500pc是多少ly？
500pc = 1,630.7819ly
是1,630.7819ly，所以说成1,631ly也没问题——四舍五入的误差在0.5%以内。
反过来，500ly是多少pc？
500ly = 153.3007pc
计算公式: ly = pc × 3.261564
该数值前后的 pc → ly
50 pc163.0782ly
100 pc326.1564ly
150 pc489.2346ly
200 pc652.3128ly
250 pc815.3909ly
300 pc978.4691ly
350 pc1,141.5473ly
400 pc1,304.6255ly
450 pc1,467.7037ly
500 pc1,630.7819ly
550 pc1,793.8601ly
600 pc1,956.9383ly
650 pc2,120.0165ly
700 pc2,283.0946ly
750 pc2,446.1728ly
800 pc2,609.251ly
850 pc2,772.3292ly
900 pc2,935.4074ly
950 pc3,098.4856ly
1,000 pc3,261.5638ly