Skip to comments.First Potentially Habitable Earth-Sized Planet Confirmed By Gemini And Keck Observatories
Posted on 07/08/2014 4:08:20 PM PDT by robowombat
First Potentially Habitable Earth-Sized Planet Confirmed By Gemini And Keck Observatories by Staff Writers Hilo HI (SPX) Apr 23, 2014
The artist's concept depicts Kepler-186f, the first validated Earth-size planet orbiting a distant star in the habitable zone-a range of distances from a star where liquid water might pool on the surface of an orbiting planet. The discovery of Kepler-186f confirms that Earth-size planets exist in the habitable zone of other stars and signals a significant step closer to finding a world similar to Earth. The artistic concept of Kepler-186f is the result of scientists and artists collaborating to help imagine the appearance of these distant worlds. Art courtesy Danielle Futselaar. The first Earth-sized exoplanet orbiting within the habitable zone of another star has been confirmed by observations with both the W. M. Keck Observatory and the Gemini Observatory. The initial discovery, made by NASA's Kepler Space Telescope, is one of a handful of smaller planets found by Kepler and verified using large ground-based telescopes. It also confirms that Earth-sized planets do exist in the habitable zone of other stars.
"What makes this finding particularly compelling is that this Earth-sized planet, one of five orbiting this star, which is cooler than the Sun, resides in a temperate region where water could exist in liquid form," says Elisa Quintana of the SETI Institute and NASA Ames Research Center who led the paper published in the current issue of the journal Science.
The region in which this planet orbits its star is called the habitable zone, as it is thought that life would most likely form on planets with liquid water.
Steve Howell, Kepler's Project Scientist and a co-author on the paper, adds that neither Kepler (nor any telescope) is currently able to directly spot an exoplanet of this size and proximity to its host star. "However, what we can do is eliminate essentially all other possibilities so that the validity of these planets is really the only viable option."
With such a small host star, the team employed a technique that eliminated the possibility that either a background star or a stellar companion could be mimicking what Kepler detected. To do this, the team obtained extremely high spatial resolution observations from the eight-meter Gemini North telescope on Mauna Kea in Hawai`i using a technique called speckle imaging, as well as adaptive optics (AO) observations from the ten-meter Keck II telescope, Gemini's neighbor on Mauna Kea.
Together, these data allowed the team to rule out sources close enough to the star's line-of-sight to confound the Kepler evidence, and conclude that Kepler's detected signal has to be from a small planet transiting its host star.
"The Keck and Gemini data are two key pieces of this puzzle," says Quintana. "Without these complementary observations we wouldn't have been able to confirm this Earth-sized planet."
The Gemini "speckle" data directly imaged the system to within about 400 million miles (about 4 AU, approximately equal to the orbit of Jupiter in our solar system) of the host star and confirmed that there were no other stellar size objects orbiting within this radius from the star.
Augmenting this, the Keck AO observations probed a larger region around the star but to fainter limits. According to Quintana, "These Earth-sized planets are extremely hard to detect and confirm, and now that we've found one, we want to search for more. Gemini and Keck will no doubt play a large role in these endeavors."
The host star, Kepler-186, is an M1-type dwarf star relatively close to our solar system, at about 500 light years and is in the constellation of Cygnus. The star is very dim, being over half a million times fainter than the faintest stars we can see with the naked eye.
Five small planets have been found orbiting this star, four of which are in very short-period orbits and are very hot. The planet designated Kepler-186f, however, is earth-sized and orbits within the star's habitable zone.
The Kepler evidence for this planetary system comes from the detection of planetary transits. These transits can be thought of as tiny eclipses of the host star by a planet (or planets) as seen from the Earth. When such planets block part of the star's light, its total brightness diminishes.
Kepler detects that as a variation in the star's total light output and evidence for planets. So far more than 3,800 possible planets have been detected by this technique with Kepler.
The Gemini data utilized the Differential Speckle Survey Instrument (DSSI) on the Gemini North telescope.
DSSI is a visiting instrument developed by a team led by Howell who adds, "DSSI on Gemini Rocks! With this combination, we can probe down into this star system to a distance of about 4 times that between the Earth and the Sun. It's simply remarkable that we can look inside other solar systems."
DSSI works on a principle that utilizes multiple short exposures of an object to capture and remove the noise introduced by atmospheric turbulence producing images with extreme detail.
Observations with the W.M. Keck Observatory used the Natural Guide Star Adaptive Optics system with the NIRC2 camera on the Keck II telescope. NIRC2 (the Near-Infrared Camera, second generation) works in combination with the Keck II adaptive optics system to obtain very sharp images at near-infrared wavelengths, achieving spatial resolutions comparable to or better than those achieved by the Hubble Space Telescope at optical wavelengths.
