Bitcoin Forum
June 18, 2024, 09:16:12 PM *
News: Latest Bitcoin Core release: 27.0 [Torrent]
 
   Home   Help Search Login Register More  
Pages: « 1 2 [3]  All
  Print  
Author Topic: Why Habitable Exoplanets Might Mean Humanity Is Doomed  (Read 4157 times)
duhosnyul
Sr. Member
****
Offline Offline

Activity: 266
Merit: 250



View Profile
April 27, 2014, 04:49:01 AM
Last edit: April 27, 2014, 05:11:21 AM by duhosnyul
 #41

I read before that there are billions of stars in our galaxy. And only 1,000,000 systems located in goldilocks zone like our sun that can support life. Our galaxy has a diameter of 100,000 light years. It its calculated that the nearest possible civilization is within 1000 light years. That civilization can be a million ahead of us or million years from now. The possiblity of each civilization to contact each other has a very small chance.

We are using radiowaves the same speed as light. If we are contacting a civilization from 1000 light years away. It take 1000 earth years for our message to reach them. If they reply immediately assuming they are listening to us it would take another 1000 earth years, for their message to reach us. And we don't have the machine yet and the energy needed would be tremendous. And how would we communicate them?
 



Energycoin. eD5Kv8NxNAgge58bbyJfZpANDDJg2G7uid
Freebiescoin- Free Distribution
FCsxVbuZzEekqY9q9voNZHps7fnqndRfuF
HQXH1995
Newbie
*
Offline Offline

Activity: 1
Merit: 0


View Profile
April 27, 2014, 05:23:36 AM
 #42



https://i.imgur.com/BV44hP9.jpg
An artist's concept of Kepler-186f, discovered in April 2014.

Last week, scientists announced the discovery of Kepler 186f, a planet 492 light years away in the Cygnus constellation. Kepler 186f is special because it marks the first planet almost exactly the same size as Earth orbiting in the “habitable zone” – the distance from a star in which we might expect liquid water, and perhaps life.

What did not make the news, however, is that this discovery also slightly increases how much credence we give to the possibility of near-term human extinction. This because of a concept known as the Great Filter.

The Great Filter is an argument that attempts to resolve the Fermi Paradox: why have we not found aliens, despite the existence of hundreds of billions of solar systems in our galactic neighborhood in which life might evolve? As the namesake physicist Enrico Fermi noted, it seems rather extraordinary that not a single extraterrestrial signal or engineering project has been detected (UFO conspiracy theorists notwithstanding).

This apparent absence of thriving extraterrestrial civilizations suggests that at least one of the steps from humble planet to interstellar civilization is exceedingly unlikely. The absence could be caused because either intelligent life is extremely rare or intelligent life has a tendency to go extinct. This bottleneck for the emergence of alien civilizations from any one of the many billions of planets is referred to as the Great Filter.

Are we alone?

What exactly is causing this bottleneck has been the subject of debate for more than 50 years. Explanations could include a paucity of Earth-like planets or self-replicating molecules. Other possibilities could be an improbable jump from simple prokaryotic life (cells without specialized parts) to more complex eukaryotic life – after all, this transition took well over a billion years on Earth.

Proponents of this “Rare Earth” hypothesis also argue that the evolution of complex life requires an exceedingly large number of perfect conditions. In addition to Earth being in the habitable zone of the sun, our star must be far enough away from the galactic center to avoid destructive radiation, our gas giants must be massive enough to sweep asteroids from Earth’s trajectory, and our unusually large moon stabilizes the axial tilt that gives us different seasons.

These are just a few prerequisites for complex life. The emergence of symbolic language, tools and intelligence could require other such “perfect conditions” as well.

Or is the filter ahead of us?

http://mashable.com/2014/04/23/habitable-planets-human-extinction/

Vod
Legendary
*
Offline Offline

Activity: 3738
Merit: 3098


Licking my boob since 1970


View Profile WWW
April 27, 2014, 05:24:10 AM
 #43

I read before that there are billions of stars in our galaxy.

