View Full Version : First Earthlike Exoplanet Found
Exciting times! I'm tingling! A stable world in the goldilocks zone, and it's orbiting a very stable star, which means life has had many, many chances to evolve. Do you realize that this means we may find out about extrasolar life within the next fifty years? This is major. This is huge. (http://www.dailymail.co.uk/pages/live/articles/technology/technology.html?in_article_id=450467&in_page_id=1965)
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Found: The New Earth
By MICHAEL HANLON - Last updated at 22:33pm on 24th April 2007
It's got the same climate as Earth, plus water and gravity. A newly discovered planet is the most stunning evidence that life - just like us - might be out there.
Above a calm, dark ocean, a huge, bloated red sun rises in the sky - a full ten times the size of our Sun as seen from Earth. Small waves lap at a sandy shore and on the beach, something stirs...
This is the scene - or may be the scene - on what is possibly the most extraordinary world to have been discovered by astronomers: the first truly Earth-like planet to have been found outside our Solar System.
The discovery was announced today by a team of European astronomers, using a telescope in La Silla in the Chilean Andes.
The Earth-like planet that could be covered in oceans and may support life is 20.5 light years away, and has the right temperature to allow liquid water on its surface.
This remarkable discovery appears to confirm the suspicions of most astronomers that the universe is swarming with Earth-like worlds.
We don't yet know much about this planet, but scientists believe that it may be the best candidate so far for supporting extraterrestrial life.
The new planet, which orbits a small, red star called Gliese 581, is about one-and-a-half times the diameter of the Earth.
It probably has a substantial atmosphere and may be covered with large amounts of water - necessary for life to evolve - and, most importantly, temperatures are very similar to those on our world.
It is the first exoplanet (a planet orbiting a star other than our own Sun) that is anything like our Earth.
Of the 220 or so exoplanets found to date, most have either been too big, made of gas rather than solid material, far too hot, or far too cold for life to survive.
"On the treasure map of the Universe, one would be tempted to mark this planet with an X," says Xavier Delfosse, one of the scientists who discovered the planet.
"Because of its temperature and relative proximity, this planet will most probably be a very important target of the future space missions dedicated to the search for extraterrestrial life."
Gliese 581 is among the closest stars to us, just 20.5 light years away (about 120 trillion miles) in the constellation Libra. It is so dim it can be seen only with a good telescope.
Because all planets are relatively so small and the light they give off so faint compared to their sun, finding exoplanets is extremely difficult unless they are huge.
Those that have so far been detected have mostly been massive, Jupiter-like balls of gas that almost certainly cannot be home to life.
This new planet - known for the time being as Gliese 581c - is a midget in comparison, being about 12,000 miles across (Earth is a little under 8,000 pole-to-pole).
It has a mass five times that of Earth, probably made of the same sort of rock as makes up our world and with enough gravity to hold a substantial atmosphere.
Astrobiologists - scientists who study the possibility of alien life - refer to a climate known as the Goldilocks Zone, where it is not so cold that water freezes and not so hot that it boils, but where it can lie on the planet's surface as a liquid.
In our solar system, only one planet - Earth -lies in the Goldilocks Zone. Venus is far too hot and Mars is just too cold. This new planet lies bang in the middle of the zone, with average surface temperatures estimated to be between zero and 40c (32-102f). Lakes, rivers and even oceans are possible.
It is not clear what this planet is made of. If it is rock, like the Earth, then its surface may be land, or a combination of land and ocean.
Another possibility is that Gliese 581c was formed mostly from ice far from the star (ice is a very common substance in the Universe), and moved to the close orbit it inhabits today.
In which case its entire surface will have melted to form a giant, planet-wide ocean with no land, save perhaps a few rocky islands or icebergs.
The surface gravity is probably around twice that of the Earth and the atmosphere could be similar to ours.
Although the new planet is in itself very Earth-like, its solar system is about as alien as could be imagined. The star at the centre - Gliese 581 - is small and dim, only about a third the size of our Sun and about 50 times cooler.
The two other planets are huge, Neptune-sized worlds called Gliese 581b and d (there is no "a", to avoid confusion with the star itself).
The Earth-like planet orbits its sun at a distance of only six million miles or so (our Sun is 93 million miles away), travelling so fast that its "year" only lasts 13 of our days.
The parent star would dominate the view from the surface - a huge red ball of fire that must be a spectacular sight.
It is difficult to speculate what - if any - life there is on the planet. If there is life there it would have to cope with the higher gravity and solar radiation from its sun.
Just because Gliese 581c is habitable does not mean that it is inhabited, but we do know its sun is an ancient star - in fact, it is one of the oldest stars in the galaxy, and extremely stable. If there is life, it has had many billions of years to evolve.
This makes this planet a prime target in the search for life. According to Seth Shostak, of the Search for Extraterrestrial Intelligence Institute in California, the Gliese system is now a prime target for a radio search. 'We had actually looked at this system before but only for a few minutes. We heard nothing, but now we must look again.'
By 2020 at least one space telescope should be in orbit, with the capability of detecting signs of life on planets orbiting nearby stars. If oxygen or methane (tell-tale biological gases) are found in Gliese 581c's atmosphere, this would be good circumstantial evidence for life.
Dr Malcolm Fridlund, a European Space Agency scientist, said the discovery of Gliese 581c was "an important step" on the road to finding life.
"If this is a rocky planet, it's very likely it will have liquid water on its surface, which means there may also be life."
The real importance is not so much the discovery of this planet itself, but the fact that it shows that Earth-like planets are probably extremely common in the Universe.
There are 200 billion stars in our galaxy alone and many astronomers believe most of these stars have planets.
The fact that almost as soon as we have built a telescope capable of detecting small, earth-like worlds, one turns up right on our cosmic doorstep, shows that statistically, there are probably billions of earths out there.
