Sorta debunks the whole thing, or at least makes life there appear pretty unlikely.
Possible new habitable planet - Page 4
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Hans-Titan
Denmark1711 Posts
Sorta debunks the whole thing, or at least makes life there appear pretty unlikely. | ||
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Myles
United States5162 Posts
On May 17 2010 20:33 LastWish wrote: I'm really confused by all of this theory of relativity... So let's say we've already habitated this distant planet. Now let's say we have a communication method which would also go 50% of lightspeed. So if I try to communicate with the distant planet It gets 40 years to send signal to the otherside and 40 years to return the answer. I'll be 80 years older. But.. if I travel by myself and return back I'll be only 68 years older? Could someone explain how and most importantly why it works as it does? When you communicate using any kind of wave(radio, xray, whatever) those waves move at the speed of light, and because they are effectively massless, do not experience the effects relativity. Thus, communication between Earth and a planet 20 light years away will always take 20 years to get there and 20 years to get back. People, or anything with mass, experience relativity as speed increases. So, if you're going 50% the speed of light and traveled for 40 years, you would only experience 34.6 years, while everyone around you moving at 'normal' speed would still experience the whole 40 years. | ||
LastWish
2013 Posts
On May 18 2010 01:30 Myles wrote: When you communicate using any kind of wave(radio, xray, whatever) those waves move at the speed of light, and because they are effectively massless, do not experience the effects relativity. Thus, communication between Earth and a planet 20 light years away will always take 20 years to get there and 20 years to get back. People, or anything with mass, experience relativity as speed increases. So, if you're going 50% the speed of light and traveled for 40 years, you would only experience 34.6 years, while everyone around you moving at 'normal' speed would still experience the whole 40 years. So if I go orbiting around the planet on a shuttle that travels like 90% of speed of light i'd experience 40*sqrt(1-(9/10c)^2/c^2) = aprox. 17.5 years. And when I return back everyone else has experienced 40 years, so I'd be 22.5 years younger than my previous peers? Could I make a presumption that when reaching speed of light(although it's said to be impossible) time freezes? | ||
love1another
United States1844 Posts
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Ganondorf
Italy600 Posts
http://planetquest.jpl.nasa.gov/TPF/tpf_index.cfm | ||
sgeng
United States78 Posts
On May 17 2010 14:36 endGame wrote: Would that really work? Afterall, 20 lightyears is pretty far away, do we have radio-telescopes powerful enough to pick up any radio waves from there? Actually I was surprised that we found one this close to us. 20 lightyears on the cosmic scale is pretty much equivalent to nearly nothing. The closest star to us is 4.5 lightyears away, so this one is only 5 times that distance. Granted it's still super super far if we actually wanna travel there though. | ||
Ganondorf
Italy600 Posts
On May 18 2010 02:26 sgeng wrote: Actually I was surprised that we found one this close to us. 20 lightyears on the cosmic scale is pretty much equivalent to nearly nothing. The closest star to us is 4.5 lightyears away, so this one is only 5 times that distance. Granted it's still super super far if we actually wanna travel there though. It's not too far if you want to accelerate a probe and shoot it there like a projectile (then somehow slow it down, maybe with a ion drive) at relativistic speeds, you could get a probe there in maybe 40 years travel time and get some images and data back in another 20 years, so that's "only" 60 years. Which is, cosmologically speaking, a really short time. | ||
Jayve
155 Posts
On May 17 2010 14:29 Grobyc wrote: I want to live to be old enough where we are able to "move" to this planet. Earth is getting pretty boring yo For some reason I pictured this old man coming out of a spaceship, landing on the planet and screaming: FIRST! :D | ||
shroomz
United Kingdom10 Posts
On May 18 2010 02:02 LastWish wrote: So if I go orbiting around the planet on a shuttle that travels like 90% of speed of light i'd experience 40*sqrt(1-(9/10c)^2/c^2) = aprox. 17.5 years. And when I return back everyone else has experienced 40 years, so I'd be 22.5 years younger than my previous peers? Could I make a presumption that when reaching speed of light(although it's said to be impossible) time freezes? That's correct on both counts, but the second is also wrong because you could never reach the speed of light since it by definition requires you to have no mass. | ||