Hundreds of billions.    Wink

https://nastyscam.com - featuring 13 years of OGNasty bitcoin scams     https://vod.fan - advanced image hosting - coming sooner than you think!
Fatpony
Member
**
Offline Offline

Activity: 74
Merit: 10


View Profile
April 27, 2014, 11:04:52 AM
 #44

Humans have not been listening to the "space" long enough to take that time into consideration and a prof that aliens do not exist. Let's put it like this. If i live on an island in some ocean with 100 other people and the closest land is 6.000km in any direction, chances that me and my "friends" will find any other life are slim ( considering we still havent discovered planes, boats that can cross oceans ). In that case my enitre life I would thing that we are the only humans.....

But now we have detected exo planets similar to Earth.  And that will continue, now that we know how to do it.  After a while, we'll have - let's say - a list of 100 such planets.  We can aim DIRECTIONAL recievers at those points.

Right now we are just randomly pointing antennas around hoping to maybe pick something up.  With radio that doesn't work too well.  You'd never hear or talk to the Mars rovers unless you had extremely narrow directional antennas.

And obviously to listen to another star system, the problem is that much worse.  We do have some good guesses as to what frequencies to listen on, but have not to this time, known WHERE.

And how will that help? There are billions of planets in our galaxy alone, what are the chances that those planets would have intelligent life? Less then winning a lotto 3x in a row. You are forgetting many things, and one of them evolution and technological develepment. Being a planet that can sustain life doesnt equal intellignet life has yet evolved or survived, or taht species is capable to emit radio into space. And we as humans have been brought to near extinction many, many times... And dont forget that human made radio wave has traveled about 100 LY so far ( furthest ), so if lets say there is an intelligent life on that Exoplanet listening to our part of the galaxy ( pointing radio waves to our planet ) he wont detect ANYTHING.

You misunderstand.  I suggest not that an ET would hear anything from us, but that signalling from, to and between ET would be by narrow beam communications.  Of what type?  Does not really matter.  Narrow beam requires knowing where to point, so ET(planet 937) would point at what he considered habitable planets.  Because of some details of chemistry, water is most suitable, so he would have had a beam pointed at Earth.

How would you detect it?   You'd crank a directional antenna around in turn between planet 0...999, and when you hit 937, you might pick it up.  If you did, you just hit the jackpot.  Because that repeating broadcast from ET would contain the details of how, where and when to communicate.

I know what are you trying to say but you need to take into calculation time since it plays HUGE part in detecting intelligent life. If that planet 973 has intelligent life that is at same level of technological level as we are then we wont be hearing form them in centuries. Radio waves travel with the same speed as light so if they are 900 LY away and they sent signal 100 years from now we wont hear it in another 800 years. And if they are millions of years ahead we probably will never figure out they exist. But what if that planet has intelligent life but they are in stone age?
Paya
Sr. Member
****
Offline Offline

Activity: 334
Merit: 250


View Profile
April 27, 2014, 12:50:49 PM
Last edit: April 27, 2014, 01:15:06 PM by Paya
 #45

Thing that should also be taken into consideration is the fact that we are very, very young technical civilization. Earth is hosting life for 4 billions of years, homo sapiens may have been around for 200.000 years, and yet we've discovered radio 100 years ago and radio astronomy just 80 years ago. Hell, all our recorded history is barely 6000 years old. That's really miniscule timespan when put into the cosmic scales. Plenty of interesting events may have happened which went unnoticed or in best case misunderstood, as they may be happening right now too.
Spendulus
Legendary
*
Offline Offline

Activity: 2898
Merit: 1386



View Profile
April 27, 2014, 05:16:48 PM
 #46

Humans have not been listening to the "space" long enough to take that time into consideration and a prof that aliens do not exist. Let's put it like this. If i live on an island in some ocean with 100 other people and the closest land is 6.000km in any direction, chances that me and my "friends" will find any other life are slim ( considering we still havent discovered planes, boats that can cross oceans ). In that case my enitre life I would thing that we are the only humans.....

