1 Gly = 1,000,000,000 light years or 9.461*1026 cm.
1 Gyr = 1,000,000,000 years.
1 Mpc = 1,000,000 parsecs = 3.08568*1024 cm, or 3,261,566 light years.

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See the advanced and light travel time versions of the calculator.

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© 1999-2016 Edward L. Wright. If you use this calculator while preparing a paper, please cite Wright (2006, PASP, 118, 1711). Last modified on