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| Kepler-22b |
Kepler-22b, a probable extrasolar habitat was found to orbit around the G-type star Kepler-22.It is 600 light years away from our home Earth.The discovery of this planet was confirmed by the Kepler spacecraft.This was the first habitable alien planet confirmed by Kepler. Along with Kepler 22-b 100 more new exoplanet
candidates were discovered which increased the total haul of the Kepler Space Telescope to 2326 potential planets in its first 16 months of operation. It is hoped that this finding would quadruple the current tally of extra-solar worlds on its confirmation.
Kepler detects alien planets by using the "transit method",i.e., searches for tiny telltale dips in a star's brightness caused when a planet crosses in front of the star from earth's perspective, blocking a fraction of star's light. In its first 13 months of operation, Kepler team announced the finding of 1,235 planet candidates , of which 54 are in the habitable zone and 68 are approximately of earth's size.With the new findings of Kepler of 2,326 candidate planets, the number of habitable alien worlds had increased to 48 and the number of planets roughly-earth-sized has increased to 207 with more planets, 680 in number, falling into the category of Super Earth, which have a size a bit larger than that of Earth. However, only 2
dozens of these planets have been confirmed. The Kepler-22b also falls into the
category of "Super Earth" with a radius 2.4 times more than Earth's.
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| A comparison of solar system and Kepler-22 system. |
liquid state on the planet-a habitable temperature. Currently there is no information available about the shape of the orbit. If the orbit would be highly elliptical, it'd have only a short period of optimum temperature at which life can exist(when it'd come into the habitable zone). The state in which the planet exists is still a mystery as with this size it can be rocky, liquid or gas.If the greenhouse effect operates on Kepler-22b as it operates on Earth, then the average surface temperature on it should be72 degrees Fahrenheit(22 degrees celsius).
But, for now, after observing Kepler-22b orbiting in the habitable zone of its host star Kepler-22, we can only hope that it doesn't has a highly elliptical orbit and orbits in the habitable zone throughout its revolution around its star, until it is confirmed by the scientists. "We're getting closer and closer to discovering the so-called 'Goldilocks planet,'" said Pete Worden, director of NASA's Ames Research
Center in Moffett Field, California on 5th December on this occassion. Indeed, we are getting closer to discovering those 'Goldilocks Planets' and so, on someday humans may also be able to inhabit them.
[via:space.com]
[image credit:NASA/Ames/JPL-Caltech]
ANSHUMAN:
ReplyDeleteIn the context of interstellar comparison by “beings” from another solar system perhaps looking at our Sun, would it not be said that Venus, Mars, and Earth fall within the habitability zone from our star?
The Tycho-2 catalog, the most complete and most accurate obtained at present for nearby stars, was released in 2000 from observations of the Hipparcos satellite. This catalog contains 2,539,913 stars exactly located within 500 light years from the Sun, whose luminosity is equal to or greater than a magnitude of 11.
Of course, there are many among the fainter stars, which has a distance of 500 light-years or less that went undetected by Hipparcos. Also, research of life is not interested in the number of stars, but the number of star systems. Indeed, most stars form systems with 2, 3, 4 or even 5 stars (these are called multiple systems).
To estimate the average number of stars within 600 light years, one could extrapolate the data from the Research Consortium On Nearby Stars that posts the closest stars to our solar system. The main advantage is that even the less luminous objects as brown dwarfs are detectable in the nearby suburb of our Sun system in which the Research Consortium On Nearby Stars compiles its data.
One might argue that the density of stars is changing, but I do not think that this density is changed significantly up to 1000 light years. Indeed, the solar system is in a particular structure of our Galaxy, in which the density of stars varies little, called the Orion Arm or Gould Belt. Its size is estimated at 3000 light years thick for 10,000 light years long. So in a bubble of 600 or 1000 light years, the density of stars is not expected to vary significantly.
On the site of Research Consortium On Nearby Stars reads:
http://www.recons.org/
http://www.recons.org/TOP100.posted.htm
Research Consortium On Nearby Stars made the first Accurate distance measurements for 12 of the 100 nearest systems, and 32 of the 259 total systems within 10 parsecs.
One parsec is 3.26 light-years ~ the distance between the star system is about 5.1 L.Y. Within 600 light years, there are about 1.6 million star systems. Within around 1000 light years ago there are 7.5 million star systems.
I think the estimates of 1.6 and 7.5 million stars within 600 and 1000 L.-Y. respectively, are slightly overestimated, simply because it takes into account the fact that brown dwarfs, which are not really stars, and because these bodies are very faint, cannot contain habitable zone (which is the area where a planet would be destroyed by the tidal gravitational forces).
As a matter of fact, has it been produced a sort of 3D image overview of stars known at the 600 light years / 1000 light years distance around? Do we know what the typical interstellar distance is? Which solar system closest to ours given what is known about the frequency of planets in the star systems? We do not know precisely the position and number of stars within 600 light years around the sun. Yet, Voyager 1 and Voyager 2 are joyously parting out of our soar’s fiercest wind by when? By a time no scientist really knows.
While VOY-1 is OUT of the solar speediest wind and now feeling interstellar pressure & medium, how long before it truly reaches the true interstellar galaxy? Anytime now! Or in 5 years! We know not, yet the estimate is real as VOY-1 is traveling at ~ one AU per year away from the sun.
Notwithstanding our estimate of Keppler22 mass, habitability, inhabitability, and when we will be OUT of sun’s sphere, which are all based on the highest level of “educated guess”, Voyager exploring Interstellar space in our galaxy is ultimately the greatest scientific achievement of mankind in exploring the final frontier.
To answer to the question you asked in the first paragraph, I would like to say that they all fall within the habitability zone without any doubt but for many factors working together, life, at least till now,has not been evidenced in any of those planets, with our Earth as an exception.
ReplyDeleteFor the questions you asked in the 7th/8th paragraph, if possible , I need a more clear explanation.
And on your concluding paragraph I would like to comment that no doubt Voyager exploring the interstellar space in our galaxy is the one of the greatest scientific achievements of mankind, but it can not be said, and I think it'd be rather foolish to say "it is ultimately the greatest scientific achievement of mankind in exploring the final frontier." There are many more achievements to come as science has undefined borders of achievements. Moreover, exploring the final frontier doesn't only mean to send a vehicle or spacecraft to explore it as the scientists can also find the activities going on the borders through telescopes and that is how they are exploring far distant Universe.