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Two potentially life-friendly planets found orbiting a nearby star

nationalgeographic.com

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Re: Two potentially life-friendly planets found orbiting a nearby star

#41

Post by modzu »

jerf wrote: post #17
sushibowl wrote: post #13

Earlier quoted context omitted.

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…

"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…

well even our deep space observations are largely computed. nobody has "seen" these 2 planets at all ;)

Re: Two potentially life-friendly planets found orbiting a nearby star

#42

Post by bencollier49 »

api wrote: post #32
petercooper wrote: post #20

"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 :-)

Look into Project Orion. With thermonuclear bombs you could hit 8% c, which would get you there in "only" 150-200 years including acceleration and deceleration time. That is still beyond humans with present day life spans, but extend life span to ~1000 years or go full AI and you can totally ride the "devil's pogo stick" to stars Fusion rockets would probably be better. I mention Orion because we sort of know how to…

Is that subjective time for the crew or objective time? Is there much of a difference at 8% c?

Re: Two potentially life-friendly planets found orbiting a nearby star

#44

Post by bencollier49 »

skribbj wrote: post #37
TwoNineA wrote: post #4

I 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.

I'm sorry, I'm not at all educated in this subject and I might be misunderstanding what you are saying, but isn't Earth the perfect example to argue against this? We're a life-friendly planet that isn't tidally locked?

I think this is just for red dwarf stars, not ones like sol.

Re: Two potentially life-friendly planets found orbiting a nearby star

#45

Post by pault »

TeMPOraL wrote: post #36
petercooper wrote: post #31

Earlier quoted context omitted.

I doubt I'm alone in this, but I do find it simultaneously amusing and depressing how mind bogglingly big the universe (or even the galaxy) is. It's clear that discovering entirely new levels of physics will be necessary to stand a chance of going anywhere.

You're not alone. I grew up reading and watching a lot of sci-fi. Today I recognize that most of it was garbage in terms of physics, but I'm still saddened that the universe isn't that easy - we can't just hop on a space cruise ship and do a tour of a nearby nebula...

Going to Mars may be routine some day, though!

Re: Two potentially life-friendly planets found orbiting a nearby star

#46

Post by acidburnNSA »

lmm wrote: post #30
petercooper wrote: post #20

"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.

Are you talking about the propulsion system where a series of nuclear explosions push the vessel along?

https://en.wikipedia.org/wiki/Project_Orion_(nuclear_propuls...

Re: Two potentially life-friendly planets found orbiting a nearby star

#47

Post by api »

bencollier49 wrote: post #42
api wrote: post #32

Earlier quoted context omitted.

Look into Project Orion. With thermonuclear bombs you could hit 8% c, which would get you there in "only" 150-200 years including acceleration and deceleration time. That is still beyond humans with present day life spans, but extend life span to ~1000 years or go full AI and you can totally ride the "devil's pogo stick" to stars Fusion rockets would probably be better. I mention Orion because we sort of know how to…

Is that subjective time for the crew or objective time? Is there much of a difference at 8% c?

Little time dilation at 8%, so not a big difference.

Re: Two potentially life-friendly planets found orbiting a nearby star

#48

Post by jbattle »

skribbj wrote: post #37
TwoNineA wrote: post #4

I 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.

I'm sorry, I'm not at all educated in this subject and I might be misunderstanding what you are saying, but isn't Earth the perfect example to argue against this? We're a life-friendly planet that isn't tidally locked?

It has to do with the class of star. This star is so cool that the only way for the planet to be warm enough to support life is for the planet to be really close to the star. I don't really understand tidal locking but I think it happens vastly faster at closer orbits - because there is a stronger gravitational gradiant closer to the parent body.

Re: Two potentially life-friendly planets found orbiting a nearby star

#49

Post by krisroadruck »

vkaku wrote: post #27

Stop teasing me, Universe - and show me the aliens already!

Check out the Dyson Dilemma for a well-reasoned theory as to why it is a high probability that there is no space-faring intelligent life anywhere in our galaxy or even perhaps our super-cluster.

https://www.youtube.com/watch?v=QfuK8la0y6s

Re: Two potentially life-friendly planets found orbiting a nearby star

#50

Post by tictoc »

lmm wrote: post #30
petercooper wrote: post #20

"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.

Imagine being the child born on the ship on a crash course to this new planet.
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