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First Rocky Exoplanet Confirmed
Matt_dk writes "The confirmation of the nature of CoRoT-7b as the first rocky planet outside our Solar System marks a significant step forward in the search for Earth-like exoplanets. The detection by CoRoT and follow-up radial velocity measurements with HARPS suggest that this exoplanet has a density similar to that of Mercury, Venus, Mars and Earth, making it only the fifth known terrestrial planet in the Universe. The search for a habitable exoplanet is one of the holy grails in astronomy. One of the first steps towards this goal is the detection of terrestrial planets around solar-type stars. Dedicated programs, using telescopes in space and on ground, have yielded evidence for hundreds of planets outside of our Solar System. The majority of these are giant, gaseous planets, but in recent years small, almost Earth-mass planets have been detected, demonstrating that the discovery of Earth analogues — exoplanets with one Earth mass or one Earth radius orbiting a solar-type star at a distance of about 1 astronomical unit — is within reach."
What do I win
k, it's 2025, we've found a rocky planet around a Sun-like star with a year and day like ours. we've measured the atmosphere and it is nitrogen/oxygen with the right proportions and we've even manged to image it and gotten more than 4 pixels. What now?
let's image the surface! yeah! we see green trees and blue oceans and, oh my, are those roads? is that a city? How far away is this rock? hmmmm.
How we know is more important than what we know.
I appreciate the Rocky movies and all, but there's no way I would live on a whole planet dedicated to them. I'm fine here on Earth, thank you very much.
My webcomic
By the time we actually got to one of these planets, would it still be able to sustain life? Should we be looking for planets that are in their early, less habitable stages?
Buckle your ROFL belt, we're in for some LOLs.
Looks like this little guy is only 0.002 AU away from it's parent star. I wouldn't expect to find any life there, but still, this is an amazing discovery. As these methods get fine tuned it's only a matter of time before we start finding planets roughly Earth-like not only in form, but also in relation to the habitable zone around their star. I don't think we'll ever get a probe, much less a person, to any of them within my lifetime, but at least we'll have an interesting list of spots to visit when we do reach that capability :).
"People who think they know everything are very annoying to those of us who do."-Mark Twain
Is it class M?
It might have Roddenberries.
By then we'll be living in space and the presence or absence of "habitable worlds" will be moot. We will once again be going beyond the next horizon because "it's there".
Help stamp out iliturcy.
Smallest maybe, and the first to have a confirmed radius value, but hardly the first rocky exoplanet discovered. PSR 1257+12 wins by about 18 years.
Here's a scientific paper describing how the period/mass/size/etc of the planet was deduced from observation data: http://arxiv.org/abs/0908.0241
According to the paper, this planet's orbital semimajor axis (or in plain English, the "average" distance from the planet to the sun) is about 0.0172 astronomical units. Since its sun's temperature is roughly at the level of our Sun (also in the paper), it means the planet is probably a hell much hotter than the Earth...
Colorless green Cthulhu waits dreaming furiously.
... that is the CoRoT needed to keep the donkey going...
I'm packing my bags
factor 966971: 966971
.... watch me pull a planet out of my hat!
Also known as Balboa.
Stupidity only gets you so far, then you've gotta try
I'm sorry, I thought this article was about Stallone, in space.
...What about Bullwinkle?
-1, Disagree is not a valid option. Troll, Flamebait and Offtopic are not a substitute.
Maybe jump to the left?
Then a step to the right, perhaps?
General Relativity dictates that nothing can travel faster than light, and that the speed of light is constant in every frame of reference. Therefore, although we measure distance in light years, it doesn't lead to twice the duration if we traveled at half the speed of light. In fact, as we approached relativistic speeds, the duration within our frame of reference would stay the same, but from an external point of view, our speed has not actually reached such a velocity. Therefore, we would perceive the time to travel to a nearby star as shorter than the value arrived at by a simple ratio applied to c. Likewise, the actual time passed on the target planet will have been many times longer by the time we get there such that we cannot assume that millions of years haven't passed since we first set out from our own home planet.
This kind of craziness is why people would rather study QM than GR.
Thinking wastes energy and adds to entropy. Better to run on instinct, programming, or blind hormone-induced rage.
Here's to hot beer, cold women, and Glaswegian kisses for all.
Therefore, although we measure distance in light years, it doesn't lead to twice the duration if we traveled at half the speed of light. In fact, as we approached relativistic speeds, the duration within our frame of reference would stay the same, but from an external point of view, our speed has not actually reached such a velocity.