As Seth Shostak says: "We've never found one close to being like the Earth until now. We are finding that Earth is not such an unusual puppy in the litter of planets."
But are these alien Earths home to life? No one knows. We don't understand how life began on our world, let alone how it could arise anywhere else. There may be an awful lot of bugs and bacteria out there, and only a few worlds with what we would recognise as plants and animals. Or, of course, there may be nothing.
The Search for Extraterrestrial Intelligence Institute uses radio telescopes to try to pick up messages sent by alien civilisations.
Interestingly, Gliese 581c is so close to the Earth that if its putative inhabitants only had our level of technology, they could - just about - pick up some of our radio signals, such as the most powerful military transmitters. Quite what would happen if we for our part did receive a signal is unclear.
"There is a protocol, buried away in the United Nations," says Dr Shostak. "The President would be told first, after the signal was confirmed by other observatories. But we couldn't keep such a discovery secret."
It may be some time before we detect any such signals, but it is just possible that today we are closer than ever to finding life in the stars.
Sasaki Kojiro
04-25-2007, 01:46
And it's really close by too.
Atleast we now might have another planet to inhabit when we destroy this one.:sweatdrop:
discovery1
04-25-2007, 01:51
Incredible. Better try harder at this diffy Q homework then.
Crazed Rabbit
04-25-2007, 01:52
Very exciting indeed.
We can really only wonder if there's life on the planet...
CR
We can really only wonder if there's life on the planet...
We can do better that that; we can find out. Unleash our horde of robot drones!
Crazed Rabbit
04-25-2007, 01:59
Hey, we don't all have hordes of robot drones. Some of us put our resources into training an underground nation of rabbits to dominate the world.
Seriously, 20 light years is to far away for our lifetime.
CR
Strike For The South
04-25-2007, 02:07
I don't think I'm alone when I say I'd like to see more and more planets fall under the ruthless domination of our solar system.
Adrian II
04-25-2007, 02:19
We can do better that that; we can find out. Unleash our horde of robot drones!I'm reprogramming my sommelier robot as we speak! :laugh4: Exciting news indeed, Lemur.
CountArach
04-25-2007, 02:22
I for one support our new Robot Drone overlords. May their reign of terror be long.
Hosakawa Tito
04-25-2007, 02:31
Getting humans there is going to be a problem, we don't travel well at those distances. It's nice to dream though.
Begin building the Org's generation ship. (http://en.wikipedia.org/wiki/Generation_ship)
KafirChobee
04-25-2007, 02:38
Hadn't heard of this, so thx Lemus. Amazing stuff.
TevashSzat
04-25-2007, 02:49
The seasons would be a bit hectic there though, you'd go through a season in about just a day
And it'll only take us several thousand years to get there. Quick, stock up on clones and babies for the mothership!
Pannonian
04-25-2007, 02:57
We can do better that that; we can find out. Unleash our horde of robot drones!
Are these the robotic lemurs you had stashed away, along with Kommodus' nano-bots?
Sasaki Kojiro
04-25-2007, 03:01
And it'll only take us several thousand years to get there. Quick, stock up on clones and babies for the mothership!
Just install a "light speed" button.
Crazed Rabbit
04-25-2007, 03:08
The ambassador for the rabbit people would like to note that a rabbit requires much less sustenance than a man, and more rabbits could be supported in a ship for the resources it would take to support humans.
Also, we have an almost ready giant laser on the moon and we'll blast anyone who tries to get there before us.
CR
Well it would be cool if we could reach it sometime in the next 80 years so I would be able to know for sure. But after I discussed it with my science teacher he said that sure, there probably is, has been or will be intelligent life like ours somewhere in the universe. But the chances of them being at the same evolutionary stage as us and of all the planets in the universe us actually choosing the right one, doesn't make for very good odds.
So who knows, maybe they are still single celled life forms on that planet and it won't be another million years or so before they reach the stone age, or maybe they had a massive nuclear war or a plague and have all died out. Or that could just be the wrong planet.
It'd be cool if it could happen but I don't think any of us will live long enough to see any contact with aliens :sorry2:
Cool find Lemur:2thumbsup:
Don Corleone
04-25-2007, 03:47
That is really neat, but being 13 times closer to it's radiatant star is bound to make for some radioactive environments. Not to mention, if there is sentient life there, evolving under 2g means they could kick our ass!
Great find, I needed some good news to drown out the bad in the world. I'm all for the generation ship, drones as well. We need to bombard those Gliesians with radios, lights, and drones right away so when we eventually meet we can win the we saw you first argument. Now if only we could reach anywhere near the speed of light...
Heck if we send a ship now, by the time it reaches there I wouldn't doubt our having technology that could get there in a single lifetime. Our future spaceclowns will probably think the inbred offspring on the generation ship as the victims of a bunch of suckers as they whizz by us, probably mooning us as well.
Gregoshi
04-25-2007, 04:55
I was skeptical of the article at first because it seemed to be lacking the usual stuff you see in scientific articles - discovering scientists and their universities for example. Then there was nothing about this at my usual astronomy websites, nor at the SETI webpage - and one of their scientists is quoted in the article. Even a Google search yielded little. I did find a similar article at space.com though, so I'm happy it is true. :2thumbsup:
As for the travel time to the new planet, I think we should fire off a shipment of Twinkies right away as a peace offering to whoever or whatever is there. At least they will be fresh no matter how long the journey takes. Knowing our luck though, when we get there, the planet will be inhabited by giant mutant sentient Twinkies bent on revenge.
Joking aside, if we manage to even detect circumstantial evidence of life, it could spur interest and money to begin serious development of interstellar vehicles.
