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High-Tech Channel Hitachi High-Tech GLOBAL

Distance unit that is longer than “light years”!

Symbol: pc / Base data: length.
Distance at which one astronomical unit subtends an angle of one arcsecond. 3.262 light years

Shown with the use of “stellar parallax”

When looking at the radius of the revolution orbit of the earth against distant stars or, in other words, when looking at the earth and the sun, their angles look different (stellar parallax). When this difference is n-arcseconds (1/3600 of a degree), the distance between the sun and the star is 1/n parsec. It is 1 parsec for 1 arcsecond. It is equivalent to 3.262 light years.