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Kepler-186
Kepler-186 is a main-sequence M1-type dwarf star, located 178.5 parsecs (582 light years) away in the constellation of Cygnus. The star is slightly cooler than the sun, with roughly half its metallicity. It is known to have five planets, including the first Earth-sized world discovered in the habitable zone: Kepler-186f. free version = http://www.nasa.gov/sites/default/files/files/kepler186_main_final.pdf The star hosts four other planets discovered so far, though they all orbit interior to the habitable zone. Star A number of previously unknown measurements of the star are known.VizieR Detailed Page for 2MASS 19543665+4357180, "This publication makes use of data products from the Two Micron All Sky Survey, which is a joint proj ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kepler-186f
Kepler-186f (also known by its Kepler object of interest designation KOI-571.05) is an exoplanet orbiting the red dwarf Kepler-186, about from Earth. It was the first planet with a radius similar to Earth's to be discovered in the habitable zone of another star. NASA's Kepler space telescope detected it using the transit method, along with four additional planets orbiting much closer to the star (all modestly larger than Earth). Analysis of three years of data was required to find its signal. The results were presented initially at a conference on 19 March 2014 See session 19 March 2014 – Wednesday 11:50–12:10 – Thomas Barclay: The first Earth-sized habitable zone exoplanets. and some details were reported in the media at the time. The public announcement was on 17 April 2014, followed by publication in ''Science''. Physical characteristics Mass, radius and temperature The only physical property directly derivable from the observations (besides orbit) is the size o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kepler-186
Kepler-186 is a main-sequence M1-type dwarf star, located 178.5 parsecs (582 light years) away in the constellation of Cygnus. The star is slightly cooler than the sun, with roughly half its metallicity. It is known to have five planets, including the first Earth-sized world discovered in the habitable zone: Kepler-186f. free version = http://www.nasa.gov/sites/default/files/files/kepler186_main_final.pdf The star hosts four other planets discovered so far, though they all orbit interior to the habitable zone. Star A number of previously unknown measurements of the star are known.VizieR Detailed Page for 2MASS 19543665+4357180, "This publication makes use of data products from the Two Micron All Sky Survey, which is a joint proj ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kepler-186d
Kepler-186 is a main-sequence M1-type dwarf star, located 178.5 parsecs (582 light years) away in the constellation of Cygnus. The star is slightly cooler than the sun, with roughly half its metallicity. It is known to have five planets, including the first Earth-sized world discovered in the habitable zone: Kepler-186f. free version = http://www.nasa.gov/sites/default/files/files/kepler186_main_final.pdf The star hosts four other planets discovered so far, though they all orbit interior to the habitable zone. Star A number of previously unknown measurements of the star are known.VizieR Detailed Page for 2MASS 19543665+4357180, "This publication makes use of data products from the Two Micron All Sky Survey, which is a joint proj ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kepler-186c
Kepler-186 is a main-sequence M1-type dwarf star, located 178.5 parsecs (582 light years) away in the constellation of Cygnus. The star is slightly cooler than the sun, with roughly half its metallicity. It is known to have five planets, including the first Earth-sized world discovered in the habitable zone: Kepler-186f. free version = http://www.nasa.gov/sites/default/files/files/kepler186_main_final.pdf The star hosts four other planets discovered so far, though they all orbit interior to the habitable zone. Star A number of previously unknown measurements of the star are known.VizieR Detailed Page for 2MASS 19543665+4357180, "This publication makes use of data products from the Two Micron All Sky Survey, which is a joint proj ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kepler-186e
Kepler-186e (also known by its Kepler Object of Interest designation ''KOI-571.04'') is a confirmed exoplanet orbiting the red dwarf star Kepler-186, approximately 582 light years away from Earth in the constellation of Cygnus. It is near the optimistic habitable zone but probably not in it, possibly making it have a runaway greenhouse effect, like Venus. The exoplanet was found by using the transit method, in which the dimming effect that a planet causes as it crosses in front of its star is measured. Four additional planets orbiting the star (all modestly larger than Earth) were also discovered. Physical characteristics Mass, orbit, and composition The exoplanet is only slightly larger than Earth, with a radius 1.27–1.33 times that of Earth. Its mass is not known but it is likely to have a similar composition to Earth, giving it a mass of about 2.29–2.72 times the mass of the Earth. Kepler-186e orbits an M-dwarf star with about 4% of the Sun's luminosity with an orbital p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kepler-186b
Kepler 186b (also known as KOI-571.03) is an exoplanet located around 582 light-years away from Earth. Kepler-186b is orbiting a red dwarf known as Kepler-186, named after the space telescope A space telescope or space observatory is a telescope in outer space used to observe astronomical objects. Suggested by Lyman Spitzer in 1946, the first operational telescopes were the American Orbiting Astronomical Observatory, OAO-2 launched ... that found it. Kepler-186b is the innermost planet of its system, and thus not suitable for life. One year on the planet is only 3.884 days long due to its location near the parent star. It is tidally locked. As a result, one hemisphere is in eternal daylight while the other hemisphere is in endless darkness. The other planets in the system are Kepler-186c, d, e, and f, of which only Kepler-186f is habitable. References Transiting exoplanets Exoplanets discovered in 2014 Kepler-186 186b {{exoplanet-stub Cygnus (constellation) [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Circumstellar Habitable Zone
