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Science Section => Science General Discussion => Topic started by: MyelinSheath on May 04, 2017, 01:59:17 AM

Title: Exoplanets
Post by: MyelinSheath on May 04, 2017, 01:59:17 AM
Just found out that we have only known about the existence of exoplanets since 1992. This is hard to believe. I figured we had made this discovery at least a century ago. I mean, I was born in 1991. I remember assuming that there were millions of galaxies and millions of stars all with planets orbiting them since I was a little bitty boy. I figured the knowledge of this came way before I was born. What the hell humans? This changes so much. I'm depressed now.
Title: Re: Exoplanets
Post by: Baruch on May 04, 2017, 07:24:43 AM
Rapid change is stressful .. but exciting.  Some science isn't boring today, it has rapid discoveries.  Other science, not so much.  And yes, people did exist before you were born ... even my daughter, who is one year older than you ;-)
Title: Re: Exoplanets
Post by: Hydra009 on May 04, 2017, 05:32:34 PM
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Just found out that we have only known about the existence of exoplanets since 1992. This is hard to believe. I figured we had made this discovery at least a century ago.
The first confirmed detection was in 1992.  Astronomers had a pretty solid inkling that they were there long before that.

Since technology has advanced to the point of allowing astronomers to prove their suspicions, astronomers have found a ton of them.  And just recently, they're also detected an atmosphere around an Earth-like planet (https://www.sciencedaily.com/releases/2017/04/170406152402.htm).  Very exciting.
Title: Re: Exoplanets
Post by: SGOS on May 05, 2017, 05:30:01 AM
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Just found out that we have only known about the existence of exoplanets since 1992. This is hard to believe. I figured we had made this discovery at least a century ago. I mean, I was born in 1991. I remember assuming that there were millions of galaxies and millions of stars all with planets orbiting them since I was a little bitty boy. I figured the knowledge of this came way before I was born. What the hell humans? This changes so much. I'm depressed now.
How about plate tectonics?  In grade school, I was presented with the notion, but it was like the astronomers suspicions of exoplanets and much in debate, with some authorities laughing at the idea.  My grade school teacher showed how the shorelines of Europe and Africa kind of fit into North and South America, because she was pointing out both sides of a heated debate, not because she actually believed it.  Of course, the coincidence of shorelines that jig sawed together by itself, was a pretty lame bit of evidence.  I think my teacher kind of played that up, and correctly pointed out that the fit could have been purely coincidence, and it could have been until scientists started finding otherwise unexplainable geological and biological matches between what should have been isolated landforms.  Twenty years later, what we had laughed at in elementary school had been confirmed, and even measured.

Like your perception of exoplanets, it strikes me as strange that such a well understood geological event as tectonics is only a recent discovery.  It's even stranger that during my own lifetime, it had been at one time little more than the suspicions of outcasts in the scientific community.  For those who can tolerate change, we live in exciting times as advances in our knowledge base are happening more and more rapidly.  In the last 30 days, Scientific knowledge has probably seen greater changes than the first hundred thousand years of mankind's existence, and I'm quite certain that it's more than what we experienced between the fall of Rome to the Renaissance.
Title: Re: Exoplanets
Post by: Mike Cl on May 05, 2017, 09:43:32 AM
When I was in school, I was taught that photosynthesis was the basis for all life on Earth.  That has been shown to be not so, with the teeming life sustained by ocean bottom smokers.  That has been a fairly recent discovery as well.  There must be more examples of that. 

I have always marveled at the discoveries my grandfather lived through.  When he was born, he knew nothing of automobiles, airplaines, TV, computers,--a bunch of stuff.  His 1880's world was a much different place than the world he knew when he passed in the 70's.  But don't we all go through a similar experience?   
Title: Re: Exoplanets
Post by: Gawdzilla Sama on May 06, 2017, 06:40:43 AM
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Just found out that we have only known about the existence of exoplanets since 1992. This is hard to believe. I figured we had made this discovery at least a century ago. I mean, I was born in 1991. I remember assuming that there were millions of galaxies and millions of stars all with planets orbiting them since I was a little bitty boy. I figured the knowledge of this came way before I was born. What the hell humans? This changes so much. I'm depressed now.
Confirmed in 1992. Tyson says it's like detecting a moth flying in front of a searchlight in Los Angeles from your observation point in New York.
Title: Re: Exoplanets
Post by: Unbeliever on May 08, 2017, 08:02:45 PM
At least one star has 7 earthlike plantes:

NASA Telescope Reveals Largest Batch of Earth-Size, Habitable-Zone Planets Around Single Star (https://www.nasa.gov/press-release/nasa-telescope-reveals-largest-batch-of-earth-size-habitable-zone-planets-around)


Quote
NASA's Spitzer Space Telescope has revealed the first known system of seven Earth-size planets around a single star. Three of these planets are firmly located in the habitable zone, the area around the parent star where a rocky planet is most likely to have liquid water.