NIRC2 is probably best known for helping to provide definitive proof of a central massive black hole at the center of our galaxy. Astronomers also use NIRC2 to map surface features of solar system bodies, detect planets orbiting other stars, and study detailed morphology of distant galaxies.
"The observations from Keck and Gemini, combined with other data and numerical calculations, allowed us to be 99.98% confident that Kepler-186f is real," says Thomas Barclay, a Kepler scientist and also a co-author on the paper. "Kepler started this story, and Gemini and Keck helped close it," adds Barclay.
How many box tops does it take to get there?
Hopefully that one isn’t filled with liberals. It would be nice to have our own conservative planet. We could even call it Free Republic.
The planet designated Kepler-186f, however, is earth-sized and orbits within the star’s habitable zone. ................................ Well I guess there isn’t a rush to go buy property there at the moment. I guess when we run out of oil, we’ll have to look for it there. I’m sure we don’t have to rush, its only 500 light years away. I’m sure as the years go by there will be many more livable planets found. At the same time, someone or something out there may be looking at our planet for the same reasons we are looking at theirs.
I’m packing. When does my ride get here?
I’m over 70. They need to perfect cryogenics before I can board the rocket ship.
Will I have to support parasitic scum or be free?
I volunteer! Get me outta here.
Juan Pabla Montoya and Kyle Larson Thank You!
The planet’s atmospheric composition could potentially be determined via a process known as mass spectroscopy if it moved in front of a bright background light source such as the host star.
“The reflected light of a planet contains absorption bands due to minerals in the rocks present for rocky bodies, or due to the elements and molecules present in the atmospheres of gas giants. To date almost 1000 exoplanets have been discovered. These include so-called Hot Jupiters, as well as Earth-like planets. Using spectroscopy, compounds such as alkali metals, water vapor, carbon monoxide, carbon dioxide, and methane have all been discovered.”
“Transmission spectroscopy is a technique used to gather details about the chemical composition and the extent of the atmosphere of a transiting exoplanet. As the light from the host star passes through the atmosphere of the planet, some of the light is absorbed by the atoms, molecules or grains present in the atmosphere, making the exoplanet appear bigger. A plot of the size of the exoplanet as a function of wavelength gives a transmission spectrum. The shape of the transmission spectrum itself then can indicate which components are present in the atmosphere. An example of a transmission spectrum is shown below.
Transmission spectroscopy has been used to extensively to study the atmospheres of HD 209458 b and HD 189733 b amongst many other transiting planets”
In reality we might just leave as a fuel component.
Ridicules comment. Are you suggesting exploration, observation, study and research for earth similar planets, other life, etc be stopped or is somehow nonsense?
Future inhabitants, our species on this little planet have more to worry about than running out of oil, since this planet and our sun have a shelf life which will leave earth a burned charcoal cinder or just vaporized.
Should exploration be given up because with current existing technology, they're too far away to get to or communicate with? I don't think so. There is a whole lot more we don't know than we do know at this point.
Man stays here and eventually man's time ends here. There will be no need for oil, water, history of man or anything else.
um, since it was the scientists themselves saying this, yes, you are spot on as to how honest and forthright they are. good of you to see that.
as for accuracy, the scientist is telling you what today’s technology is capable of.
it’s way better than it was 50 or 100 years ago and will be significantly better 100 years from now.
that’s a good thing, right?
The exact quote is forty-two. As everyone knows, 40-2 = 38.
The deep thought answer to the question is thus 38
Are you suggesting exploration, observation, study and research for earth similar planets, other life, etc be stopped or is somehow nonsense? .................................Nope, just saying it won’t affect us here and now. None of us will be on the first ship there. At the rate our planet is populating, we will need a place to go, unless we produce large amounts of Soylent Green. Who knows how far we can go in another 1,000 years? We may advance or we may be wiped out by a 25,000 mph asteroid within a century. Then again why worry when none of us know what the next day may bring. Light speed is still a thing of science fiction. Sounds like it would be a lot of fun flying through an asteroid belt at that speed.
Nope, just saying it wont affect us here and now.
No one suggested that. Nothing is instant, not even instant coffee.
This should be pretty obvious.
I'm confident it's understood achieving capability of interstellar travel, detecting and identifying planets capable of supporting life, other life forms, communicating across the universe and developing technology other than conventional rocket ships, is going to take a bit of time.
um, yeah, it’s a better guess than 50 or 100 years ago.
Nonsense. Forty twos is 80. Sheesh, learn some math.
um, yeah, its a better guess than 50 or 100 years ago.
Yea, you’re right. Science has gotten us nowhere in the last 100 years.