Samurai Waki
04-25-2007, 06:56
There is no possible way humans could ever travel at light speed. But if we ever figured out how exactley we could move space around the ship at light speeds it would be a completely different story... ahh. Science Fiction. The Fiction Part Worries me though.
doc_bean
04-25-2007, 09:23
That is really neat, but being 13 times closer to it's radiatant star is bound to make for some radioactive environments. Not to mention, if there is sentient life there, evolving under 2g means they could kick our ass!
It would depend on the radiation the star sends out (don't know much about that) and the amount of radiation that atmosphere can block. Due to it's higher gravitational pull it would have a thicker atmosphere than earth (I assume) and perhaps that could mean it coudl block out more radiation ?
However, this planet in itself might not be so important, but the following conclusion is:
The real importance is not so much the discovery of this planet itself, but the fact that it shows that Earth-like planets are probably extremely common in the Universe.
There are 200 billion stars in our galaxy alone and many astronomers believe most of these stars have planets.
The fact that almost as soon as we have built a telescope capable of detecting small, earth-like worlds, one turns up right on our cosmic doorstep, shows that statistically, there are probably billions of earths out there.
Even if only 10 billion stars are in a 'good' segment of the galaxy of the galaxy, if only one in ten of those have planets, if only one in ten of those have earth like planets and if only one in ten of those are capable of sustaining life (for whatever other reason the others can't) we're still looking at 10 million possible earths...
edyzmedieval
04-25-2007, 09:36
I can see my alien relatives!!! Yeeey! Haven't seen them since the Earth was born! :2thumbsup:
Ja'chyra
04-25-2007, 09:51
The Earth-like planet that could be covered in oceans and may support life
Seems to be a whole load of assumptions and no real evidence of what they are claiming.
There is no possible way humans could ever travel at light speed
and may be covered with large amounts of water - necessary for life to evolve -
I like how we base our assumptions on our limited knowledge and say that it must be so.
I don't think I'm alone when I say I'd like to see more and more planets fall under the ruthless domination of our solar system.
agreed.
i enjoy reading Peter F Hamilton wayyyy too much. :D
Vladimir
04-25-2007, 12:44
Does it have a magnetic field? Besides, the telescope that can detect what is claimed to be on this planet isn't going to be launched until 2020.
rory_20_uk
04-25-2007, 13:37
Woo hoo. A planet that is 20 light years away. We can't reach it, nor is that likely to change in the future.
The joy is that there is likely to be water on the surface.
Apart from helping Sci-Fi authors, what is the big deal about? Surely that China is polluting the Earth (you know - where we are) more than the USA is greater news.
Since this breakthrough, I suggest all funding for renewable fuels is scrapped, and we spend it all on shuttle launches and telescopes to see if there are any other watery rocks out there we can't reach.
~:smoking:
Gregoshi
04-25-2007, 14:32
Geez rory, your post is such a downer. I hope you're not suggesting that we stop all research on everything because we already know all there is to know. If anything, finding a planet like Gliese 581c sets another goal for us much like the new world did, or the ocean's depths or the sky or disease or war or any other challenge faced by mankind. Even if we can't go there physically (yet! ~;)), the better we can observe worlds similar to our own, the better we may be able to understand our own planet. Cheer up mate, it ain't all that bad! ~:pat:
Teleportation.
Teleportation? (http://en.wikipedia.org/wiki/Philadelphia_Experiment)
Vladimir
04-25-2007, 15:03
:laugh4: Rory I really want you as my doctor. You'd be cheaper than Kavorkian. :skull: :2thumbsup:
Since this breakthrough, I suggest all funding for renewable fuels is scrapped, and we spend it all on shuttle launches and telescopes to see if there are any other watery rocks out there we can't reach.
Very strange reaction. Space exploration usually helps us to refine/discover renewable energy and closed systems (i.e. "recycling"). Where do you think solar panels would be today if we hadn't needed them for satellites?
Also, most of the great liberalizations of civilizations have been made during periods of expansion and exploration. Societies that don't explore are more likely to become closed, calcified and xenophobic.
So I really don't understand why some environmentalists and anti-poverty activists get so dismissive about space exploration. Exploration and conservation are not enemies; they are symbionts.
And for those who say that we should end poverty, war, and All Bad Things before we spend a dime on checking out the Universe, may I point out that in the 6,000 years of our civilization nobody has been able to end All Bad Things, and yet we've achieved greatness anyway.
If you're worried about earth, mankind and suffering, just remember that the way out is forward, not sitting down and navel-gazing.
Found a planet several light years away, getting pounded with radiation, with unknown resources and hazards? Why is the answer always "send the drones, send the drones, they'll scope it out for us"? So predictable. :no: It's not like we wear red shirts.
Zaknafien
04-25-2007, 15:47
William Hill said it had shortened the odds on proving the existence of extraterrestrial intelligence from 1,000-1 to 100-1.
Wow, that's pretty damn good. SETI better get those radio-telescopes pointed the right way! they also mentioned by 2020 an orbital telescope could reach the planet.
Gregoshi
04-25-2007, 15:56
It's not like we wear red shirts.
<Gregoshi changes shirt>
Excellent post Lemur. :bow:
Rodion Romanovich
04-25-2007, 17:04
Damn, now they know where I came from ~:eek:
Damn, now they know where I came from ~:eek:
Don't worry, you have grown to big to put you back.
Mikeus Caesar
04-25-2007, 17:56
I read in the paper that the fastest ship we've ever launched went at about 24,000mph. At that speed, you'd arrive at Gliese in approximately 4.6 billion years time.
Somehow i don't think a generation ship will do.
KukriKhan
04-25-2007, 18:00
That is really neat, but being 13 times closer to it's radiatant star is bound to make for some radioactive environments. Not to mention, if there is sentient life there, evolving under 2g means they could kick our ass!
