Parsecs to Lightyears (pc to ly)

Lightyears to Parsecs (Swap Units)


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Parsecs to Lightyears formula

ly =
pc * 3.2616
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More information: Parsecs


Astronomers used trigonometry to calculate the distance to stars long before the term parsec was coined, but the new unit made it easier to conceptualise unfathomable distances.

A parsec is the distance from the sun to an astronomical object which has a parallax angle of one arcsecond (1/3600 of a degree). The parallax angle is found by measuring the parallax motion (or apparent movement of a star relative to stable, more distant stars) when the star is observed from opposite sides of the Sun (an interval of six months on Earth). The parallax angle is obtained by halving the angular difference in measurements.

Once the parallax angle is established you can calculate the distance to a star using trigonometry, because we know Earth’s distance from the Sun. The distance from the Sun of a body with a parallax angle of 1 arcsecond was thus defined as a unit and, thanks to Turner, named the parsec.

With the parsec defined, deriving and describing huge distances became easy, since a distance i


Parsecs to Lightyears formula

ly =
pc * 3.2616


A lightyear is the distance that light travels in one year. Since there are various definitions for the length of a year, there are correspondingly slightly different values for a lightyear. One lightyear corresponds to about 9.461e15 m, 5.879e12 mi, or 63239.7 AU, or 0.3066 pc.


Parsecs to Lightyears table

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< Smaller Values Larger Values >
Parsecs Lightyears
0pc 0.00ly
1pc 3.26ly
2pc 6.52ly
3pc 9.78ly
4pc 13.05ly
5pc 16.31ly
6pc 19.57ly
7pc 22.83ly
8pc 26.09ly
9pc 29.35ly
10pc 32.62ly
11pc 35.88ly
12pc 39.14ly
13pc 42.40ly
14pc 45.66ly
15pc 48.92ly
16pc 52.19ly
17pc 55.45ly
18pc 58.71ly
19pc 61.97ly
Parsecs Lightyears
20pc 65.23ly
21pc 68.49ly
22pc 71.75ly
23pc 75.02ly
24pc 78.28ly
25pc 81.54ly
26pc 84.80ly
27pc 88.06ly
28pc 91.32ly
29pc 94.59ly
30pc 97.85ly
31pc 101.11ly
32pc 104.37ly
33pc 107.63ly
34pc 110.89ly
35pc 114.15ly
36pc 117.42ly
37pc 120.68ly
38pc 123.94ly
39pc 127.20ly
Parsecs Lightyears
40pc 130.46ly
41pc 133.72ly
42pc 136.99ly
43pc 140.25ly
44pc 143.51ly
45pc 146.77ly
46pc 150.03ly
47pc 153.29ly
48pc 156.56ly
49pc 159.82ly
50pc 163.08ly
51pc 166.34ly
52pc 169.60ly
53pc 172.86ly
54pc 176.12ly
55pc 179.39ly
56pc 182.65ly
57pc 185.91ly
58pc 189.17ly
59pc 192.43ly