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Kepler-186f: Most 'Earth-Like' Alien World Discovered
astroengine (1577233) writes "About 500 light-years away in the constellation Cygnus lives a star, which, though smaller and redder than the sun, has a planet that may look awfully familiar. With a diameter just 10 percent bigger than Earth's, the newly found world is the first of its size found basking in the benign temperature region around a parent star where water, if it exists, could pool in liquid form (abstract). Scientists on the hunt for Earth's twin are focused on worlds that could support liquid surface water, which may be necessary to brew the chemistry of life. "Kepler-186f is significant because it is the first exoplanet that is the same temperature and the same size (well, ALMOST!) as the Earth," David Charbonneau, with the Harvard-Smithsonian Center for Astrophysics, wrote in an email to Discovery News. "Previously, the exoplanet most like Earth was Kepler-62f, but Kepler-186f is significantly smaller. Now we can point to a star and say, 'There lies an Earth-like planet.'""
If I do, I could be there in what, 25k years..round about?
After all, Mericans are always saying to me "if ya don't like it, git'out".
Well?
If we are quiet, maybe we'll get lucky and they won't notice us....
I am very small, utmostly microscopic.
Because the future of humanity depends on getting off of this rock eventually.
Wrong! Think of all the cheap labor we could exploit by conquering the natives!
Mod me down, my New Earth Global Warmingist friends!
No, it would be OK to send a generation ship, where people live their lifespans on board raising their children. Assuming we could build something that lasts long enough without a BSOD.
If they are advanced enough to travel here then they've had their own version of the Kepler telescope for 500 years and have known at the minimum that Earth has liquid water, oxygen, and chlorophyll (I think that can be picked up used spectroscopy). Basically anyone advanced civilization nearby probably has known about Earth as a life-bearning world long before humans came along.
Just a cool thought to counter the idea that we're hidden until someone detects radio.
I believe this planet will be like Venus, a rocky surface, but a CO2 atmosphere that makes it at least 300 degrees Celsius on the surface.
I worked out this whole interstellar travel problem years ago. Also solves the problem of the negative effects of zero gee in space.
All you need is to have your ship accelerate at a constant rate of one gee, do that for half the trip, then turn the ship around and decelerate at the same speed until you get to your final destination.
The acceleration solves all your artificial gravity woes, and relativity solves all your lifespan worries--by my calculations, a trip to anywhere in the universe using this method would only take about two years for the passenger.
Of course, you need a way to fuel a ship that's accelerating/decelerating at one gee for two years, but that's just an engineering problem.
Earth-like depends on context. For me... if it has free wifi, it qualifies.
How much of this "habitable zone" factors in water's ability to be liquid to to pressure? Too thin it vaporizes (Mars). Too much, it vaporizes (Venus). Merely being the right temperature isn't enough.
Also, having a magnetic pole strong enough to shield it from the solar wind, so what does wind up in the atmosphere doesn't wind up in space.
Slashdot's rate-of-post filter: Preventing you from posting too many great ideas at once.
Actually, at near light speed, time slows down, so a person who embarks on a journey in a spaceship capable of moving near enough to the speed of light could conceivably reach a destination many hundreds or even thousands of light years away in their own lifetime.
Of course, everyone that they left behind and ever knew will be long gone.
File under 'M' for 'Manic ranting'
An engineering problem in the sense that there is not enough matter in the universe to accelerate a spacecraft at 1 g for 2 years using any currently plausible propulsion method.
>The sooner we launch one, the sooner our descendants get to hear back from it.
Not necessarily. Or more precisely by the time they hear back from it the information will likely be completely redundant.
At present all our mature propulsion technology is very much focused on planetary usage. Rocketry is the only one at all suitable to operating in space, and it's *horribly* inefficient in terms of specific impulse, which will be *the* deciding factor for interstellar travel. Ion drives show immense promise, already completely trouncing chemical rocketry in terms of specific impulse, but it's a technology very much in its infancy and the absolute thrust current engines can produce is miniscule, useful for little more than station-keeping and lining up gravitational slingshot maneuvers. If we launched an interstellar probe with today's technology then it's quite likely that a second probe launched 50-100 years from now would be able to make several round trips before today's probe ever got anywhere close to the target. For a mission whose expected payoff is centuries away that sort of thing is well worth considering. Much like Voyager making its pokey way out of the solar system, the value of an interstellar probe built on current-gen technology would be primarily in learning about the beginning of the path, not the destination. And unless there's some completely unexpected navigation hazard in the gulf between stars there's unlikely to be much to learn worth the cost of the probe.
Now what might be an interesting mission with current or near-term technology is a gravitational-lens telescope - rather than sending a probe towards Kepler-186f we send a telescope "eyepiece" in the opposite direction, and when it reaches a distance of only about 700AU (0.011 light years, ~10x Voyager 1's current distance) away from the sun we could start to use the sun's gravitational field as an immense lens in a telescope so powerful we could count the pebbles on 186f's hypothetical beaches. Maybe even individual grains of sand. Not to mention everything else we might see in that general direction. The downside to such a telescope is that it's extremely difficult to substantially change the target. With a telescope 700AU long even a few degrees of change requires moving your eyepiece across a distance rivaling Pluto's orbit. Still, with a clever flight plan we could get immensely detail information about dozens or hundreds of other star systems as our eyepiece slowly swept out a few degrees of motion. The only real question is, is 186f really interesting enough to be the first target? I would imagine looking toward the galactic core would offer far more interesting things to see.
--- Most topics have many sides worth arguing, allow me to take one opposite you.
Interesting fact: at ~0.7c, the kinetic energy is equal to the rest mass of the ship. So if you have a photon drive running off of a perfectly efficient total conversion engine, you'll have fed more than half your ship to the converter by then.
The solution would be not to have the power source on the ship.