There's a thought. After taking 4 generations to get there (and just imagine the nature of the politics on-board that ship, across 100+ years), our traveling descendants find it hard to even move around on Nova Terra's gravity.
Then, turning the ship around to travel back to Sena Terra with our new-found friends, 200 years have passed, and out of that ship emerges Superman, able to leap tall buildings in a single bound...
The mind boggles.
Samurai Waki
04-25-2007, 18:55
If the Gravity is higher, wouldn't that just mean the likelihood of evolution would mean all the creatures would be pretty squatty and rotund compared to Earth Creatures?
Agent Miles
04-25-2007, 18:59
Actually, the “Goldilock’s Zone” is a rather outdated idea. If the Earth orbited in the giant star Betelgeuse’s GZ, then our seasons would be 60 years long. Venus and Mars were originally in the Sun’s GZ. Also, since we started looking for life out there, we’ve found organisms down here near undersea geysers that would melt lead and below the Antarctic snows, even in the radioactive furnaces of nuclear power plants. Life may be all over the universe. Life is necessary for intelligence to arise, however, intelligence is not necessary for life. There have been perhaps a trillion species on Earth. Only a handful could make a campfire.
As for going there, it’s actually quite practical. An orbital laser, powered by the sun, can propel a “light sail” spaceship with the pressure of light rays. Accelerating gradually for about a year, the ship would reach 10% of the speed of light (c). Thus in two centuries, we could travel to this new world.
If we slowly colonized even just one other star every thousand years, and these colonies did as well, then we could populate the entire galaxy in a few thousand centuries. There are no uninhabitable regions. People in Dyson rings could live anywhere there is light from a star and space rubble to build with.
Similarly, since no one else has colonized our star system, this means that there is no intelligent life in the galaxy that is at least a half a million years ahead of us (or they would be here). There are also no lesser civilizations in our immediate region either, for the same reason.
Rameusb5
04-25-2007, 20:15
My greatest regret has been being born in a time where we are aware of the scope of the universe, but unable to explore it.
Heck, we haven't even made a manned expedition to the nearest planets yet!
BTW, space exploration should be mankind's primary endeavor. We already know the sun is going to burn out and when it does, Earth will become uninhabitable. Why wait till the last minute to find somewhere else to go?
We've only got a few billion years left!
Vladimir
04-25-2007, 20:16
As for going there, it’s actually quite practical. An orbital laser, powered by the sun, can propel a “light sail” spaceship with the pressure of light rays. Accelerating gradually for about a year, the ship would reach 10% of the speed of light (c). Thus in two centuries, we could travel to this new world.
With the growth of technology I can just imagine those poor saps on a sail ship getting passed up by the next big advancement in propulsion. After 100 years drifting in space all they could do is press their noses against the window and think: “WTF!”
Found a planet several light years away, getting pounded with radiation, with unknown resources and hazards? Why is the answer always "send the drones, send the drones, they'll scope it out for us"? So predictable. :no: It's not like we wear red shirts.
Just worry about keeping the Queen happy. I hear ya'll are a dying breed.
King Henry V
04-25-2007, 20:32
Good news, though it will probably not amount to much in our lifetimes, or even in our children's lifetimes. However, it is nice to think that for once we don't have to be the poor losers who get crushed by the highly developed aliens, something which I have believed all along (I mean, someone has to be first).
Rameusb5
04-25-2007, 20:46
LOL... my thoughts exactly. Early space travel will surly be frustrating as hell.
I'm not sure of the practicality of it, but there was a type of spacecraft proposed called a "Ramjet" that collected fuel (hydrogen) from space as it travelled. Thus, it had infinite fuel and therefor could constantly accelerate.
So, if one set the accelleration rate (thrust) at 9.8 meters per second squared (1 G), you would have "simulated" gravity on your ship, with "up" being the direction of travel. You would proceed in this manner until you reached the halfway point, at which time you'd turn the ship around and start DECELERATING at 1G until you arrived at your destination.
You could actually go pretty fast doing that. If my calculations are correct (and I'm guessing they aren't), you could get halfway there (10 lightyears) in 105 years. So it would take about 2 centuries at 1G.
If you up it to 1.5 G, it would only take a total of about 170 years.
2G's... 150 years.
I doubt you could go beyond 2 G's without REALLY screwing up people's physiology...
Edit - On the halfway point of your journet (fastest V), you'd be travelling 1352106000 meters per second! That's 4,867,581,600 km/hr! (That's 4.8 trillion kph!)
Ironside
04-25-2007, 21:17
That is really neat, but being 13 times closer to it's radiatant star is bound to make for some radioactive environments. Not to mention, if there is sentient life there, evolving under 2g means they could kick our ass!
It also emitts way lower levels of UV-radiation so I'm not sure exactly what kind of radiation they're talking about.
To put it differently, even without an ozone layer, it would be very hard to get sun-tan on Gliese 581 c.
Don Corleone
04-25-2007, 21:23
I understand it's got a lot lower levels of upper band electromagnetic radiation. But my point is that the intensity of energy experienced by a target receiving waves of said EMR decays with the square of the distance between them. So, if it's 13 times closer, it receives 169 times the energy, assuming a similar source. Your point is that UV and other upper band EMR will be lower intensity at the source is valid, but is it enough to counteract that scaling factor? There's going to be some gamma emission from Gilese 581. Would you want to be 6.2 million miles away from it when you could be 93 million miles away?
Ironside
04-25-2007, 21:45
I understand it's got a lot lower levels of upper band electromagnetic radiation. But my point is that the intensity of energy experienced by a target receiving waves of said EMR decays with the square of the distance between them. So, if it's 13 times closer, it receives 169 times the energy, assuming a similar source. Your point is that UV and other upper band EMR will be lower intensity at the source is valid, but is it enough to counteract that scaling factor? There's going to be some gamma emission from Gilese 581. Would you want to be 6.2 million miles away from it when you could be 93 million miles away?