(https://d3i6fh83elv35t.cloudfront.net/newshour/wp-content/uploads/2017/02/image2_PIA21422-1024x512.jpg)



But the term "earthlike" is a technical term that doesn't really imply a truly earthlike planet. Just a relatively small, rocky orb - even the moon would be considered "earthlike" by their standards.
Title: Re: Exoplanets
Post by: Munch on May 27, 2017, 07:49:40 PM
Somethings I wonder if the oxygen on our planet is the only one of that kind, it being how life adapted to it, but its also why we're never find another planet with our atmosphere. Not to say other forms of life didn't adapt to its enviroment, but since all life here formed from single celled organisms adaping to the environment already here, I doubt we're ever find another planet we're just be able to land and breath on if we could get there.
Title: Re: Exoplanets
Post by: aitm on May 27, 2017, 09:24:06 PM
3 thousand years ago, and prior of course, they thought rain fell from the sky because the sky was water...hence genesis 1.
Title: Re: Exoplanets
Post by: Baruch on May 27, 2017, 10:28:35 PM
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3 thousand years ago, and prior of course, they thought rain fell from the sky because the sky was water...hence genesis 1.

And in the future, we will all be demigods of mad science.  Already beat you there ;-)
Title: Re: Exoplanets
Post by: trdsf on June 02, 2017, 10:34:34 AM
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Somethings I wonder if the oxygen on our planet is the only one of that kind, it being how life adapted to it, but its also why we're never find another planet with our atmosphere. Not to say other forms of life didn't adapt to its enviroment, but since all life here formed from single celled organisms adaping to the environment already here, I doubt we're ever find another planet we're just be able to land and breath on if we could get there.
There are two important things about an oxygen atmosphere.  The first is that it permits really active organisms like us to evolve.  Doesn't mean they will, of course, but it opens that door.

And the second is that an oxygen atmosphere is unstable without something at the base of it like plants and algae continually replenishing the oxygen supply.  So when we get to the point that we can do spectrographic analysis of an exoplanet, then if we spot oxygen, we have almost certainly spotted a planet that has simple life at least.

And if we spot the kind of crud that we have put into our own atmosphere, that's indicative of technology and therefore of intelligent life.

Now, assuming we could reach an exoplanet with an oxygen atmosphere, it's going to depend.  If there's nothing genuinely toxic like hydrogen cyanide or the like and the O2 content isn't too far off our 20% or so and the other 80% is largely inert (N2 and/or noble gases like neon, argon and krypton) and the pressure isn't too high or too low, there's no reason it wouldn't be breathable.

But I would like at least a filter until we understood that world's biology better.  I've seen how War of the Worlds ends.
Title: Re: Exoplanets
Post by: Baruch on June 02, 2017, 01:13:46 PM
Life seems to require consumption of energy, usually chemical ... burning involves oxygen mostly, but also apparently hydrogen sulfide.  So the chemical possibilities are limited to certain elements, simple molecules .. for the energy process ... exothermic.  Now plants are pretty endothermic ... but even they have sugars, which are burned in cellular processes (see sugar cane).  I am not sure that animal life is even possible, except by parasitism by them over plants, who are good at storing solar energy, which can then be robbed.
Title: Re: Exoplanets
Post by: Unbeliever on June 02, 2017, 05:18:17 PM
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And the second is that an oxygen atmosphere is unstable without something at the base of it like plants and algae continually replenishing the oxygen supply.  So when we get to the point that we can do spectrographic analysis of an exoplanet, then if we spot oxygen, we have almost certainly spotted a planet that has simple life at least.