In astronomy and astrobiology, the circumstellar habitable zone (CHZ), or simply the habitable zone, is the range of orbits around a star within which a planetary surface can support liquid water given sufficient atmospheric pressure.J. F. Kasting, D. P. Whitmire, R. T. Reynolds, Icarus 101, 108 (1993). The bounds of the CHZ are based on Earth's position in the Solar System and the amount of radiant energy it receives from the Sun. Due to the importance of liquid water to Earth's biosphere, the nature of the CHZ and the objects within it may be instrumental in determining the scope and distribution of planets capable of supporting Earth-like extraterrestrial life and intelligence. The habitable zone is also called the Goldilocks zone, a metaphor, allusion and antonomasia of the children's fairy tale of " Goldilocks and the Three Bears", in which a little girl chooses from sets of three items, ignoring the ones that are too extreme (large or small, hot or cold, etc.), and set ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Exoplanet
An exoplanet or extrasolar planet is a planet outside the Solar System. The first possible evidence of an exoplanet was noted in 1917 but was not recognized as such. The first confirmation of detection occurred in 1992. A different planet, initially detected in 1988, was confirmed in 2003. There are many methods of detecting exoplanets. Transit photometry and Doppler spectroscopy have found the most, but these methods suffer from a clear observational bias favoring the detection of planets near the star; thus, 85% of the exoplanets detected are inside the tidal locking zone. In several cases, multiple planets have been observed around a star. About 1 in 5 Sun-like starsFor the purpose of this 1 in 5 statistic, "Sun-like" means G-type star. Data for Sun-like stars was not available so this statistic is an extrapolation from data about K-type stars. have an "Earth-sized"For the purpose of this 1 in 5 statistic, Earth-sized means 1–2 Earth radii. planet in the habitable zone. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metallicity
In astronomy, metallicity is the abundance of elements present in an object that are heavier than hydrogen and helium. Most of the normal physical matter in the Universe is either hydrogen or helium, and astronomers use the word ''"metals"'' as a convenient short term for ''"all elements except hydrogen and helium"''. This word-use is distinct from the conventional chemical or physical definition of a metal as an electrically conducting solid. Stars and nebulae with relatively high abundances of heavier elements are called "metal-rich" in astrophysical terms, even though many of those elements are nonmetals in chemistry. The presence of heavier elements hails from stellar nucleosynthesis, where the majority of elements heavier than hydrogen and helium in the Universe (''metals'', hereafter) are formed in the cores of stars as they evolve. Over time, stellar winds and supernovae deposit the metals into the surrounding environment, enriching the interstellar medium and providing ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Space
Space is the boundless three-dimensional extent in which objects and events have relative position and direction. In classical physics, physical space is often conceived in three linear dimensions, although modern physicists usually consider it, with time, to be part of a boundless four-dimensional continuum known as spacetime. The concept of space is considered to be of fundamental importance to an understanding of the physical universe. However, disagreement continues between philosophers over whether it is itself an entity, a relationship between entities, or part of a conceptual framework. Debates concerning the nature, essence and the mode of existence of space date back to antiquity; namely, to treatises like the ''Timaeus'' of Plato, or Socrates in his reflections on what the Greeks called ''khôra'' (i.e. "space"), or in the ''Physics'' of Aristotle (Book IV, Delta) in the definition of ''topos'' (i.e. place), or in the later "geometrical conception of place" as "spac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tidal Force
The tidal force is a gravitational effect that stretches a body along the line towards the center of mass of another body due to a gradient (difference in strength) in gravitational field from the other body; it is responsible for diverse phenomena, including tides, tidal locking, breaking apart of celestial bodies and formation of ring systems within the Roche limit, and in extreme cases, spaghettification of objects. It arises because the gravitational field exerted on one body by another is not constant across its parts: the nearest side is attracted more strongly than the farthest side. It is this difference that causes a body to get stretched. Thus, the tidal force is also known as the differential force, as well as a secondary effect of the gravitational field. In celestial mechanics, the expression ''tidal force'' can refer to a situation in which a body or material (for example, tidal water) is mainly under the gravitational influence of a second body (for example, the Eart ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tidally Locked
Tidal locking between a pair of co-orbiting astronomical body, astronomical bodies occurs when one of the objects reaches a state where there is no longer any net change in its rotation rate over the course of a complete orbit. In the case where a tidally locked body possesses synchronous rotation, the object takes just as long to Rotation around a fixed axis, rotate around its own axis as it does to revolve around its partner. For example, the same side of the Moon always faces the Earth, although there is some libration, variability because the Moon's orbit is not perfectly circular. Usually, only the natural satellite, satellite is tidally locked to the larger body. However, if both the difference in mass between the two bodies and the distance between them are relatively small, each may be tidally locked to the other; this is the case for Pluto and Charon (moon), Charon. Alternative names for the tidal locking process are gravitational locking, captured rotation, and spin–orb ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