The scaling factor = 169, the reduction of 100nm UV-radiation is = 473 million (I checked more than once to make sure the formula was correct, that felt like alot), unless I misunderstood Planks radiation law somehow.
Sun was 5800K, while the red star was 3300K.
So unless there's some gamma radiation thing happening in the sun that isn't black-body emittance there isn't any radiation to talk about.
The place will be very dark though, the middle of the day will be like twillight here on earth.
Edit: Hmm just remebered something. The strongest radiation should come from the center of the star, so I would need to have temperatures on the center to get a basis for value of the gamma radiation, who in turn should get partially absorbed by going through the star. Complications, complications...
ZombieFriedNuts
04-25-2007, 21:58
13 day solar orbit thats one fast planet
Samurai Waki
04-25-2007, 22:03
Well You also have to take into account that the Gilese Sun isn't very big. Which means its probably ridiculously dense at the core, meaning higher gravitational pull, and a small likelihood that Gamma Radiation could easily escape and bombard the planet. Plus, if it even has a viable atmosphere, then Gamma Radiation shouldn't be a problem anyways.
Sweet! At first I thought the article was a prank, but I'm very pleased that it's not. I don't care that I'll be long dead by the time we're able to trave outside of our own solar system -- I'm still excited anyway. :jumping:
I volunteer to be the first one to mate with our new alien buddies.
But what if they reproduce through budding?
So we can all relax then, its ok weve found another world, which a few select individuals cans colonize after weve finished turning this one into a radioactive ball of dust
Id suggest we send celebritys and make a game show out of it
Celebrity colonization of the stars
doc_bean
04-26-2007, 08:12
I do hope we start some serious space expoloration and exploitation soon, remember :
"United we stand, divided we welcome our alien overlords !"
HoreTore
04-26-2007, 12:39
I find it funny how people believe that the life we have here is the only way to make life. The fact is, however, that we do not know of any other ways for life to exist than here. That doesn't mean that life cannot form other places at 500 degrees with acid rain and no oxygen... It's just as likely for life to form at such a place as here, IMO.
TevashSzat
04-26-2007, 13:04
Horetore is quite right and some have theorized that life forms on another planet could be based off of silicone instead of carbon creating some very wierd looking creatures
Agent Miles
04-26-2007, 14:54
The Drake equation states that:
N=R*x fp x ne x fl x fi x fc x L
where:
N is the number of civilizations in our galaxy with which we might expect to be able to communicate at any given time
and
R* is the rate of star formation in our galaxy
fp is the fraction of those stars that have planets
ne is average number of planets that can potentially support life per star that has planets
fl is the fraction of the above that actually go on to develop life
fi is the fraction of the above that actually go on to develop intelligent life
fc is the fraction of the above that are willing and able to communicate
L is the expected lifetime of such a civilization for the period that it can communicate across interstellar space.
This discovery helps fine tune the third variable. There could be exotic life on lots of planets and moons, even on the surface of cool brown dwarf stars. However, Drake made the conservative argument that we know there is life on Earth, so how many Earth-like planets might there be in the galaxy? Some of the other variables can be estimated to get just about any result you want.
P.S. Rameus-You’re right, except that your ship accelerated past the speed of light! (approximately 300,000,000 m/second) The ramjet design requires a ship that is miles long with a scoop several miles wide. However, you could go anywhere in the universe in your lifetime (the rest of the universe would age billions of years).
Vladimir
04-26-2007, 15:47
Horetore is quite right and some have theorized that life forms on another planet could be based off of silicone instead of carbon creating some very wierd looking creatures
Fat chance (http://www.daviddarling.info/encyclopedia/S/siliconlife.html).
Rameusb5
04-30-2007, 19:40
P.S. Rameus-You’re right, except that your ship accelerated past the speed of light! (approximately 300,000,000 m/second) The ramjet design requires a ship that is miles long with a scoop several miles wide. However, you could go anywhere in the universe in your lifetime (the rest of the universe would age billions of years).
I've never been able to get my head around FTL travel, but from my (extremely n00bish) understanding, the passengers of the ship would be able to go that fast just fine.
It would just appear (to observers) to take forever to do so to observers.
I've always been rather annoyed that the laws of physics that I have grown so accustomed to totally break down on the extreme ends of reality (the very fast and the very small).
Soulforged
04-30-2007, 20:09
Very good news Lemur. Probably I won't see this planet ever... That's until I've finished my elixir or youth of course...
Anyway, the human always finds a way through dreams and hopes, in this news expands our limits in this world probably beyond actual paradigms.
doc_bean
05-01-2007, 09:47
Not that I'm an expert (physicists and expert please correct me if I'm wrong)...
I've never been able to get my head around FTL travel, but from my (extremely n00bish) understanding, the passengers of the ship would be able to go that fast just fine.
Reaching that speed would be extremely hard I think. There's a reason light is massless, I don't think that anything with a mass could reach that speed. I think it's an asymptotic speed, it would take more energy to achieve the same acceleration closer to light speed. (I may be completely wrong here).
It would just appear (to observers) to take forever to do so to observers.
Well, we do see light from distant stars, so it can't take forever for an outside observer, otherwise we'd never see anything that travels at light speed.
Ironside
05-01-2007, 11:18
Well, we do see light from distant stars, so it can't take forever for an outside observer, otherwise we'd never see anything that travels at light speed.
For the observers, the speed is easy to handle, 99% of the light speed means 99 light years in 100 years, while it's a much shorter time on board the space ship.
But as 99 light years is nothing in the universe... Traveling to the Andromeda galaxy for example, 2,5 million years...
There's a reason light is massless, I don't think that anything with a mass could reach that speed.
