Earth is a strange planet for this reason. Because Earth's core is so large in proportion to it's diameter it has a stronger magnetic field at the surface and is denser than a planet formed through normal gravitational accretion. If Earth was any lighter, it would have ended up like Mars, unable to hold it's atmosphere.
Earth is probably at the very low end of habitability due to its size. Most exobiologists look at what we call super Earth's because they are more likely to have complex life.
Another cool fact is that the further you go back in time the shorter the day lasted on Earth and the closer the moon was. 65 million years ago a day was around 23 to 23.5 hours long and the moon was 2 to 3 thousand km closer.
And do you know there’s a very narrow window where planets have the right mass/density to allow for escape velocity?
So maybe larger worlds are more habitable but life on it is trapped in their gravity wells. And lighter planets don’t normally have cores large enough to allow for magnetic fields strong enough to protect their atmospheres.
I'm pretty sure it's in Asimov's Foundation series where a character is actively looking for Earth, which has long been abandoned and lost, and the character sees Earth's statistics ie moons, size, density etc and exclaims that there is no such planet, no planet that small has a moon that big etc. it very much highlights how rare our planet could be.
I have no idea what people like you expect. The books as written are completely impossible to translate into a coherent series. At best, an anthology series might work, but Asimov is so thin on character depth and decent dialogue that it would still not seem true to the books.
I think the series is great. They figured out decent enough solutions to continuity and casting an otherwise unadaptable series. Try to enjoy things. Makes life less shitty.
I haven’t seen the series but I like your critique on the book. I only read the first one and it felt like such a drag. And I really respect Isaac Asimov but Foundation did not interest me.
I'll admit I mostly driven by my fascination for how much of that book was outright pillaged to make the modern foundations of a bunch of fairly well known scifi series.
Kind of like how the setting of Dune played a huge part in the early concepts of Star Wars.
There are many other ways to leave the planet, it's not just chemical rockets, there is Project Orion which has the concept of using nuclear bombs detonating behind rockets in a controlled manner to send them to space for example, if they are intelligent life desperate to leave their star system knowing that they are going to die in it's red giant state, they would go out by even doing that!.
Wait what. What do you mean "allow" for escape v? Like if the planet had more gravity couldn't it be escaped with more force? Is it because the curvature also increases (decreases?)? I'd still feel like saying it'd be impossible for life to escape it doesn't feel right while simultaneously acknowledging that science doesn't care what "feels right"
If the Earth was a little bigger it would be very difficult if not impossible to go to orbit with chemical rockets. Then you would need something like nuclear rockets or magnetic rail launch systems but those are still pretty sci fi so the question is if a species on such a planet would ever discover space flight
Right, so that's what I figured was meant. Our current technology wouldn't be able to do a task it wasn't designed for...fortunately despite not needing to solve that issue ourselves, we still have come up with ideas that would work though haven't actually created them. It seems absurd to think a technologically advanced society wouldn't be able to add a little oomph to their rockets above where we are now if you gave them a couple hundred years, especially if their society valued science unlike ours
If their was too massive, gravity would make escape velocity less feasible, so smart species could still remain “trapped” on their planet. Is it possible? Probably, but it’s dramatically harder and becomes less “worth it”.
I imagine intelligent life on heavier planets would eventually escape the atmosphere by taking advantage of the (likely) more dense atmosphere and things more akin to SSTOs rather than just rockets like we do.
Sort of tangential, but would the increase in gravity mean a higher 'pressure' of the surface crust, thus the processes that allow for material to turn into oil would be affected?
Like...all other things being equal but dialing up Earth's surface gravity ~20%, could we expect there to be any different amount of oil, or maybe even diamonds or other things formed under pressure, compared to Earth as we know it today?
•
u/ShaggyCan 10h ago edited 10h ago
Earth is a strange planet for this reason. Because Earth's core is so large in proportion to it's diameter it has a stronger magnetic field at the surface and is denser than a planet formed through normal gravitational accretion. If Earth was any lighter, it would have ended up like Mars, unable to hold it's atmosphere. Earth is probably at the very low end of habitability due to its size. Most exobiologists look at what we call super Earth's because they are more likely to have complex life. Another cool fact is that the further you go back in time the shorter the day lasted on Earth and the closer the moon was. 65 million years ago a day was around 23 to 23.5 hours long and the moon was 2 to 3 thousand km closer.