Um, what? If it's 500 ly away, and something goes there at c/2, it takes 1000 years. What else could a speed of "half of lightspeed" possibly mean? Even relativity isn't so weird as to change that.
Therefore, we would perceive the time to travel to a nearby star as shorter than the value arrived at by a simple ratio applied to c. Likewise, the actual time passed on the target planet will have been many times longer by the time we get there such that we cannot assume that millions of years haven't passed since we first set out from our own home planet.
You're right that the passengers on the trip would experience less proper time than the observers on Earth (I believe this is really due to the acceleration involved, although it can be calculated using SR). But the time as measured by clocks on Earth and the destination will still be the one millennium you would expect from Newtonian physics. (What would surprise Newton is the anomalously large energy required to get to that speed, and the bizarre view out the window had by the travellers.)
In the grand tradition of selling things you don't own, like the names of stars and acres on the moon, I hereby offer to sell 40 acre lots on this planet for a mere $10,000 each. That's cheaper than a lot this size would cost in any large city here on earth. Imagine what you could do with your lot. Since there isn't any law enforcement there yet, you could grow illegal crops, build a manufacturing plant without any polution controls, or just use it to test your nuclear bombs. This is a limited time offering, and quantities are limited, so don't delay. And if you order today, we'll include the plans for a trebuchet so you can fling dead animals onto your neighbors property.But wait, order during this program, and we'll include a set of ginzu knives (shipping, handling, and other fees are an additional charge) which can cut through the toughest tomato without the need for a hammer, but you'll want to use one anyway just for the splattering fun.
Who would win this election: Andrew Weiner vs Andrew Weiner's weiner.
Such a planet already exists... it's called Philadelphia.
I happen to be an inhabitant of said planet. My name is Adrian, I welcome you to my world.
Dead serious, yes, my name is Adrian, and in fact, in my high school there was a also a guy named Rocky, and we were both in marching band and our band once performed "Gonna fly now." Such is the life on my planet, even though I'm a guy.
*goes back to watching sports and eating cheesesteaks*
"All great wisdom is contained in .signature files"
If you assume that only most of, say, a 1000 light year journey takes place at 0.5c (so the trip will take 2 or 3 or 4 thousand years, assuming some clever sort of acceleration is worked out), the rest frame (the planet you launched from) will only be experiencing time about 15% faster than the ship, so only 2,300, or 3,450, or 4,600 years will have passed by the time you get to the other planet (or so).
That's still too long. The sensible way to measure velocities is in the frame of the source and destination (which might as well be in one frame when we're talking about SR), so you can calculate the travel times in that frame directly by dividing the distance by the velocity. The only weirdness is the amount of time observed by the travelers, which is smaller than that observed by the endpoints, but not because the latter amount is increased beyond what Newton would expect.
Whether it's a nearby supernova bathing the planet in radiation for years, or a rogue comet or asteroid impact - whether it's man's inhumanity to Mother Earth or a return of the periodic glaciation which has been Earth's habit these last billion years, or something else, the Earth will become uninhabitable by humans eventually.
I've always wondered why some people seem to think it inevitable that the entire human race will forego living on planets.
At the time I've described above if there aren't human colonies off this rock it's game over for the human race. Life will go on, but it won't be us. All humans may not forego living on planets, but some by necessity must. Or we won't, and there'll be nobody left to call me a liar.
Help stamp out iliturcy.
Meanwhile, as scientists on an outer planet look our way:
"Rocky planets like the one recently discovered are turning out to be quite common throughout our area of space. Given a dense enough atmosphere, this planet could even support life like ours, although it's hot enough to kill all but the most tolerant extremophiles known. Spectroscopic analysis, though, reveals its deadly nature: much of its surface is covered with molten hydroxic acid, which forms toxic clouds and then falls as corrosive rain. If life-giving ammonia was ever present on the surface, it's long since combined with the abundant free oxygen in the atmosphere. Our chemists are still uncertain what could produce so much free oxygen; fantasists have speculated on forms of life that would metabolize oxygen in the same way that we metabolize hydrogen, but the analogy breaks down quickly as you look more closely at the chemistry involved."
Great... we can go there and take THEIR oil.
That's three reasons why we should do it. Got any more?
Help stamp out iliturcy.
Soon to be followed by Rocky 2, Rocky 3 and Rocky 4. All of which will suck.
Confucius say, "Find worm in apple - bad. Find half a worm - worse."
Joking aside, if we found an exoplanet, with earthlike environment that would be completely amazing and would have interesting philosophical implications. If we found such a planet with life on it, that has profound implications. If we found a planet with roads and a city - civilisation, that has truly astonishing implications for our entire culture.