IIRC black holes drag light into them, black holes have a whole lot of gravitational pull and gravitation affects mass, thus light would not be massless. IIRC light is more like mass converted to energy, because mass and energy are roughly the same etc. pp. never really understood that completely myself.:sweatdrop:
Ironside
05-01-2007, 15:59
IIRC black holes drag light into them, black holes have a whole lot of gravitational pull and gravitation affects mass, thus light would not be massless. IIRC light is more like mass converted to energy, because mass and energy are roughly the same etc. pp. never really understood that completely myself.:sweatdrop:
No, no, no light only got momentum, that makes it act like it actually had mass, because if light had mass, the photons would gain unlimited mass and would instantly collaps into black holes and instantly create the big crunch (giant black hole that contains the whole mass of the universe). :dizzy2: :laugh4:
Things start to get very complicated around there, probably due to imcomplete theories.
The_Mark
05-01-2007, 16:35
Hehe.
Reaching that speed would be extremely hard I think. There's a reason light is massless, I don't think that anything with a mass could reach that speed. I think it's an asymptotic speed, it would take more energy to achieve the same acceleration closer to light speed.
Yes. When an object accelerates its mass grows without limits, and accelerating the object will therefore take more and more energy. With ridiculous amounts of energy we could accelerate an object ridiculously close to the speed of light, but actually reaching c would take infinite energy, and since the mass increases the accelerated object would collapse into a black hole at some point. Not to mention that our ridiculously fast and therefore heavy object could scoop up some objects en route in its gravitational pull. Now, I wouldn't want a bleedin' planet tailing me when I'm about to decelerate. :beam:
Lorenzo_H
05-01-2007, 17:10
I have been watching DVDs on Aliens and stuff and its very possible that they do exist. I won't bother going into details unless someone asks me.
Louis VI the Fat
05-02-2007, 01:17
IIRC light is more like mass converted to energy, because mass and energy are roughly the same etc. pp. never really understood that completely myself.:sweatdrop:I'm not really sure about that myself. But lately I've been pondering about this subject quite a bit, and I've come up with this...equation - if it deserves that name. I have this feeling, and it's a hunch more than anything else so please don't laugh, but perhaps energy could be equated with mass times the speed of light squared? :sweatdrop: What do you guys think?
Oh, and since this planet is discovered by a team of French astronomers, with the odd Swiss French thrown in, I naturally demand that all communications with any posible aliens be conducted in French.
Gah! So we couldn't get you earthlings to submit to our linguistic demands, eh? We'll just teach the aliens then. While you lot are still wasting your time discussing robot poodles, rabbits and Drake's equation, we are transmitting signals to Gliese and are well on our way to turning the universe francophone. :yes:
Vladimir
05-02-2007, 01:54
I love the Science channel!
I was had it on after I got back form work and I believe some goofy looking Frenchman was the first one to discover a planet around another star, a hot Jupiter. :book:
Divinus Arma
05-02-2007, 02:40
Two thoughts:
(a) Cool!
(b) Rather than working on a faster means of travel, why not work instead, or simultaneously, on a means of extending life. 200 Years of travel is more tolerable if one lives to be 300 or more. With genetics controlling the aging process, it seems we are far closer to this than the former.
Papewaio
05-02-2007, 03:49
Oh, and since this planet is discovered by a team of French astronomers, with the odd Swiss French thrown in, I naturally demand that all communications with any posible aliens be conducted in French.
Gah! So we couldn't get you earthlings to submit to our linguistic demands, eh? We'll just teach the aliens then. While you lot are still wasting your time discussing robot poodles, rabbits and Drake's equation, we are transmitting signals to Gliese and are well on our way to turning the universe francophone. :yes:
Well then the most appropriate phrase given pop culture and the language chosen would have to be:
"We welcome our new Alien Overlords."
I have this feeling, and it's a hunch more than anything else so please don't laugh, but perhaps energy could be equated with mass times the speed of light squared? :sweatdrop: What do you guys think?
That sounds nice, but it can only be wrong if light has no mass, then it's mass would be zero, and you'd end up with it's energy = 0*c² = 0, but IIRC light does have energy, think of laserbeams and sunburns. ~;)
Vladimir
05-02-2007, 12:55
Two thoughts:
(a) Cool!
(b) Rather than working on a faster means of travel, why not work instead, or simultaneously, on a means of extending life. 200 Years of travel is more tolerable if one lives to be 300 or more. With genetics controlling the aging process, it seems we are far closer to this than the former.
If you can find a way to stop DNA from disentegrating after X number of divisions, you'd be my hero. For right now, let's work on fusion generators.
doc_bean
05-02-2007, 14:49
That sounds nice, but it can only be wrong if light has no mass, then it's mass would be zero, and you'd end up with it's energy = 0*c² = 0, but IIRC light does have energy, think of laserbeams and sunburns. ~;)
E=mc^2 is a conversion law I believe. For instance with a nuclear bomb you lose a little bit of mass and gain a lot of energy, the mass is turned into (massless) energy. I don't think it means you need mass to have energy.
Don Corleone
05-02-2007, 15:52
That sounds nice, but it can only be wrong if light has no mass, then it's mass would be zero, and you'd end up with it's energy = 0*c² = 0, but IIRC light does have energy, think of laserbeams and sunburns. ~;)
If I remember my Electormagnetics properly, you don't calculate the energy of a waveform using that E=mc^2 equation, that just tells you what amount of energy you'll get out of a mass converted to energy.
In order to get the energy of a waveform, according to the esteemed Frenchman Msr. Parseval: https://img.photobucket.com/albums/v334/tharris00/03equ14.gif
No mass required. I think theoretical physicists go around and around over whether photons have mass or not, but it's not required for them to have mass in order to have energy.
