Where does this come from, and can I check it?

It is the distance at which Earth's orbit subtends one arcsecond. The figure is taken from Britannica, which is linked in full on this page. Every fact on Mondo Knows names its source rather than repeating an unsourced claim.

Is this really a space fact?

Yes. It sits on the Space shelf, one of 2,600 sourced facts grouped into space, animals, the human body, history, science and more. Category pages collect every fact in the same field.

What else can I read about it?

The links under the fact point to a quiz, game, puzzle or calculator on the same subject, and the shelf below shows related facts. The wording here is original, and quoted phrases are marked as quotations.

Mondo Knows Facts

A parsec is a parallax measurement, not a time

It is the distance at which Earth's orbit subtends one arcsecond The name contracts parallax of one arcsecond, and the unit equals about 3.26 light years. Astronomers measure a nearby star's apparent shift against background stars six months apart. The technique only works for stars close enough to show a measurable wobble. It sits in Mondo's space collection, one of 200 facts that each trace back to the reference below.

Where this comes from

Britannica

Facts that can change over time are reviewed and updated. If something here looks wrong, Mondo would rather know than be confidently incorrect.

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Science trivia

More facts like this

A light year is 9.461 trillion kilometresIt measures distance, not time, and the nearest star is over four away A parsec comes from a tiny parallax angleOne arcsecond of apparent shift equals 3.26 light years of distance Splitting starlight reveals what a star is made ofEach element leaves dark lines at fixed wavelengths The observable universe contains septillions of starsAstronomers estimate there are more stars in space than sand grains on Earth Proxima Centauri is the closest star to our solar systemThe red dwarf star sits roughly four point two light-years away from Earth Brown dwarfs are failed stars that cannot sustain core nuclear fusionSubstellar objects bridge the evolutionary gap between giant gas planets and stars

Tags: units, parallax, stars

A parsec is a parallax measurement, not a time: the short answers

Where does this come from, and can I check it?: It is the distance at which Earth's orbit subtends one arcsecond. The figure is taken from Britannica, which is linked in full on this page. Every fact on Mondo Knows names its source rather than repeating an unsourced claim.
Is this really a space fact?: Yes. It sits on the Space shelf, one of 2,600 sourced facts grouped into space, animals, the human body, history, science and more. Category pages collect every fact in the same field.
What else can I read about it?: The links under the fact point to a quiz, game, puzzle or calculator on the same subject, and the shelf below shows related facts. The wording here is original, and quoted phrases are marked as quotations.