure, but nothing macroscopic could ever survive on the cold side, and I'm fairly sure the hot would be a no go as well. It would make amazing legends for the sapient species on that planet though, finally being able to conquere the blazing west or the frigid east. This would be some killer word building actually.
It's not really hard to survive the cold tho, penguins sleep in the open at down to -40 degrees(in both systems) every night, and we're at a really hot age, It's not unimaginable that during the glaciation even more extreme lows were commonplace, and better adapted lifeforms almost certainly lived in there.
Also since half of the planet is void of water but the warm ring is full of it I would assume the cold side has big below-ice oceans, which is even easier to survive in.
Dude you are not taking into account how fricking frigid a place that never sees any sunlight would be. The coldest temp ever recorded (naturally) on earth was at Vladivostok station, and that was about -30 celcius. On antarctica, the only life on the surface would be a few species of prokaryotes such as cyanobacteria which hyperspecialized to the frigid temperatures while undergoing photosynthesis constantly for half the year. For reference, the cold side of mercury reaches temps as low as -180 celcius and there is never any sunlight so there will be no photosynthesis. Subsurface oceans sure could have life sure, but we're talking about surface life here, and absolutely nothing could survive in such a harsh environment for any extended period of time.
that's interesting, I wonder how wind would work in an atmosphered planet, maybe if the wind is strong enough energy could be delivered from the middle to the poles
>about -30 celsius
You're about 60 degrees off. Coldest temp on Earth was about -90C. It regularly gets to -40C in winter where I live.
>It would make amazing legends for the sapient species on that planet though, finally being able to conquere the blazing west or the frigid east. This would be some killer word building actually.
Humans have been in both colder and hotter places without actually aiming for it, if you have specialized enough clothes (spacesuits, or surfacesuits in this case) you can be in both without changing clothes
Maybe there would be economic reasons to try and figure out how far people would go in there like solar energy or freshwater refineries. There could be horror stories of ice mining stations in the cold side running out of power as the inhabitants slowly freeze to death. Maybe more primitive people's would considers wandering into the endless deserts as a sort of ritualistic walking into the gates of heaven, or they could even execute people by forcing them to walk into the uninhabitable wastelands. Someone really ought to get on this.
There would definitely be wicked strong storms ravaging the planet almost constantly, it would definitely make an impact on the temperatures. Maybe there would be temporary sorta tendrils of habitability with common storm patterns that melt the ice or cool the sun scorched earth.
I imagine the mythos would involve a lot of battles between the Gods like how we treated the sun and moon. So humanity would be considered in the middle of the great two warring Gods whose storms fight for dominance, life could be treated as more of an unintended consequence rather than a gift.
Alternately the two gods are constantly trying to convince Humanity to go over to their side, but neither is trustworthy.
pea brained morons