Yeah, this was James Lovelock's (http://www.jameslovelock.org/) brilliant idea. We'll soon be able to do this - in fact, probably can now, to some extent.
Title: Re: Exoplanets
Post by: Baruch on June 03, 2017, 05:01:33 PM
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Yeah, this was James Lovelock's (http://www.jameslovelock.org/) brilliant idea. We'll soon be able to do this - in fact, probably can now, to some extent.

Earth has simple life ... humans ;-)
Title: Re: Exoplanets
Post by: trdsf on June 06, 2017, 03:48:43 PM
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Yeah, this was James Lovelock's (http://www.jameslovelock.org/) brilliant idea. We'll soon be able to do this - in fact, probably can now, to some extent.
Indeed we can (http://www.space.com/36368-atmosphere-found-on-nearly-earth-size-planet.html).  I think the only ones we can currently get are the ones that transit, and many of those are so close in they can't really be considered potential habitats, but this is a new field and every piece of data is an interesting piece of data.
Title: Re: Exoplanets
Post by: Unbeliever on June 06, 2017, 05:05:45 PM
Good link, thanks!

They found a star called Trappist-1 (https://www.nasa.gov/press-release/nasa-telescope-reveals-largest-batch-of-earth-size-habitable-zone-planets-around) that has as many as 7 "Earthlike" planets, any or all of which could have liquid water. This is a good time to be an astronomer!
Title: Re: Exoplanets
Post by: Baruch on June 06, 2017, 07:50:26 PM
You will find that any Goldilocks planet is already claimed by the bear tribe ;-)
Title: Re: Exoplanets
Post by: Unbeliever on June 07, 2017, 05:02:29 PM
I'm not so sure anymore that there is such a thing as a Goldilocks planet. Liquid water apparently can exist in many more contexts than was previously thought, and life can exist in many more places than previously thought.

It's not like humanity will ever find any other planet we'll be able to live on. I think that, to some extent, sci-fi authors have done the world a disservice - they've made too many people believe that finding another home for humanity is a fairly simple matter, so we can trash the Earth and just go find another one out there somewhere.
Title: Re: Exoplanets
Post by: Baruch on June 07, 2017, 08:42:29 PM
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I'm not so sure anymore that there is such a thing as a Goldilocks planet. Liquid water apparently can exist in many more contexts than was previously thought, and life can exist in many more places than previously thought.

It's not like humanity will ever find any other planet we'll be able to live on. I think that, to some extent, sci-fi authors have done the world a disservice - they've made too many people believe that finding another home for humanity is a fairly simple matter, so we can trash the Earth and just go find another one out there somewhere.

Yes, and all alien races, thanks to our radio and TV transmissions, already speak American (not British) English ;-)
Title: Re: Exoplanets
Post by: trdsf on June 08, 2017, 11:27:06 AM
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I'm not so sure anymore that there is such a thing as a Goldilocks planet. Liquid water apparently can exist in many more contexts than was previously thought, and life can exist in many more places than previously thought.

It's not like humanity will ever find any other planet we'll be able to live on. I think that, to some extent, sci-fi authors have done the world a disservice - they've made too many people believe that finding another home for humanity is a fairly simple matter, so we can trash the Earth and just go find another one out there somewhere.
And that's what happens when you write speculative fiction in the absence of hard data.  Until only about 25 years ago, extrasolar planets were strictly theoretical, and it was broadly assumed that if we started finding other systems, they would be generally similar to ours: orderly, with the rocky Earth-likes close in and the gas giants far out.  Which, using the principle of mediocrity (https://en.wikipedia.org/wiki/Mediocrity_principle), wasn't an unreasonable assumption to make.  Now we know that planets are in all sorts of weird orbits, around all sorts of stars, but that's not the fault of the SF writers.  And some of them did assume terraforming marginally habitable worlds (and even uninhabitable ones), or a ubiquity of intelligences on worlds utterly hostile to Terrestrial life.

If there's a problem with public expectations derived from fictional worlds, it's with those who assume that fiction necessarily maps reality, and with an education system that relies on cramming data rather than critical thinking.  It's not with the creators of the fiction.