But now we have detected exo planets similar to Earth.  And that will continue, now that we know how to do it.  After a while, we'll have - let's say - a list of 100 such planets.  We can aim DIRECTIONAL recievers at those points.

Right now we are just randomly pointing antennas around hoping to maybe pick something up.  With radio that doesn't work too well.  You'd never hear or talk to the Mars rovers unless you had extremely narrow directional antennas.

And obviously to listen to another star system, the problem is that much worse.  We do have some good guesses as to what frequencies to listen on, but have not to this time, known WHERE.

And how will that help? There are billions of planets in our galaxy alone, what are the chances that those planets would have intelligent life? Less then winning a lotto 3x in a row. You are forgetting many things, and one of them evolution and technological develepment. Being a planet that can sustain life doesnt equal intellignet life has yet evolved or survived, or taht species is capable to emit radio into space. And we as humans have been brought to near extinction many, many times... And dont forget that human made radio wave has traveled about 100 LY so far ( furthest ), so if lets say there is an intelligent life on that Exoplanet listening to our part of the galaxy ( pointing radio waves to our planet ) he wont detect ANYTHING.

You misunderstand.  I suggest not that an ET would hear anything from us, but that signalling from, to and between ET would be by narrow beam communications.  Of what type?  Does not really matter.  Narrow beam requires knowing where to point, so ET(planet 937) would point at what he considered habitable planets.  Because of some details of chemistry, water is most suitable, so he would have had a beam pointed at Earth.

How would you detect it?   You'd crank a directional antenna around in turn between planet 0...999, and when you hit 937, you might pick it up.  If you did, you just hit the jackpot.  Because that repeating broadcast from ET would contain the details of how, where and when to communicate.

I know what are you trying to say but you need to take into calculation time since it plays HUGE part in detecting intelligent life. If that planet 973 has intelligent life that is at same level of technological level as we are then we wont be hearing form them in centuries. Radio waves travel with the same speed as light so if they are 900 LY away and they sent signal 100 years from now we wont hear it in another 800 years. And if they are millions of years ahead we probably will never figure out they exist. But what if that planet has intelligent life but they are in stone age?
Well, let me give you a more plausible case.  100,000 years ago numerous advanced civilizations in the galaxy set up transmitters pointed to identified life-capable exo planets.  Some died or were wiped out, but others continued the transmissions using the same formula   The transmitters were to run indefinitely and transmit a repeating broadcast with specific info on where to look in the sky for information broadcasts.  All broadcasts are one direction, transmit only.  Like our DirectTV satellites, you might say.

We discover exoplanets, we point our sensitive antenna at them and suck up a couple of broadcasts.  Decode them, perhaps build the necessary equipment, and VOILA!  We are hooking into the galactic DirectTV, baby!  Cool!

Now, you see, "time lag" does not really matter.

Some years/centuries/millenia later, perhaps we choose to set up our own transmitter.
TaunSew
Hero Member
*****
Offline Offline

Activity: 756
Merit: 506


View Profile
April 27, 2014, 05:40:32 PM
 #47

TV noise is not TV Noise - it is remnants of the Space Reptilians and their intergalactic communication network.  Shsss... psssfttt... gsssssk...   We just assumed it was background noise the entire time because it was there since the beginning.

There ain't no Revolution like a NEMolution.  The only solution is Bitcoin's dissolution! NEM!
Fatpony
Member
**
Offline Offline

Activity: 74
Merit: 10


View Profile
April 27, 2014, 06:23:20 PM
 #48

Humans have not been listening to the "space" long enough to take that time into consideration and a prof that aliens do not exist. Let's put it like this. If i live on an island in some ocean with 100 other people and the closest land is 6.000km in any direction, chances that me and my "friends" will find any other life are slim ( considering we still havent discovered planes, boats that can cross oceans ). In that case my enitre life I would thing that we are the only humans.....

