lightcurve
UK[ˈlaɪtˌkɜːv]US[ˈlaɪtˌkɜːrv]
n
A graph showing the variation in brightness of a celestial object over time.
Morpheme Breakdown
light
curve
light
radiant energy
curve
bent line
Etymology
The term 'lightcurve' is a modern scientific compound, formed in the 20th century within the field of astronomy. It logically combines 'light', referring to the electromagnetic radiation emitted or reflected by a star, planet, or asteroid, with 'curve', denoting the graphical plot of data points. The word's formation follows a transparent English pattern where two independent nouns are joined to create a new, specific concept. The literal meaning, "a curve of light," directly and precisely describes the graphical representation of an object's brightness fluctuations, which astronomers analyze to determine properties like rotation period, shape, or the presence of orbiting companions.
Analysis
Structure: light (radiant energy) + curve (bent line)
- light: From Old English 'lēoht', meaning "brightness, radiant energy". Its Proto-Indo-European root leuk- means "light, brightness".
- curve: From Latin 'curvus', meaning "bent, curved". Its Proto-Indo-European root (s)ker- means "to bend, turn".
Examples
The asteroid's unusual lightcurve suggested it might have a highly elongated shape.
By studying the exoplanet's lightcurve during a transit, scientists can estimate its size.
The variable star's lightcurve shows regular dips in brightness every ten days.