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arcsec

arcsec

9.9
An angle that has a given secant value
  • noun
  • /ˈɑrkˌsɛk/
  • Specialized
translation icon : arcosecante
  • PHOTO (COLOR): The central 1.5 arcsec x 1.5 arcsec of the Milky Way Galaxy.
  • resolution of arcsec
  • about arcsec

Examples

  • The image has a full-width, half-maximum resolution of 0.15 arcsec after deconvolution, which further enhances its quality.

    Academic text (1994)
  • The field of view is 12.8 x 12.8 arcsec, corresponding to about 10 x 10 light years.

    Academic text (1994)
  • Pitch, roll, and yaw errors are to <1/2 arcsec.

    Academic text (1996)
  • PHOTO (COLOR): The central 1.5 arcsec x 1.5 arcsec of the Milky Way Galaxy.

    Academic text (2004)
  • Because the mean height of the turbulence is about 10 km, the guide star and target must therefore be within about 20 cm/10 km = 20 μrad = 4 arcsec.

    Academic text (1994)
  • Field of view is 41 x 41 arcsec, and spatial resolution is 0.4 arcsec. (Image provided by R. Q. Fugate, Phillips Laboratory, and P. McCullough, University of Illinois.)

    Academic text (1994)
  • Field of view is 41 x 41 arcsec, and spatial resolution is 0.4 arcsec. (Image provided by R. Q. Fugate, Phillips Laboratory, and P. McCullough, University of Illinois.)

    Academic text (1994)
  • To operate an adaptive optics system on a telescope at visual wavelengths, a tenth-magnitude (or brighter) reference source must be located within 1 to 2 arcsec of the astronomical target.

    Academic text (1994)
  • The telescope can resolve details as small as 0.15 arcsec in the night sky.

  • The observed shift of 1 arcsec indicated the presence of a new planet.

Synonyms

arcsecant
vsarcsec
  • Specialized
9.9

The angle whose secant is a given number

is the shorter symbolic form used as an abbreviation
arc secant
vsarcsec
  • Specialized
9.9

An angle whose secant or 1 divided by its cosine equals a given number

is the compact symbolic form used instead of the phrase
inverse secant
vsarcsec
  • Specialized
9.9

An angle whose cosine equals 1 divided by a given number

is the concise symbolic form rather than a descriptive phrase

Surface Forms

arcsec singular
arcsecs plural

Morphology

arcsec = arc + secant (transparent) = arc + sec

Formed as a technical compound 'arc' + 'secant' (with 'secant' clipped to 'sec'); the meaning as the arc/angle corresponding to the secant value is directly compositional in mathematical terminology.

Etymology

The word arcsec combines arc ('a part of a circle' or 'an angle') and secant, from Latin secare meaning 'to cut'. A secant was named because it 'cuts' a circle, and arcsec gives the 'arc' or angle that matches a given secant, so it is the angle whose secant is a given number.