But now we have detected exo planets similar to Earth.  And that will continue, now that we know how to do it.  After a while, we'll have - let's say - a list of 100 such planets.  We can aim DIRECTIONAL recievers at those points.

Right now we are just randomly pointing antennas around hoping to maybe pick something up.  With radio that doesn't work too well.  You'd never hear or talk to the Mars rovers unless you had extremely narrow directional antennas.

And obviously to listen to another star system, the problem is that much worse.  We do have some good guesses as to what frequencies to listen on, but have not to this time, known WHERE.

And how will that help? There are billions of planets in our galaxy alone, what are the chances that those planets would have intelligent life? Less then winning a lotto 3x in a row. You are forgetting many things, and one of them evolution and technological develepment. Being a planet that can sustain life doesnt equal intellignet life has yet evolved or survived, or taht species is capable to emit radio into space. And we as humans have been brought to near extinction many, many times... And dont forget that human made radio wave has traveled about 100 LY so far ( furthest ), so if lets say there is an intelligent life on that Exoplanet listening to our part of the galaxy ( pointing radio waves to our planet ) he wont detect ANYTHING.

You misunderstand.  I suggest not that an ET would hear anything from us, but that signalling from, to and between ET would be by narrow beam communications.  Of what type?  Does not really matter.  Narrow beam requires knowing where to point, so ET(planet 937) would point at what he considered habitable planets.  Because of some details of chemistry, water is most suitable, so he would have had a beam pointed at Earth.

How would you detect it?   You'd crank a directional antenna around in turn between planet 0...999, and when you hit 937, you might pick it up.  If you did, you just hit the jackpot.  Because that repeating broadcast from ET would contain the details of how, where and when to communicate.

I know what are you trying to say but you need to take into calculation time since it plays HUGE part in detecting intelligent life. If that planet 973 has intelligent life that is at same level of technological level as we are then we wont be hearing form them in centuries. Radio waves travel with the same speed as light so if they are 900 LY away and they sent signal 100 years from now we wont hear it in another 800 years. And if they are millions of years ahead we probably will never figure out they exist. But what if that planet has intelligent life but they are in stone age?
Well, let me give you a more plausible case.  100,000 years ago numerous advanced civilizations in the galaxy set up transmitters pointed to identified life-capable exo planets.  Some died or were wiped out, but others continued the transmissions using the same formula   The transmitters were to run indefinitely and transmit a repeating broadcast with specific info on where to look in the sky for information broadcasts.  All broadcasts are one direction, transmit only.  Like our DirectTV satellites, you might say.

We discover exoplanets, we point our sensitive antenna at them and suck up a couple of broadcasts.  Decode them, perhaps build the necessary equipment, and VOILA!  We are hooking into the galactic DirectTV, baby!  Cool!

Now, you see, "time lag" does not really matter.

Some years/centuries/millenia later, perhaps we choose to set up our own transmitter.

And why do you think that after 100,000 years ago they are still searching for intelligent life or that if they are wiped out/extinct their radio equipment is still active after all those years?  Time lag is crucial, you can't neglect that and say oh well who cares. Assume that some alien race 100,000 years "older" and more advanced then us, why d you think they will search for intelligent life so low on a technological level? The difference between us and that alien race in technology is so great that that alien race wouldn't be interested in "talking". And even if they are interested they would be looking for signs of current communication not possible one in xyz years. They find exoplant, listen fo few week, they dont hear anything and move along, same as we are doing. And if they are so advanced that they discovered how to harness the power of Tachyons ( assuming they exist ) there is no chance for us to speak to them or detect something we are not even sure exists, and if you think alien race so advanced would use sublight speed communication, then thats just wrong.
Spendulus
Legendary
*
Offline Offline

Activity: 2898
Merit: 1386



View Profile
April 27, 2014, 07:31:33 PM
 #49

Humans have not been listening to the "space" long enough to take that time into consideration and a prof that aliens do not exist. Let's put it like this. If i live on an island in some ocean with 100 other people and the closest land is 6.000km in any direction, chances that me and my "friends" will find any other life are slim ( considering we still havent discovered planes, boats that can cross oceans ). In that case my enitre life I would thing that we are the only humans.....