As far as defining Goldilocks zones, I think we need to start talking about that in terms of different degrees of 'just right', and without sharp lines between them.  So a Class I Goldilocks zone is suitable to the development of microbial and extremely simple multicellular life, but unlikely to be able to support anything more complex.  A Class II zone might support plants and simple animals, but lack anything that pushes evolution forward -- a good environment, but too stable.  And a Class III zone is stable over the long term but variable within limits over the short term, permitting complex life to arise and challenging enough that natural evolution continues to progress rather than finds a stopping point.  Or something like that.
Title: Re: Exoplanets
Post by: Unbeliever on June 09, 2017, 05:46:43 PM
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Yes, and all alien races, thanks to our radio and TV transmissions, already speak American (not British) English ;-)
Only the ones that are within about 70 or so light years. Farther than that and they can't yet know about us at all. They may, though, be aware that there's life of a simple kind here. They just don't know about our civilization, as yet.
Title: Re: Exoplanets
Post by: trdsf on June 10, 2017, 10:29:57 PM
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Only the ones that are within about 70 or so light years. Farther than that and they can't yet know about us at all. They may, though, be aware that there's life of a simple kind here. They just don't know about our civilization, as yet.
Actually, if they have sufficient technology to detect our planet in the same way that we spot exoplanets, and if they are capable of resolving Earth independently so they can do a spectrographic analysis of our atmosphere, we're potentially detectable out to nearly 200 light years from the gunk we were putting into the air.
Title: Re: Exoplanets
Post by: Cavebear on July 11, 2017, 08:44:56 AM
And, interestingly, I have read that our radio and TV signals are essentially static a few light year out.  It might be that no signals of intelligence travel very far in any detectable way. 
Title: Re: Exoplanets
Post by: trdsf on July 12, 2017, 06:54:14 AM
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And, interestingly, I have read that our radio and TV signals are essentially static a few light year out.  It might be that no signals of intelligence travel very far in any detectable way.
True.  Our radio and television signals would be very difficult to pick up even as near as Proxima Centauri, and virtually impossible to pick up any further out, because signal attenuation follows an inverse square law - twice the distance, 1/4th the signal, ten times the distance, 1/100th the signal.  The best way to identify other ETIs is probably going to be identifying planets (or large moons) within a star's habzone and doing spectrographic analysis, looking for oxygen or acetylene  or other gases that probably require a biological presence to explain -- or, ironically the best sign of all, atmospheric pollutants -- and then bearing all appropriate resources down on that world, sending relativistic probes and listening very closely in case they're broadcasting to be heard.
Title: Re: Exoplanets
Post by: Unbeliever on July 12, 2017, 02:49:00 PM
It's likely that any intelligent species out there will have evolved from a predatory species, just because it takes more brains to hunt and kill prey than to simply munch leaves and hide. So we should hope they don't know about us!
Title: Re: Exoplanets
Post by: trdsf on July 12, 2017, 03:43:17 PM
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It's likely that any intelligent species out there will have evolved from a predatory species, just because it takes more brains to hunt and kill prey than to simply munch leaves and hide. So we should hope they don't know about us!
That's a point mentioned by Helen Keen in her BBC Radio 4 series, It Is Rocket Science (http://www.helenkeen.com/rocket.html), and a good one.  The only reasonably good refutation of it is to consider the possibility that that's the course evolution took here, but that intelligence and predatory behavior are not necessarily inextricably linked.  Sufficiently nutritious vegetation (or its equivalent), for example, can provide the necessary energy for a large brain as well as meat did for us.

Of course, another good reason to keep our collective heads down is because if you want to know what encountering a more technologically advanced civilization is like, you can ask the (remaining) indigenous people of North and South America and Australia.
Title: Re: Exoplanets
Post by: Unbeliever on July 12, 2017, 03:47:58 PM
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Sufficiently nutritious vegetation (or its equivalent), for example, can provide the necessary energy for a large brain as well as meat did for us.
Maybe, but I think nutritious plants wouldn't provide enough of a challenge to make intelligence useful, much less necessary.

Title: Re: Exoplanets
Post by: Baruch on July 12, 2017, 06:49:02 PM
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It's likely that any intelligent species out there will have evolved from a predatory species, just because it takes more brains to hunt and kill prey than to simply munch leaves and hide. So we should hope they don't know about us!

That is exactly why the Elite are the master-class, if not the master-race.
Title: Re: Exoplanets
Post by: trdsf on July 13, 2017, 12:46:47 PM
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Maybe, but I think nutritious plants wouldn't provide enough of a challenge to make intelligence useful, much less necessary.
Hadn't thought of that, good point.

