Limits RegistryPUBLIC RECORD
Limits RegistryKepler-37b, announced in February 2013 from NASA Kepler data, is only slightly larger than Earth's Moon, with a radius of about 0.3 Earth radii (roughly 1,900 km). It orbits a Sun-like star about 210 light-years away every 13 days. Its radius relied on asteroseismology of the host star, and some later analyses revise the size, so the figure is not fully settled.
The question, scope, and sources behind this Registry record.
Kepler-37b, announced in February 2013 from NASA Kepler data, is only slightly larger than Earth's Moon, with a radius of about 0.3 Earth radii (roughly 1,900 km). It orbits a Sun-like star about 210 light-years away every 13 days. Its radius relied on asteroseismology of the host star, and some later analyses revise the size, so the figure is not fully settled.
The smallest radius measured for any confirmed exoplanet orbiting a normal main-sequence star.
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Current frontiers derived from accepted Claims.
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The frontier as it changed over time.
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1 accepted Claim, with 1 linked evidence records.
Permanent ID limitsregistry.com/limits/LR-SMALLEST-KNOWN-EXOPLANET
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Limits Registry. LR-SMALLEST-KNOWN-EXOPLANET. Smallest known exoplanet around a Sun-like star. 2026.