But now we have detected exo planets similar to Earth.  And that will continue, now that we know how to do it.  After a while, we'll have - let's say - a list of 100 such planets.  We can aim DIRECTIONAL recievers at those points.

Right now we are just randomly pointing antennas around hoping to maybe pick something up.  With radio that doesn't work too well.  You'd never hear or talk to the Mars rovers unless you had extremely narrow directional antennas.

And obviously to listen to another star system, the problem is that much worse.  We do have some good guesses as to what frequencies to listen on, but have not to this time, known WHERE.

And how will that help? There are billions of planets in our galaxy alone, what are the chances that those planets would have intelligent life? Less then winning a lotto 3x in a row. You are forgetting many things, and one of them evolution and technological develepment. Being a planet that can sustain life doesnt equal intellignet life has yet evolved or survived, or taht species is capable to emit radio into space. And we as humans have been brought to near extinction many, many times... And dont forget that human made radio wave has traveled about 100 LY so far ( furthest ), so if lets say there is an intelligent life on that Exoplanet listening to our part of the galaxy ( pointing radio waves to our planet ) he wont detect ANYTHING.

You misunderstand.  I suggest not that an ET would hear anything from us, but that signalling from, to and between ET would be by narrow beam communications.  Of what type?  Does not really matter.  Narrow beam requires knowing where to point, so ET(planet 937) would point at what he considered habitable planets.  Because of some details of chemistry, water is most suitable, so he would have had a beam pointed at Earth.

How would you detect it?   You'd crank a directional antenna around in turn between planet 0...999, and when you hit 937, you might pick it up.  If you did, you just hit the jackpot.  Because that repeating broadcast from ET would contain the details of how, where and when to communicate.

I know what are you trying to say but you need to take into calculation time since it plays HUGE part in detecting intelligent life. If that planet 973 has intelligent life that is at same level of technological level as we are then we wont be hearing form them in centuries. Radio waves travel with the same speed as light so if they are 900 LY away and they sent signal 100 years from now we wont hear it in another 800 years. And if they are millions of years ahead we probably will never figure out they exist. But what if that planet has intelligent life but they are in stone age?
Well, let me give you a more plausible case.  100,000 years ago numerous advanced civilizations in the galaxy set up transmitters pointed to identified life-capable exo planets.  Some died or were wiped out, but others continued the transmissions using the same formula   The transmitters were to run indefinitely and transmit a repeating broadcast with specific info on where to look in the sky for information broadcasts.  All broadcasts are one direction, transmit only.  Like our DirectTV satellites, you might say.

We discover exoplanets, we point our sensitive antenna at them and suck up a couple of broadcasts.  Decode them, perhaps build the necessary equipment, and VOILA!  We are hooking into the galactic DirectTV, baby!  Cool!

Now, you see, "time lag" does not really matter.

Some years/centuries/millenia later, perhaps we choose to set up our own transmitter.

And why do you think that after 100,000 years ago they are still searching for intelligent life or that if they are wiped out/extinct their radio equipment is still active after all those years?  Time lag is crucial, you can't neglect that and say oh well who cares. Assume that some alien race 100,000 years "older" and more advanced then us, why d you think they will search for intelligent life so low on a technological level? The difference between us and that alien race in technology is so great that that alien race wouldn't be interested in "talking". And even if they are interested they would be looking for signs of current communication not possible one in xyz years. They find exoplant, listen fo few week, they dont hear anything and move along, same as we are doing. And if they are so advanced that they discovered how to harness the power of Tachyons ( assuming they exist ) there is no chance for us to speak to them or detect something we are not even sure exists, and if you think alien race so advanced would use sublight speed communication, then thats just wrong.

And why do you think that after 100,000 years ago they are still searching for intelligent life or that if they are wiped out/extinct their radio equipment is still active after all those years?