...And once we got over that momentous wonder and awe, we would have to go kill them.
HA! I just wasted some of your bandwidth with a frivolous sig!
This planet is too big, too close to its Sun, and orbiting too fast to be habitable in any way we are accustomed too. But this doesn't mean its discovery is not news: Astronomers are finding more evidence that planets are common. Progress is being made towards discovering planets more like our own than the gas giants which were first discovered.
What is needed is more telescopes of good sensitivity. Each main sequence star not wholly unlike our own needs to be carefully monitored over time, in order to detect planetary crossings, and then focus the best telescopes on the most promising stars.
The summary (and TFA too ;-) reminded me of the recent debate over the definition of "planet".
One obvious problem is with the claim that we only knew of four "rocky planets" before this one. Since Mercury and Mars are included, it's likely that the definition they're using would also classify at least Titan and Triton as "rocky planets", giving us six.
But, (I can hear people saying), Titan and Triton aren't planets because they don't orbit the sun. Well, neither does this new planet; it orbits another star. Some people have seriously defined "planet" to mean objects that orbit our sun, and of course that definition immediately says that there can't be any more planets in the rest of the universe. If you accept this new object as a "rocky planet", what's your definition? You'll have to word it very carefully so that it includes things orbiting a distant star, but not those that are in orbits around local gas giants.
And if you find a good wording for that, you face another likely future problem: How small an object is allowed as the primary? Suppose a new rocky-planet-like object is found in orbit around a nearby "brown dwarf". The primary isn't a proper star, so is the object merely a moon and not a planet? It's also likely that we'll soon find Jupiter-class objects in free space, not orbiting a star; if one has a Mercury- or Mars-like object in orbit, would it be classified as a rocky planet or a moon? If it's a planet, then why isn't Ganymede also a planet?
I'd predict that in the not-too-distant future, as smaller things can be detected remotely, astronomers might decide to abandon such definitions that depend on the type of primary, and rewrite definitions so that they only use properties of the object itself. Either that, or they'll deprecate "planet" as a lay term that's not useful for scientific purposes. Dunno what they'd replace it with, though.
Meanwhile, the Sophists amongst us may be in for a lot of fun in the near future. Those of us who sat at the sidelines chuckling over the angst caused by the demoting of Pluto are probably looking forward to a lot more astronomical geek humor in the next few years.
Those who do study history are doomed to stand helplessly by while everyone else repeats it.
For the state of the bottoms Butt be a lot slower NIGGER community the channel to sign unpleasant FreeBSD at about 80 consider that right for a living got juggernaut either
Let's assume that, when we find this planet, it is the closest habitable planet for life as we know it. If we also assume that the goal of our life is propagation, then it is reasonable to think that we may have come from that planet - that THAT planet found ours, and pushed life onto it (seeded it, say, with a probe carrying everything necessary to evolve here). Based on that assumption, we should then use that planet as the focal point of a sphere in space, whose radius is defined by the distance from there, to our star. Based on the swept area that sphere includes, it would be our obligation to look for habitable planets outside that area, preferably as far from the originating planet as possible, and take our tun at seeding.
I know it's cool and all, but a giant planet in the habitable zone is more important than a rock planet hovering close to its star's burning atmosphere. Imagine a Saturn + Titan in the habitable zone. We'd only see the Saturn from here, but we can assume that such a planet might have large moons, moons capable of sustaining a dense atmosphere (which I know isn't the most common thing, but still).
Let's imagine a Titan around whichever giant exoplanet we know that's in the habitable zone, and that it has the same amount of biological activity as the Earth does now, what would it take for us to see it spectrally? Actually, what would it take for us to see oscillation in the spectrum of a planet's light (which I suppose isn't easy to separate from its star's light to begin with) that would occur when one of its satellites would be occulted or would occult the planet? (thus allowing us to detect the satellite and learn about its chemical composition). I imagine it's currently out of reach, but that's still an interesting question.
You just got troll'd!
It would be nice if news submissions to *science*.slashdot.org contained hard data URLs, rather than simply paraphrasing other press releases. I would like for example to know precisely *what* us being measured and how it is being measured (brightness vs. radial velocity, spectroscopic planet "light" frequency shifts, etc.). If you only know the orbital period and a radial velocity shift then it would be complete "fiction" (or "certitude" based on dead universe physics). With only a couple of parameters (the star type/age isn't even specified) it is entirely speculation to label an "object" a "planet" rather than say something like a Jupiter Brain.
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