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light-year
(redirected from Lightyears)

    Also found in: Dictionary/thesaurus, Wikipedia 0.01 sec.
light-year, in astronomy, unit of length equal to the distance light light, visible electromagnetic radiation. Of the entire electromagnetic spectrum, the human eye is sensitive to only a tiny part, the part that is called light. The wavelengths of visible light range from about 350 or 400 nm to about 750 or 800 nm.
..... Click the link for more information.  travels in one sidereal year sidereal year, time required for the earth to complete an orbit of the sun relative to the stars. The sidereal year is 365 days, 6 hr, 9 min, 9.5 sec of mean solar time (see solar time).
..... Click the link for more information. . It is 9.461 × 1012 km (about 6 million million mi). Alpha Centauri Alpha Centauri , brightest star in the constellation Centaurus and 3d-brightest star in the sky; also known as Rigil Kent or Rigil Kentaurus; 1992 position R.A. 14h39.1m, Dec. −60°49'.
..... Click the link for more information.  and Proxima Centauri, the stars nearest our solar system, are about 4.3 light-years distant. See also parsec parsec [parallax + second], in astronomy, basic unit of length for measuring interstellar and intergalactic distances, equal to 206,265 times the distance from the earth to the sun, 3.26 light-years, or 3.
..... Click the link for more information. .

light-year

Distance traveled by light moving in a vacuum in one year, at its accepted speed of 186,282 mi/second (299,792 km/second). It equals about 5.9 trillion mi (9.5 trillion km), 63,240 astronomical units, or 0.307 parsec.

light-year [′līt ‚yir]
(astrophysics)
A unit of measurement of astronomical distance; it is the distance light travels in one sidereal year and is equivalent to 9.461 × 1012kilometers or 5.879 × 1012miles.
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Yet another claims, Eoe1/4EoPresenting lifestyles that are lightyears aheadEoe1/4A[yen].
Top realtors woo property buyers in the Sultanate by Times of Oman (Muscat, Oman)
Makovsky won Berwick's first race then Paul Clews finished behind Mark Lemon in their only heat advantage at 3-5 but the Comets were lightyears ahead of them.
Bandits put Shield hopes on the line; SPEEDWAY by The Journal (Newcastle, England)
If we have a fight he can't beat me at that and skillwise I'm lightyears away.
Truscott: I'll look like a million dollars by Evening Gazette (Middlesbrough, England)
 
 
 
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