Some might, some might not. 

Time lag is crucial, you can't neglect that and say oh well who cares.


Time lag is not crucial it is irrelevant for one way transmission.  It is relevant for two way conversations, yes.

Assume that some alien race 100,000 years "older" and more advanced then us, why d you think they will search for intelligent life so low on a technological level?


Broadcasting is different than searching.

The difference between us and that alien race in technology is so great that that alien race wouldn't be interested in "talking".


Right.  So Europeans were not interested in talking with American Indians.  Wrong....

And even if they are interested they would be looking for signs of current communication not possible one in xyz years. They find exoplant, listen fo few week, they dont hear anything and move along, same as we are doing.

Assume that some number of ET are/have been doing this.  So there exists something like a bunch of cable TV channels and data feeds they can tune into.  If one goes dark, then flip channels.

And if they are so advanced that they discovered how to harness the power of Tachyons ( assuming they exist ) there is no chance for us to speak to them or detect something we are not even sure exists, and if you think alien race so advanced would use sublight speed communication, then thats just wrong.


I mentioned that the basic repeating broadcast sent the life-capable exoplanets would be in radio or light narrow beam comm channel.  Why?  Well, because that's the basic signal by which the universe presents itself to our senses.  There have been studies made of the likely/most probable frequencies which would be used which make sense.

So yeah, the initial message received might be how to build the 'more advanced receiver' that was required to actually link into the galactic network.
herzmeister
Legendary
*
Offline Offline

Activity: 1764
Merit: 1007



View Profile WWW
April 28, 2014, 03:14:33 PM
 #50

The answer to the Fermi Paradox is that we're living in a computer simulation, obviously.  Smiley

http://www.simulation-argument.com/simulation.html

Indeed, we're alone in this simulation. Other solar systems and planets are just a technical trick of the program, designed to be just a red herring. They're projected far enough away from us so that the limits and borders of our world are somewhat believable for us.

https://localbitcoins.com/?ch=80k | BTC: 1LJvmd1iLi199eY7EVKtNQRW3LqZi8ZmmB
Wilikon (OP)
Legendary
*
Offline Offline

Activity: 1176
Merit: 1001


minds.com/Wilikon


View Profile
April 28, 2014, 04:44:22 PM
 #51

The answer to the Fermi Paradox is that we're living in a computer simulation, obviously.  Smiley

http://www.simulation-argument.com/simulation.html

Indeed, we're alone in this simulation. Other solar systems and planets are just a technical trick of the program, designed to be just a red herring. They're projected far enough away from us so that the limits and borders of our world are somewhat believable for us.

but if it is a simulation as some said, what would be the real size of the "universal pixel"?
Spendulus
Legendary
*
Offline Offline

Activity: 2898
Merit: 1386



View Profile
April 28, 2014, 04:45:12 PM
 #52

The answer to the Fermi Paradox is that we're living in a computer simulation, obviously.  Smiley

http://www.simulation-argument.com/simulation.html

Indeed, we're alone in this simulation. Other solar systems and planets are just a technical trick of the program, designed to be just a red herring. They're projected far enough away from us so that the limits and borders of our world are somewhat believable for us.

10 other possibilities...

http://io9.com/11-of-the-weirdest-solutions-to-the-fermi-paradox-456850746
herzmeister
Legendary
*
Offline Offline

Activity: 1764
Merit: 1007



View Profile WWW
April 28, 2014, 05:05:35 PM
 #53


but if it is a simulation as some said, what would be the real size of the "universal pixel"?

Planck Length?

https://localbitcoins.com/?ch=80k | BTC: 1LJvmd1iLi199eY7EVKtNQRW3LqZi8ZmmB
Spendulus
Legendary
*
Offline Offline

Activity: 2898
Merit: 1386



View Profile
April 28, 2014, 11:37:36 PM
 #54

The answer to the Fermi Paradox is that we're living in a computer simulation, obviously.  Smiley

http://www.simulation-argument.com/simulation.html

Indeed, we're alone in this simulation. Other solar systems and planets are just a technical trick of the program, designed to be just a red herring. They're projected far enough away from us so that the limits and borders of our world are somewhat believable for us.
Well, clearly, then the Earth could well be just 6000 years old.  Of course, I never understood how that theory jived with sedimentary rock, but hey, in a simulation, someone could be monkeying with the controls, you know, until one day, we find out and lay some traps for the bastard.  And let me tell you, he's gonna be in deep shit then.  