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cgrinker
United States3824 Posts
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Aelfric
Turkey1496 Posts
http://www.hellofromearth.net/ | ||
Zurles
United Kingdom1659 Posts
On May 20 2010 07:34 Aelfric wrote: What? I know of Gliese 581c for something like 2 years, it is not something new. And it is not a good candidate for life supporting planet either, Gliese 581d is much better for this. Also there is a message collected and sent to Gliese581d you can see the progress here: http://www.hellofromearth.net/ They'll definitely speak English on Gliese 581d. | ||
Chupacabra(UCSD)
Mexico225 Posts
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EvilSky
Czech Republic548 Posts
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Aether
Canada123 Posts
On May 17 2010 14:32 Ciryandor wrote: One could try focusing radio-telescopes to listen if they've been using radio waves etc for communications. If they're at a similar stage to us x years before now, we could potentially listen in to them, all we'd need are "compatible receivers" ehhh, I think when they say they want to see if there is alien life, they probably don't mean they want to see if the planet is inhabited by humanoid creatures with technology, but rather are there things like bacteria and other primitive life forms living on the planet. | ||
Marradron
Netherlands1586 Posts
On May 17 2010 20:57 ~ava wrote: is this article old (from 2007)? The article says "of the 220 or so exoplanets found to date..." but Wikipedia says that as of 14-May-2010 we know of 454 extra solar planets. Finding planets in the galixy is actually not as simple as they make it seem. You can only investigate some kinds of radiation. Light is hardly ever used. Of all the light you see 99.99 procent is from the stars. Detecting a planed near a sun is like finding a green litle rock on a grass field the size of 10 foodball fields. Then you know there is something orbiting the star. And you still gotta filter out the contents of it. Basicly we've only found 454 things orbiting a star while we've already found thousands if not millions of stars / galaxys | ||
NiiPPLES
United Kingdom201 Posts
On May 17 2010 14:43 orgolove wrote: So if a kid is 10 years old, and boards a spaceship that can go 50% of lightspeed, even then he will become 50yo by the time he reaches that planet? :/ Fat chance any of us will make there during our lifetime. Ahah! But there's the great part, fifty years for him would be a couple hundred years for us! | ||
NeVeR
1352 Posts
On May 17 2010 21:27 Hans-Titan wrote: http://en.wikipedia.org/wiki/Gliese_581_c Sorta debunks the whole thing, or at least makes life there appear pretty unlikely. | ||
Darpa
Canada4413 Posts
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MidKnight
Lithuania884 Posts
On May 17 2010 15:25 JinMaikeul wrote: I always wonder... If there are actually aliens out there capable of travelling to this planet, is it really prudent to be throwing radio waves and other noise in their direction? While we would undoubtedly be fascinated by finding extraterrestrial life, what if finding alien species is nothing special to them and all we're doing with our radio waves is annoying them (sort've like a person constantly honking their horn annoys the crap out of the rest of us just sitting around trying to mind our own business). Does anyone else ever wonder if we may be irking potentially violent alien species to capable of interstellar travel to come and annihilate or enslave humanity? I will go ahead and assume if they're capable of travelling between the stars to reach us, we'd probably be completely screwed in any conflict from a technological standpoint... And it's not even like we'd be able to communicate with them right off the bat to explain to them why we're harassing them either. What are you talking about. We have siege tanks and vultures with mines. Those protoss have nothing on us But seriously sooner or later humanity will be able to get a confirmation about lifeforms outside of earth..I am hopeful that there aren't many people left thinking that we are the only ones in the universe big as it is.. I wonder how would religious folks react if it was confirmed that some form of life on other planets (even something as primitive as bacteria). Would that be sufficient to make them stfu finally? | ||
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