Kepler-186b
{{Short description|Terrestrial exoplanet orbiting Kepler-186}}{{Notability|Astro|date=May 2025}}{{Infobox planet
| name = Kepler-186b
| discoverer = Jason F. Rowe et al.
| discovery_site = Kepler Space Observatory
| discovered = 26 February 2014
| discovery_method = Transit
| apsis = astron
| semimajor = 0.0343 (± 0.0046){{cite web|url=http://exoplanetarchive.ipac.caltech.edu/cgi-bin/DisplayOverview/nph-DisplayOverview?objname=Kepler-186+b|title=Kepler-186 b|work=NASA Exoplanet Archive|accessdate=29 December 2016}} AU
| period = 3.8867907 d
0.010641 y
| inclination = 83.56
| star = Kepler-186
| mean_radius = 1.07 (± 0.12) {{Earth radius|link=y}}
| single_temperature = Teq: {{convert|666|K|C F}}
}}
Kepler-186b (also known as KOI-571.03) is an exoplanet located around 582 light-years away from Earth. Kepler-186b orbits a red dwarf known as Kepler-186, named after the space telescope that found it.{{cite encyclopedia | url=https://exoplanet.eu/catalog/kepler_186_b--1615/ | encyclopedia=Extrasolar Planets Encyclopaedia | title=The Extrasolar Planet Encyclopaedia — Kepler-186 B | date=2018 }}{{Better source needed|reason=The current source is insufficiently reliable (WP:NOTRS).|date=May 2025}}
Physical characteristics
= Orbit =
Kepler-186b is the innermost planet and the smallest of its system, and thus not suitable for life. The orbital period of this planet is just under four Earth 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 within the habitable zone.
References
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Category:Transiting exoplanets
Category:Exoplanets discovered in 2014
{{Kepler-186}}{{Cygnus (constellation)}}
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