Kepler-421b

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Kepler-421b
Discovery
Discovery site Kepler telescope
Discovery date2014
Transit
Orbital characteristics
1.219 AU (182,400,000 km)
704.1984 d
Inclination 89.965
Star Kepler-421
Physical characteristics
Mean radius
4.16 R🜨

    Kepler-421b is an exoplanet that, as of July 2014, [1] has the longest known year of any transiting planet (704 days), [2] although not as long as the planets that have been directly imaged, or many of the planets found by the radial-velocity method, or as long as some transiting planet candidates which are listed as planets in the Extrasolar Planets Encyclopaedia (KIC 5010054 b etc.). [3] It is the first transiting-planet found near the snow-line.

    Normally, at least three transits are required to confirm a planet. Due to very high signal to noise ratio, only two transits were sufficient to validate Kepler-421b to be a real planet without additional confirmation methods.

    Kepler-421b is slightly larger than Uranus although its mass is not known.

    Related Research Articles

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    <span class="mw-page-title-main">Kepler-37b</span> Sub-Earth orbiting Kepler-37

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    <span class="mw-page-title-main">Kepler-26</span> Star in the constellation Lyra

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    <span class="mw-page-title-main">Kepler-27</span> G-type star in the constellation Cygnus

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    <span class="mw-page-title-main">Kepler-438b</span> Super-Earth orbiting Kepler-438

    Kepler-438b is a confirmed near-Earth-sized exoplanet. It is likely rocky. It orbits on the inner edge of the habitable zone of a red dwarf, Kepler-438, about 472.9 light-years from Earth in the constellation Lyra. It receives 1.4 times our solar flux. The planet was discovered by NASA's Kepler spacecraft using the transit method, in which the dimming effect that a planet causes as it crosses in front of its star is measured. NASA announced the confirmation of the exoplanet on 6 January 2015.

    <span class="mw-page-title-main">Kepler-442b</span> Super-Earth orbiting Kepler-442

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    Kepler-440b is a confirmed super-Earth exoplanet orbiting within the habitable zone of Kepler-440, about 850 light-years (261 pc) from Earth. The planet was discovered by NASA's Kepler spacecraft using the transit method, in which the dimming effect that a planet causes as it crosses in front of its star is measured. NASA announced the confirmation of the exoplanet on 6 January 2015.

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    Kepler-442 is a K-type main-sequence star approximately 1,206 light years from Earth in the constellation Lyra. It is located within the field of vision of the Kepler spacecraft, the satellite that NASA's Kepler Mission used to detect planets that may be transiting their stars. On January 6, 2015, along with the notable stars of Kepler-438 and Kepler-440, it was announced that the star has an extrasolar planet orbiting within the habitable zone, named Kepler-442b.

    Kepler-1652b is a super-Earth exoplanet, orbiting within the habitable zone of the red dwarf Kepler-1652 about 822 light-years away in the Cygnus constellation. Discovered by NASA's Kepler spacecraft, Kepler-1652b was first announced as a candidate in 2013, but wasn't validated until four years later in 2017. It is a potential super-Earth with 160% Earth's radius. The planet orbits well within the habitable zone of its system, the region where liquid water can exist on a planet's surface. The planet is an eyeball planet candidate.

    <span class="mw-page-title-main">Kepler-443b</span> Extrasolar planet

    Kepler-443b is an exoplanet about 2,540 light-years from Earth. It has an 89.9 percent chance of being in the star's habitable zone, yet only a 4.9 percent chance of being rocky.

    Kepler-1544b is a potentially habitable exoplanet announced in 2016 and located 1138 light years away, in the constellation of Cygnus.

    References

    1. Kipping, D. M.; Torres, G.; Buchhave, L. A.; Kenyon, S. J.; Henze, C.; Isaacson, H.; Kolbl, R.; Marcy, G. W.; Bryson, S. T.; Stassun, K.; Bastien, F. (2014), "Discovery of a Transiting Planet Near the Snow-Line", The Astrophysical Journal, 795 (1): 25, arXiv: 1407.4807 , Bibcode:2014ApJ...795...25K, doi:10.1088/0004-637X/795/1/25, S2CID   119240746
    2. Johnson, Michele (July 21, 2014). "Astronomers Discover Transiting Exoplanet with Longest Known Year". NASA . Retrieved July 25, 2014.
    3. "The Extrasolar Planet Encyclopaedia — Catalog Listing". Extrasolar Planets Encyclopaedia .

    Further reading