And maybe he didn't know what that even was, being off there in that realspace and we down here in simulcra.  

And that's the problem with that hypothesis, isn't it?  That elsewhere is the real.
Wilikon (OP)
Legendary
*
Offline Offline

Activity: 1176
Merit: 1001


minds.com/Wilikon


View Profile
April 29, 2014, 05:19:41 AM
 #55






Goldilocks zone

Perhaps the most habitable planet found to date is the recently announced Kepler-186f. This is one of five exoplanets discovered by NASA’s Kepler satellite, all orbiting a small, faint, red dwarf star, 500 light years away in the constellation of Cygnus.

Kepler-186f is an Earth-sized planet that orbits its star in only 130 days and is about as distant from its star as Mercury is from the Sun. But because the red dwarf is much dimmer than the Sun, Kepler-186f receives only about one-third of the energy that the Earth does. As a result, Kepler-186f lies at the outer edge of its star’s “habitable zone.” This is the hypothetical region of space surrounding a star in which liquid water may conceivably exist on the surface of any exoplanets.

In our own Solar System, Venus lies too close to the Sun and is too hot. Mars lies too far from the Sun and is too cold. But Earth, of course, lies within the critical “Goldilocks zone,” where the temperature is just right.

Simply residing in the habitable zone, though, is no guarantee that an exoplanet has water oceans. The climate of a planet is much more complicated than what we can capture with a simple calculation based on the distance of a planet from its star. We know that Mars probably had running water on its surface in the past, but now it is a frozen desert. Earth, meanwhile, was probably in a completely frozen “snowball” state about 650 million years ago.

Even leaving aside questions of climate, not all exoplanets have a surface on which liquid water could exist. Many of the exoplanets found in the past 20 years are massive, Jupiter-sized planets. This is not surprising, as bigger planets are easier to find (even if they are not the most numerous). But a Jupiter-sized exoplanet in the habitable zone of a star is unlikely to have liquid water, much less prove a suitable habitat for life as we know it. Jupiter has an outer atmosphere of gaseous and liquid hydrogen overlaying a metallic hydrogen envelope that extends for thousands of kilometers. Any rocky surface is confined to a core buried under millions of atmospheres of pressure.

But if a Jupiter-like exoplanet orbits within a star’s habitable zone, it begs the question: might that exoplanet host habitable moons like the Ewok’s home? Jupiter has Europa, which is suspected to have liquid water buried under an ice crust, and Saturn has Enceladus, which definitely has water hidden underneath its coat of ice. So Earth-like exomoons are certainly not out of the question.

http://arstechnica.com/science/2014/04/move-over-exoplanets-exomoons-may-harbor-life-too/

beetcoin
Sr. Member
****
Offline Offline

Activity: 434
Merit: 250


View Profile
April 29, 2014, 06:10:03 AM
Last edit: April 29, 2014, 06:25:53 AM by beetcoin
 #56

yeah i think most planets and intelligent life probably go through same cycle as we do.. and up killing themselves.

also, humans/intelligent life on earth have only existed for 200,000 years, while the planet's age is 5 billion years old. on a cosmic scale, that's the equivalent of.. 1/500th of the planet's history. of that 1/500th of earth's history, we have lived for 99.9% of it unable to send out signals for other intelligent life.
Pages: « 1 2 [3]  All
  Print  
 
Jump to:  

Powered by MySQL Powered by PHP Powered by SMF 1.1.19 | SMF © 2006-2009, Simple Machines Valid XHTML 1.0! Valid CSS!