Space distance converter
Convert light-years to parsecs, astronomical units and kilometers, and see how long light takes to cross the gap.
That's 383× as far as Voyager 1, while Proxima Centauri is 4.2× further. Light takes about 1 years to cross it.
What it means
How far is that?
One astronomical unit is defined as exactly 149,597,870,700 m, and a light-year uses the Julian year of 365.25 days.
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Three things worth knowing
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A parsec is 3.26 light-years
Proxima Centauri is 4.24 light-years away, or 1.30 parsecs. The parsec is bigger, despite sounding smaller.
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Parallax of one second
A parsec is the distance at which Earth’s orbit spans one arcsecond of sky. It comes straight from how astronomers actually measure distance, by watching stars shift as Earth moves.
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A light-year is a distance
It measures how far light travels in a year, not how long anything takes. Saying something happened "light-years ago" is a category error.
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Background
About astronomical distances
Inside the solar system, distances are counted in astronomical units: the Earth–Sun distance. Beyond it, astronomers use light-years in public writing and parsecs in papers, because a parsec falls straight out of the measurement method.