Are these the robotic lemurs you had stashed away, along with Kommodus' nano-bots?
ooh ooh, give them robots some ancient weapons too!
Well The theory of blackholes supports that light has mass, be it a very small one. Also the way we calculate the masses of galaxies is, if I'm not mistaken, also based on the fact that photons have a mass.
However like The Mark said, he is a physisist (or however you write it) I believe, making an object move to a speed approximate to the speed of light is practically almost impossible. The mass it'll get will be enormous, the energy required too. Not only is it hard to get it so fast, controlling it (deccelerating, it's gravity,...) must be even harder.
Also if someone would want to reach the planet it would take quite a while. It can't take much more than 20 years for the person if he'd want to get back to earth afterwards.
So how what average speed will his craft then need to get there in 20 years?
20years=(c*20.5years)/v
<=> 20years*v=(c*20.5years)
<=>v=c*20.5years/20
<=>v=1.025*c
=> v>c!!
SO that seems rather impossible now if the objective would be to get a person over there (without the person having to come back) let's say we have a max of 40 years.
=>v=20.5/40*c
=>v=0.512*c=153 493 738 m / s
this seems theoretically possible but how much energy would that need?
E=0.5*m*v²
That would be: 76746869 times the mass of the object. let's have a round number, what about 500kg?
then 76746869*500kg=38 373 434 500 J
Now is this much or not?
Well let's see:
How much E does it cost to take a car to 120km/h?
well lets see how much does a car weigh? I've taken the mass of an empty Ford Fusion 1.4 TDCi Fusion+
Well that would take this much energy:
1102 kg*120²km²/h²*0.5=7 934 400 J
38 373 434 500J/7 934 400J=4 836.33728
That would mean we'd need the E of 4 836.33728 Empty Ford Fusions accellerating from 0 to 120km/h (without friction that is. But the craft wouldn't have friction either it being in space.)
So Daily we have millions and millions of cars doing this, mulitiple times a day so this seems possible. E might not be the biggest problem in this case. However this of course overly simplified and stuff so it probably is far from correct however it might give us an idea of the actual numbers. And it seems to me that E isn't the biggest problem if we want to send someone to there without him or her having to come back.
Zaknafien
05-02-2007, 21:51
Well can't ion drives reach something like 'near' the speed of light if given enough time to accelerate? My understanding was that something with ion drive, like the one tested on some probe a year or two ago, will continuously accelerate until it reaches 99.9% of the speed of light but it would take many years to get going that fast..
Rameusb5
05-03-2007, 18:55
Well The theory of blackholes supports that light has mass, be it a very small one. Also the way we calculate the masses of galaxies is, if I'm not mistaken, also based on the fact that photons have a mass.
However like The Mark said, he is a physisist (or however you write it) I believe, making an object move to a speed approximate to the speed of light is practically almost impossible. The mass it'll get will be enormous, the energy required too. Not only is it hard to get it so fast, controlling it (deccelerating, it's gravity,...) must be even harder.
Also if someone would want to reach the planet it would take quite a while. It can't take much more than 20 years for the person if he'd want to get back to earth afterwards.
So how what average speed will his craft then need to get there in 20 years?
20years=(c*20.5years)/v
<=> 20years*v=(c*20.5years)
<=>v=c*20.5years/20
<=>v=1.025*c
=> v>c!!
SO that seems rather impossible now if the objective would be to get a person over there (without the person having to come back) let's say we have a max of 40 years.
=>v=20.5/40*c
=>v=0.512*c=153 493 738 m / s
this seems theoretically possible but how much energy would that need?
E=0.5*m*v²
That would be: 76746869 times the mass of the object. let's have a round number, what about 500kg?
then 76746869*500kg=38 373 434 500 J
Now is this much or not?
Well let's see:
How much E does it cost to take a car to 120km/h?
well lets see how much does a car weigh? I've taken the mass of an empty Ford Fusion 1.4 TDCi Fusion+
Well that would take this much energy:
1102 kg*120²km²/h²*0.5=7 934 400 J
38 373 434 500J/7 934 400J=4 836.33728
That would mean we'd need the E of 4 836.33728 Empty Ford Fusions accellerating from 0 to 120km/h (without friction that is. But the craft wouldn't have friction either it being in space.)
So Daily we have millions and millions of cars doing this, mulitiple times a day so this seems possible. E might not be the biggest problem in this case. However this of course overly simplified and stuff so it probably is far from correct however it might give us an idea of the actual numbers. And it seems to me that E isn't the biggest problem if we want to send someone to there without him or her having to come back.
The problem with your reasoning is that you have a constant velocity. You can't subject the Human body to very high G's for long periods of time. It'll take you a while just to accellerate to 1/2 the speed of light (to use your analogy). Ideally, you'd use around 1 G of accelleration to simulate gravity on your ship. The speed of light = 299,792,458 m/s. So to reach .5 lightspeed at 1 G would take 11.65 years! You'd need exactly the same amount of time to slow down as well.
Let's face it, extra-solar space travel using conventional physics just isn't practical.
Hence my concern about the sun burning out some 2-5 billion years from now. Will we be advanced enough to escape by then?
Somebody Else
05-03-2007, 19:16
Is it flat too?
The problem with your reasoning is that you have a constant velocity. You can't subject the Human body to very high G's for long periods of time. It'll take you a while just to accellerate to 1/2 the speed of light (to use your analogy). Ideally, you'd use around 1 G of accelleration to simulate gravity on your ship. The speed of light = 299,792,458 m/s. So to reach .5 lightspeed at 1 G would take 11.65 years! You'd need exactly the same amount of time to slow down as well.
Let's face it, extra-solar space travel using conventional physics just isn't practical.
Hence my concern about the sun burning out some 2-5 billion years from now. Will we be advanced enough to escape by then?