I mean, I expect that land based hunter-gatherer omnivores are the most promising basis on which to evolve an intelligent species.  I would like to come up with a reasonable way to get herbivores to sentience, just to build the case for them.  I think a carnivorous or omnivorous aquatic species would have a better chance at sentience, though -- you can get to a primitive mechanical society without fire, but of course that's going to be limited without an ability to extract ores.
Title: Re: Exoplanets
Post by: Baruch on July 13, 2017, 12:57:56 PM
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Hadn't thought of that, good point.

I mean, I expect that land based hunter-gatherer omnivores are the most promising basis on which to evolve an intelligent species.  I would like to come up with a reasonable way to get herbivores to sentience, just to build the case for them.  I think a carnivorous or omnivorous aquatic species would have a better chance at sentience, though -- you can get to a primitive mechanical society without fire, but of course that's going to be limited without an ability to extract ores.

Humans aren't the Federation, we are the pre-breakout Borg.
Title: Re: Exoplanets
Post by: Cavebear on July 14, 2017, 06:02:32 AM
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Maybe, but I think nutritious plants wouldn't provide enough of a challenge to make intelligence useful, much less necessary.

I agree completely.  Even very nutritious plant food doesn't require intelligence to eat.  Although if the plants could run, it might.  Intelligence comes from outsmarting something.  Grass-eaters just have to be smarter than grass and aware enough to run from meat-eaters. 

And then the question is "How much smarter are we than our food compared the the top predators on another planet"?  Would you like to meet a lion smarter and more technologically-able than you?
Title: Re: Exoplanets
Post by: Atheon on July 14, 2017, 09:29:26 AM
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Just found out that we have only known about the existence of exoplanets since 1992. This is hard to believe. I figured we had made this discovery at least a century ago. I mean, I was born in 1991. I remember assuming that there were millions of galaxies and millions of stars all with planets orbiting them since I was a little bitty boy. I figured the knowledge of this came way before I was born. What the hell humans? This changes so much. I'm depressed now.
1992 was the first confirmed detection of an exoplanet.

As a kid I read about the transit method as a possible means of detecting exoplanets. This was in 1977 or 1978.

Scientists had theorized the almost certain existence of planets around other stars for many decades before 1992, and this was fodder for science fiction stories like Buck Rogers, Star Trek, Star Wars and so forth.
Title: Re: Exoplanets
Post by: trdsf on July 14, 2017, 01:10:16 PM
And assuming other planets is a simple application of the principle of mediocrity, that we should not assume there's anything peculiar about our immediate environment just because we're in it.  To assume that out of the hundreds of billions of stars just in our own galaxy the only planet was this one was absurd statistically as well as an appalling display of hubris.

Ironically, it was an assumption based on our solar system that kept Butler and Marcy from making the first exoplanet discovery around a main sequence star: they were looking for nice neat nearly-circular ellipses and an orderly set of orbits at "sensible" differences.  Mayor and Quiroz were willing to look at any sort of orbit, and they got the prize; Butler and Marcy in fact had data on 51 Pegasi and were able to confirm their rivals' discovery within a week, and everyone was shocked that a Jupiter-class planet could orbit its star in just 4 days in just an eccentric orbit.

This, by the bye, is one of the things I love about science, because certainly Butler and Marcy had every reason to hope the finding was in error so they could be first.  But that's not what the data said, and the data is the only thing that counts, and so they ended up providing the essential confirmation of the discovery that they didn't get to make.

FWIW, the first exoplanet discovered was in 1989, but it wasn't confirmed as a planet until 2012.  It was originally thought to be a brown dwarf.  Its existence was confirmed in 1991, but its status as a sub-stellar object wasn't settled until 21 years later.
Title: Re: Exoplanets
Post by: Cavebear on July 14, 2017, 01:46:17 PM
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And assuming other planets is a simple application of the principle of mediocrity, that we should not assume there's anything peculiar about our immediate environment just because we're in it.  To assume that out of the hundreds of billions of stars just in our own galaxy the only planet was this one was absurd statistically as well as an appalling display of hubris.

Ironically, it was an assumption based on our solar system that kept Butler and Marcy from making the first exoplanet discovery around a main sequence star: they were looking for nice neat nearly-circular ellipses and an orderly set of orbits at "sensible" differences.  Mayor and Quiroz were willing to look at any sort of orbit, and they got the prize; Butler and Marcy in fact had data on 51 Pegasi and were able to confirm their rivals' discovery within a week, and everyone was shocked that a Jupiter-class planet could orbit its star in just 4 days in just an eccentric orbit.

