parsecn.

Brit.

/ˈpɑːsɛk/, U.S.

/ˈpɑrˌsɛk/

Origin: Formed within English, by compounding. Etymons: parallax n., second n.¹

Etymology: < par- (in parallax n.) + sec- (in second n.¹) (see quot. 1913).

Astronomy.

A unit of length equal to the distance at which a star would have a heliocentric parallax of one second of arc, approximately equivalent to 3·086 × 10¹³ kilometres (19·2 × 10¹² miles, 3·26 light years).

ΘΚΠ

the world > the universe > cosmology > science of observation > astronomical calculation > [noun] > unit

hour1777

astronomical unit1848

gravitational system1888

au1910

parsec1913

1913 F. W. Dyson in Monthly Notices Royal Astron. Soc. 73 342 There is need for a name for this unit of distance... Professor [H. H.] Turner suggests Parsec, which may be taken as an abbreviated form of ‘a distance corresponding to a parallax of one second’.

1955 Sci. News Let. 29 Jan. 71/2 These hydrogen clouds have diameters of several parsecs, one parsec being the distance light travels in 3·26 years.

1974 S. V. M. Clube in R. H. Stoy Everyman's Astron. viii. 309 The nearest star clusters are the Pleiades and Hyades which are at distances of 130 and 40 parsecs respectively.

1995 D. M. Flinn Fearful Summons 153 The artificial city floated in stationary orbit several parsecs from the Beta Prometheus star system.

This entry has been updated (OED Third Edition, June 2005; most recently modified version published online March 2022).

单词	parsec
释义	parsecn. Brit. /ˈpɑːsɛk/, U.S. /ˈpɑrˌsɛk/ Origin: Formed within English, by compounding. Etymons: parallax n., second n.¹ Etymology: < par- (in parallax n.) + sec- (in second n.¹) (see quot. 1913). Astronomy. A unit of length equal to the distance at which a star would have a heliocentric parallax of one second of arc, approximately equivalent to 3·086 × 10¹³ kilometres (19·2 × 10¹² miles, 3·26 light years). ΘΚΠ the world > the universe > cosmology > science of observation > astronomical calculation > [noun] > unit hour1777 astronomical unit1848 gravitational system1888 au1910 parsec1913 1913 F. W. Dyson in Monthly Notices Royal Astron. Soc. 73 342 There is need for a name for this unit of distance... Professor [H. H.] Turner suggests Parsec, which may be taken as an abbreviated form of ‘a distance corresponding to a parallax of one second’. 1955 Sci. News Let. 29 Jan. 71/2 These hydrogen clouds have diameters of several parsecs, one parsec being the distance light travels in 3·26 years. 1974 S. V. M. Clube in R. H. Stoy Everyman's Astron. viii. 309 The nearest star clusters are the Pleiades and Hyades which are at distances of 130 and 40 parsecs respectively. 1995 D. M. Flinn Fearful Summons 153 The artificial city floated in stationary orbit several parsecs from the Beta Prometheus star system. This entry has been updated (OED Third Edition, June 2005; most recently modified version published online March 2022). < n.1913
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