I know it was a very simplification, noting that E wouldn't be that much the problem, rather the speed itself.
Divinus Arma
05-04-2007, 05:27
Do the inhabitants of Gliese 581 C need to have their souls saved? We better hurry up and get some missionaries over there to preach the good news!!!!
Seriously, what would be the theological implications of intelligent extraterrestrial life? Not as in an argument for or against the existence of God, but rather the implications for the earth-based interpretations of God's will: Muhammed as the prophet (does this apply to the universe?), and Jesus as saviour (same question.).
All the myth and legend, the puff and stuff, of earthly religion kinda goes out the window, wouldn't ya say?
The theological implications of intelligent life outside our solar system would be profound. Let's make this easier and consider which religions would not freak out. I think Jews would be okay; aliens don't change their status as God's Chosen. Buddhists would fare well. Scientologists already believe in an intergalactic empire, so their worldview would not shatter. Not sure about Mormons -- they believe in other planets, and they already have Jesus making a trip to the native Americans, so I guess it wouldn't be a stretch to say that Jesus might have stopped off at other civilizations along the way.
Can't think of many more. Fundamentalists of the Big Two would have serious issues.
Assuming whatever intelligence we eventually contact is mortal (and no some self-dividing amoeba thingy that never really dies), it's safe to expect that it will have its own religion already. I can't imagine a self-aware, mortal species not developing a what-happens-when-we-die scenario with all of the attendant theology.
doc_bean
05-04-2007, 10:23
Seriously, what would be the theological implications of intelligent extraterrestrial life?
We shall argue whether the war against these abominations should be termed acrusade or a jihad.
Seriously, religions have endurance, while the implications would be profound, I can't see this as being the end of religion or something like that.
I think the Catholic church would start by caling together a bunch of theologians and letting them think about the implications for 20years or so, after that time, the Church would have a good idea of how society thinks about these aliens and will formulate a point accordingly. They might call for missionary missions if they are plausible.
The various protestant cults (heh, no offence people) will react differently, like they always do, a few of them will probably split up (again) over this. Creationists will claim the aliens are a test of our fate, probably.
The Jews won't care, most Muslims won't either I think, they are , after all, also a sort of 'chosen people'.
Ironside
05-04-2007, 11:05
Hence my concern about the sun burning out some 2-5 billion years from now. Will we be advanced enough to escape by then?
First, we can "easily" do a generation ship today if we wanted to, second, if we have decandants at that point, it would still be very hard to claim them as humans... How was life a billion year back in time?
Since when do we send missionaries to elephants and giraffes?
If God created aliens, he will surely have his plans for them and I don't know why I should be concerned about these plans, that's my opinion. Then again, we have yet to discover intelligent aliens, once we have, I can talk to them about the issues at hand, no?:sweatdrop:
The_Mark
05-04-2007, 15:14
Well The theory of blackholes supports that light has mass, be it a very small one.
Light doesn't have mass, only momentum derived from its energy*. The thing with gravity and light is that even though light travels straight, uninfluenced by the gravity, the space itself in which light travels is curved by the gravity. So the photons think they're going in a straight line, and they're right, but everybody else thinks they go in a curve. And they're right as well. Simple, yes?
Yeah, I don't get it either.
However like The Mark said, he is a physisist (or however you write it) I believe,
I'm not a physicist, yet. In fact, I sent my application to University of Helsinki today, to the department of physics.
First, we can "easily" do a generation ship today if we wanted to, second, if we have decandants at that point, it would still be very hard to claim them as humans... How was life a billion year back in time?
And they will probably be greeted by a thriving human colony established by the first human visitors of Gliese, who left 200 years after the generation ship, using some snappy anti-matter propulsion.
*)
Photon's energy E = hf = hc/λ
photon's momentum p = E/c
Never heard of Parseval.
Ironside
05-04-2007, 16:07
And they will probably be greeted by a thriving human colony established by the first human visitors of Gliese, who left 200 years after the generation ship, using some snappy anti-matter propulsion.
This "paradox" gets even funnier if they're traveling near the speed of light, then you can have the same persons that borded the ship to be 200 years late. Poor buggers :no:
Point was, that we can evacuate "humanity" within a few years if things go badly. That I wouldn't recommend it unless you're very, very desperate (and the sun turning too hot or into a red giant would be such a thing) is another matter.
Who needs all those equations and difficult formulas when the only thing you need to get there is some LSD...
:hippie:
Who needs all those equations and difficult formulas when the only thing you need to get there is some LSD...
:hippie:
2 words: Hawaïaanse paddo's.
Light doesn't have mass, only momentum derived from its energy*. The thing with gravity and light is that even though light travels straight, uninfluenced by the gravity, the space itself in which light travels is curved by the gravity. So the photons think they're going in a straight line, and they're right, but everybody else thinks they go in a curve. And they're right as well. Simple, yes?
special relativity combined with general relativity that is? Hmmm...
Oh well it's not my job to figure out a way to get there. I'm not a superhuman, like them Japanese.
Well can't ion drives reach something like 'near' the speed of light if given enough time to accelerate? My understanding was that something with ion drive, like the one tested on some probe a year or two ago, will continuously accelerate until it reaches 99.9% of the speed of light but it would take many years to get going that fast..
an ion-drive, as we currently understand them, is capable of a maximum of ~100,000 MPH, roughly four times faster than the limit of chemical combustion, i.e. rockets.
they are a bit lacking in thrust however.
ShadeHonestus
05-10-2007, 09:44
I'll bet somebody $20 dollars that human beings will cease to exist prior to our capacity for interstellar travel (in my view impossible for an individual) or the end of earth with its consumption by our sun which should take place in about 4 billion years as the sun's size increases near its death.
I'll even give 1,000,000,000,000:1 odds.
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