This, by the bye, is one of the things I love about science, because certainly Butler and Marcy had every reason to hope the finding was in error so they could be first.  But that's not what the data said, and the data is the only thing that counts, and so they ended up providing the essential confirmation of the discovery that they didn't get to make.

FWIW, the first exoplanet discovered was in 1989, but it wasn't confirmed as a planet until 2012.  It was originally thought to be a brown dwarf.  Its existence was confirmed in 1991, but its status as a sub-stellar object wasn't settled until 21 years later.

Still, uniqueness is possible.  At one time, there was only one human on antactica (someone had to step on the ice first).  and later a one person to step on the moon.  Oners are always possible and in those situations, nearly required. 

We could be the first, only, or last to get from one star to another.  And it is worth considering that humans are the only creatures on Earth who CAN say "You bother me enough, I will exterminate you!

Here, anyway, and at a macro level...  But I still worry about the Voyager spacecrafts as a "scent trail"...  We might be the most lethal species on the planet, but what about meaner planets?

OK, sure, maybe interstellar travel requires a kinder more mature species.  But the Atlantic Ocean was once consider uncrossable.  Ask the Incans how THAT worked out...
Title: Re: Exoplanets
Post by: trdsf on July 14, 2017, 03:27:56 PM
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Still, uniqueness is possible.  At one time, there was only one human on antactica (someone had to step on the ice first).  and later a one person to step on the moon.  Oners are always possible and in those situations, nearly required.
Oh absolutely it's possible.  I don't think it's probable until more data comes in, and it's going to be difficult data to obtain.  And even a null result from listening only tells us there are no communicating intelligences out there.

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We could be the first, only, or last to get from one star to another.  And it is worth considering that humans are the only creatures on Earth who CAN say "You bother me enough, I will exterminate you!
And entirely capable of being the Daleks of this galaxy, given enough time.

One of the few writers to posit a humans-only galaxy was Asimov, who resorted to it because his editor John Campbell insisted essentially that aliens always be inferior to humans, and Asimov did not care for that limitation.

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Here, anyway, and at a macro level...  But I still worry about the Voyager spacecrafts as a "scent trail"...  We might be the most lethal species on the planet, but what about meaner planets?
I'm not sure that the map on the Voyager disk is all that clear.  It's not really obvious that the binary is meant to represent several pulsars from which our position can be triangulated.  And even if someone does find it, and does sort out the meanings on the Golden Record, coming here would -- assuming there's no shortcut around Einstein that they've figured out and we haven't -- remain a daunting prospect.  And would be tens of thousands of years in the future anyway, as it's going to be that long before either of the Voyagers pass near any star, and the first ones they approach aren't good candidates for intelligent life.

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OK, sure, maybe interstellar travel requires a kinder more mature species.  But the Atlantic Ocean was once consider uncrossable.  Ask the Incans how THAT worked out...
Yup.
Title: Re: Exoplanets
Post by: Cavebear on July 14, 2017, 04:36:21 PM
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Oh absolutely it's possible.  I don't think it's probable until more data comes in, and it's going to be difficult data to obtain.  And even a null result from listening only tells us there are no communicating intelligences out there.
And entirely capable of being the Daleks of this galaxy, given enough time.

One of the few writers to posit a humans-only galaxy was Asimov, who resorted to it because his editor John Campbell insisted essentially that aliens always be inferior to humans, and Asimov did not care for that limitation.
I'm not sure that the map on the Voyager disk is all that clear.  It's not really obvious that the binary is meant to represent several pulsars from which our position can be triangulated.  And even if someone does find it, and does sort out the meanings on the Golden Record, coming here would -- assuming there's no shortcut around Einstein that they've figured out and we haven't -- remain a daunting prospect.  And would be tens of thousands of years in the future anyway, as it's going to be that long before either of the Voyagers pass near any star, and the first ones they approach aren't good candidates for intelligent life.
Yup.

If alien travelers just passing by, not considering Sol worth checking, came across the Voyagers, they could easily track the paths back to us.  And if they travelling, we're toast.

Maybe they would be nice.  That plot doesn't usually work out too well. 

In fact, I can't think of a plot that works out well for us unless we are first.  And I don't even like THAT one.