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light-year
(lt-yr, ly)
subjectfact 
light-yearhas symbol lt-yr2001-09-27 09:32:47.0
has symbol ly2001-09-27 09:32:47.0
has definition Distance traveled at the speed of light for one Earth-year: 9.46 million million km.has source: Abbot, D. 1984 Astronomers, Peter Bedrick Books, New York, 2001-09-27 09:32:46.0
has definition The distance light travels in one year: 5.88 trillion miles, or 9.46 trillion kilometers. The nearest star system to the Sun is 4.3 light-years away.has source: Croswell, K. 1995 The Alchemy of the Heavens, Anchor Books, 2001-09-27 09:32:46.0
has definition The distance light travels in one year, equal to 5.8 × 1012 (about six trillion) miles.has source: Ferris, T. 1988 Coming of Age in the Milky Way, Morrow, 2001-09-27 09:32:47.0
has definition The distance traveled in a vacuum by light in one year, equal to 9.46 × 1017cm.has source: Silk, J. 1990 The Big Bang, W. H. Publishers, New York, 2001-09-27 09:32:47.0
has definition The distance that light traverses in a vacuum during one year.has source: Seidelman, P. 1992 Explanatory Supplement to the Astronomical Almanac, University Science Books, Mill Valley, CA, 2001-09-27 09:32:47.0
has definition The distance light travels in a vacuum in 1 year. 1 lt-yr = 9.4605 × 1012 km = 0.307 pc (c = 299792.46 km s-1 = 186274 miles s-1). (1 lt-min ≈ 0.13 AU.)has source: Hopkins, J. 1976 Glossary of Astronomy and Astrophysics, University of Chicago Press, 2001-09-27 09:32:47.0
is an instance of length unit2001-09-27 09:32:46.0
length unitis a unit of length2001-09-27 09:32:45.0
unithas historical origin2001-09-27 09:32:42.0
represents2001-09-27 09:32:42.0