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koi

n. countable
C2 Proficiency koi

n. Stands for Kepler Object of Interest. A star that a space telescope has looked at because it might have a planet moving around it. Scientists study these to see if the planet is real or just a mistake in the data.

n. Abbreviation for Kepler Object of Interest. A star observed by the Kepler mission that exhibits periodic dimming, suggesting the presence of a transiting exoplanet candidate. These targets require further spectroscopic or photometric validation to confirm their planetary status.


SIMPLE

The team found a new koi that might be an Earth-like planet.

CONTEXTUAL

After analyzing the light curves from the telescope, the researchers identified a promising koi in the Cygnus constellation.

COMPLEX

While thousands of stars were flagged as a koi during the initial mission, many were later reclassified as false positives caused by eclipsing binary star systems rather than orbiting planets.

Origin

From Japanese 鯉 (koi).

Usage

Often written in all-caps as KOI; typically followed by a catalog number in scientific papers.

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