Stop teasing me, Universe - and show me the aliens already!
In this case it’s highly unlikely that there out there, that close, existing simultaneous with us. 4 billion years ahead of us...they’re either long dead or non-existing.
Two potentially life-friendly planets found orbiting a nearby star
61–70 of 391 posts
Re: Two potentially life-friendly planets found orbiting a nearby star
#62Earlier quoted context omitted.
> I know it's nearby on galactic scales but it's practically about 450,000 Earth years away with current technology :-) If we had the political will, the Orion design could get people there in, what, 200 years, and that's with '70s technology.
Imagine being the child born on the ship on a crash course to this new planet.
And imagine you're the first ship to arrive only to find out
a) that the planet is not habitable and there were some wrong assumptions about it
b) that the planet is already occupied by a different form of life and there's no warm welcome to us
Re: Two potentially life-friendly planets found orbiting a nearby star
#63Earlier quoted context omitted.
"However, more recent research is somewhat more optimistic." I am deeply skeptical of that "recent research", which AFAIK is "computer models, where we have zero capability to verify the computer models against even a single data point". The incentives to keep kicking the computer model until it provides something publishable, with no countervailing force provided by real data to be explained by the model, are just t…
How did we verify the earlier theories?
We check them against data.
I have no objection to computer models; I object to computer models that can't be checked against data.
Cosmologists run a lot of models, to do things like try to determine the effects of dark matter on the universe. Such models are intrinsically problematic since they have to have resolution on the order of hundreds or thousands of lightyears on a side, or have to work with universes much smaller than the real one, or something that means the simulation is by necessity literally several dozen orders of magnitude smaller than the real universe (consider both the timestep and spatial dimensions).
But they can check the result by looking up in the sky and seeing if it matches. This allows them to overcome the problematic nature of the models and use them to say real things.
One wonders what exciting cosmological papers proposing all sorts of amazing and outlandish theories as a result of some computer model of the universe have been suppressed by the fact that they didn't correspond to the sky at all. I guarantee you that some very amazing simulations have been run that produced incredible results of great interest, whose only crime was that they completely failed to match the universe.
We don't have a tidally locked planet that has an active atmosphere in our solar system to look at.
Re: Two potentially life-friendly planets found orbiting a nearby star
#64life friendly planets and new battery tech are just fantasy.
Re: Two potentially life-friendly planets found orbiting a nearby star
#65Re: Two potentially life-friendly planets found orbiting a nearby star
#66"just 12 light-years away" I love the "just". I know it's nearby on galactic scales but it's practically about 450,000 Earth years away with current technology :-)
> I know it's nearby on galactic scales but it's practically about 450,000 Earth years away with current technology :-) If we had the political will, the Orion design could get people there in, what, 200 years, and that's with '70s technology.
You could get their corpses there, sure.
Re: Two potentially life-friendly planets found orbiting a nearby star
#67How common are "life-friendly" planets (Let's say: on a ratio of Life-Friendly Planet:Non Life-Friendly Planet)? And is there any way to check if life-friendly planets contain life without actually going there?
As other commenters have said, we don't have the tools to see that far yet, so it's only through a miracle of math, physics, and engineering that we can deduce the size, distance from the star, and atmospheric composition of exoplanets from variations in the brightness and color of a distant star over time. The James Webb telescope should help, but because of the nature of the technique our observations are constrained to solar systems that are perfectly aligned with ours, such that the planets pass directly in front of the star relative to the observer. It's possible that we can survey enough of those stars to get a rough idea of the ratio of life friendly planets, but we'll likely never know for sure. Maybe conditions for supporting life are correlated with alignment to the galactic plane!
Re: Two potentially life-friendly planets found orbiting a nearby star
#68Earlier quoted context omitted.
Imagine being the child born on the ship on a crash course to this new planet.
And imagine you're the first ship to arrive only to find out a) that the planet is not habitable and there were some wrong assumptions about it b) that the planet is already occupied by a different form of life and there's no warm welcome to us
Sounds like the premise of Aurora! Which definitely turned me off the idea of multi generational starship travel. It's not ethical.
Re: Two potentially life-friendly planets found orbiting a nearby star
#69Earlier quoted context omitted.
Imagine being the child born on the ship on a crash course to this new planet.
And imagine you're the first ship to arrive only to find out a) that the planet is not habitable and there were some wrong assumptions about it b) that the planet is already occupied by a different form of life and there's no warm welcome to us
[deleted]
Re: Two potentially life-friendly planets found orbiting a nearby star
#70I was under the impression that planets to be life-friendly have to be close to their red dwarf star to a point they'll be tidally locked (one side always light other night), meaning their atmosphere would freeze on the dark side and planet would end up without an atmostphere.
This was indeed the prevailing wisdom for some time. However, more recent research is somewhat more optimistic. Even an atmosphere 10% as dense as that of earth can circulate heat to the dark side efficiently enough, given the right composition. The night side temperature could be within the parameters required to sustain some form of life. Furthermore, tidal locking is dependent on oceans and atmosphere, and can tak…
Or a day-night-day-penumbra-umbra-penumbra cycle. The primary-facing side would get maximum light just before entering the penumbra, experience total darkness in the umbra, and get some light directly from the star and some reflected from the primary from the time it exits the umbra to the time it re-enters. Every day would have a full stellar eclipse at noon. Every night would see the primary cycle from waxing half through full to waning half. The space-facing side would have an ordinary day-night cycle with the same period as its orbital period around its primary.