light-day n.

the distance light travels in 24 hours

  • 1933 J. L. Burtt When the Universe Shrank in Amazing Stories Nov. 103/1 page image J. Lewis Burtt bibliography

    These were spread out over the area of a circle of nearly one light-day in diameter.

  • 1943 A. E. van Vogt Concealment in Astounding Science-Fiction Sept. 93/2 page image A. E. van Vogt bibliography

    If you wish, I will prepare orbits involving maximum speeds of ten light days a minute to all the nearest stars.

  • 1949 R. Abernathy Giants Return in Planet Stories Fall 45/2 page image Robert Abernathy bibliography

    One light-day out from Procyon, the thirty-third day by ship’s time since leaving Earth.

  • 1956 R. F. Jones Academy for Pioneers in Astounding Science Fiction May 94/2 Raymond F. Jones bibliography

    It was an insignificant run to the region of Proteus VI. The hyper-drive of the Paracelsus made the two light-day trip in a matter of subjective micro-seconds, but even so the shift required the usual preparations of banking down all electro-magnetic equipment of any kind.

  • 1971 G. Benford & D. Franson Star Crossing in Worlds of If Mar. 88/2 page image Gregory Benford Donald Franson bibliography

    They can’t use gravity waves, so they have to signal by radio or light and they were about two light-days out then.

  • 1981 S. T. Possony & J. Pournelle Space & the Longevity of Man in Isaac Asimov’s Science Fiction Magazine 13 Apr. 122 page image Jerry Pournelle Stefan T. Possony bibliography

    There might be many civilizations ‘close’ together—a few light days from each other.

  • 1999 M. J. Friedman My Brother’s Keeper i. i. 4 Michael Jan Friedman bibliography

    There’s a planet a few light-days away from here.

  • 2012 L. Niven & E. M. Lerner Fate of Worlds viii. 68 page image Larry Niven Edward M. Lerner bibliography

    A very thin line encircled the bridge: short navy-blue dashes alternating with longer pale blue dashes. The Ringworld. Or, rather, Endurance having exited hyperspace sixty light-days from its destination, the Ringworld as it had appeared sixty days earlier.

Research requirements

antedating 1933

Earliest cite

J. Lewis Burtt, "When the Universe Shrank"

Research History
Malcolm Farmer submitted a 1956 cite from Raymond F. Jones' "Academy For Pioneers".
Fred Galvin submitted a 1949 cite from Robert Abernathy's "The Giants Return".
Fred Galvin submitted a cite from a 1970 reprint of A.E. Van Vogt's "Concealment", which Mike Christie verified in its original 1943 publication.
Bill Mullins submitted a cite from J. Lewis Burtt's "When the Universe Shrank".
Ben Ostrowsky submitted a 2012 cite from Niven & Lerner's "Fate of Worlds".

Earliest cite in the OED: 1963

Last modified 2021-10-18 22:56:17
In the compilation of some entries, HDSF has drawn extensively on corresponding entries in OED.