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Proxima Centauri has a Earth-like planet

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Re: Proxima Centauri has a Earth-like planet

#21

Post by BlanketLogic »

deftnerd wrote: post #13

It might have an earth-like planet in terms of orbit and composition, but I highly doubt that it would have life on it. Proxima Centauri is a flare-type star, meaning that it it unpredictably brightens across its entire spectrum from infrared to x-ray. A planet would have to have a really thick atmosphere to protect against that, and a thick atmosphere can easily run away like Venus. Without a thick atmosphere, any b…

> Without a thick atmosphere, any burgeoning life would have to deal with random bursts of energy that could cause damage to that lifes equivalent of genetic coding.

Is having a thick atmosphere a necessary condition for life?

Is it not possible for a mutation to result in a 'thick skinned' life form - one that relies on its exo-skeleton/skin to withstand the drastic changes? Or a color-changing 'plant' that evolved to do ultra-fast-photo synthesis when needed and move into a dormant mode, when not?

Such a thing would allow such plants and animals to move out of the seas and go onto dominate the land. (Assuming, of course that there is life underwater)

Re: Proxima Centauri has a Earth-like planet

#22

Post by kyriakos »

dogma1138 wrote: post #17
whatshisface wrote: post #14

Earlier quoted context omitted.

There's no thick atmosphere like ten feet of water. The frequency absorption of water has a small window around visible light and a sold wall around it. [1] Maybe the danger of building telescopes on the surface (and the rapid attenuation of their home medium) is why they haven't built any radios to chat with us. ;) [1] http://hyperphysics.phy-astr.gsu.edu/hbase/chemical/watabs.h...

Techonlogical society can't develop under water.

Life doesn't always mean intelligent advanced civilisation.

Re: Proxima Centauri has a Earth-like planet

#23

Post by SerLava »

breuleux wrote: post #18
erdevs wrote: post #12

Earlier quoted context omitted.

I don't know. Fermi paradox has never bothered me too badly. Between possible great filters (behind and/or ahead of us), the time and distance involved in species discovery and travel, and the fact we're still apparently pretty early in the universe's lifespan ... it seems reasonable to me that we may be some combination of rare and early. So, Group I seems reasonable. One potential "great filter" always stood out as…

I think it makes sense for an intelligent civilization not to expand, if you consider the problem of synchronizing over vast interstellar distances. If it takes years to exchange messages and resources back and forth between two colonies, it will be slow and costly to keep them on the same page. That means they will likely evolve independently and may become competitors. In other words, colonies lacking resources ins…

>In other words, colonies lacking resources inside the expansion wave would start attacking their own neighbours,

This could be possible if interstellar travel was very, very, very easy. But in all likelihood the last place you're going to want to find resources is on a tiny speck of rock 20 lightyears away.

Re: Proxima Centauri has a Earth-like planet

#24

Post by mirkules »

dogma1138 wrote: post #20
whatshisface wrote: post #19

Earlier quoted context omitted.

You can have culture, tools and electrochemistry underwater.

You can't have fire, basic tools maybe, more than that not really. Also doing chemistry underwater is pretty neat impossible. Sure we can do it today, but incremental development is very unlikely. There is a good chance that any technological species we need will be quite close to us because there are certain criteria that are likely to be met which are pretty universal.

You can have fire underwater, take for example Magnesium torches. Knowing what we know now about technology, it is difficult to imagine getting to this point underwater. But imagine a life form that lived in these conditions from the beginning, and perhaps having tools and doing chemistry may not be so far fetched after all.

Re: Proxima Centauri has a Earth-like planet

#26

Post by sigil »

thangalin wrote: post #6
Jedd wrote: post #5

I appreciate it's 100% speculative, as we are stuck with a sample set of only one, but I'm increasingly of the belief that we're rare (as opposed to first or fucked [1]). Heavily swayed by a recent reading of Nick Lane's excellent book on Mitochondria[2]. The fact that even our nearest neighbour probably has an earth-like planet is, from this angle, a bit depressing. [1] http://waitbutwhy.com/2014/05/fermi-paradox.ht…

The Percolation Theory reasons that Earth might linger in an uninteresting part of the Milky Way: its galactic backwaters. See: * [1998] http://www.geoffreylandis.com/percolation.htp * [2014] https://arxiv.org/abs/1404.0204

That Landis paper is great, thanks.

Re: Proxima Centauri has a Earth-like planet

#28

Post by dogma1138 »

mirkules wrote: post #24
dogma1138 wrote: post #20

Earlier quoted context omitted.

You can't have fire, basic tools maybe, more than that not really. Also doing chemistry underwater is pretty neat impossible. Sure we can do it today, but incremental development is very unlikely. There is a good chance that any technological species we need will be quite close to us because there are certain criteria that are likely to be met which are pretty universal.

You can have fire underwater, take for example Magnesium torches. Knowing what we know now about technology, it is difficult to imagine getting to this point underwater. But imagine a life form that lived in these conditions from the beginning, and perhaps having tools and doing chemistry may not be so far fetched after all.

Again you are extrapolating the wrong things.

Can't have incremental development underwater.

Magnesium torches have thier own oxidizer.

Find a way to refine magnesium underwater.

I can imagine a lot of things but it doesn't mean it's possible.

Technological life forms are going to be pretty similar to us. Sight, fine motor skills and various other aspects are going to be pretty close.

Re: Proxima Centauri has a Earth-like planet

#29

Post by dogma1138 »

kyriakos wrote: post #22
dogma1138 wrote: post #17

Earlier quoted context omitted.

Techonlogical society can't develop under water.

Life doesn't always mean intelligent advanced civilisation.

No it doesn't, but it has to be intelligent to build telescopes read the parent comment :)

Re: Proxima Centauri has a Earth-like planet

#30

Post by germinalphrase »

dogma1138 wrote: post #28
mirkules wrote: post #24

Earlier quoted context omitted.

You can have fire underwater, take for example Magnesium torches. Knowing what we know now about technology, it is difficult to imagine getting to this point underwater. But imagine a life form that lived in these conditions from the beginning, and perhaps having tools and doing chemistry may not be so far fetched after all.

Again you are extrapolating the wrong things. Can't have incremental development underwater. Magnesium torches have thier own oxidizer. Find a way to refine magnesium underwater. I can imagine a lot of things but it doesn't mean it's possible. Technological life forms are going to be pretty similar to us. Sight, fine motor skills and various other aspects are going to be pretty close.

Why must they be similar to us?

For instance, I completely accept that a sightless entity, as we have sight, could develop a technological culture.

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