Convert Light Years to Megaparsecs
Convert Light Years (ly) to Megaparsecs (Mpc) instantly and accurately.
Conversion Formula
Mpc = ly × 3.066013938e-7
About Light Years
A light year (ly) is the distance light travels in one year through a vacuum, approximately 9.46 trillion kilometers. This is the primary unit for measuring stellar distances. Our nearest star neighbor, Proxima Centauri, is 4.24 light years away, meaning its light takes over 4 years to reach us. The center of our Milky Way galaxy is about 26,000 light years distant, and the nearest large galaxy (Andromeda) is 2.5 million light years away. When we observe distant objects, we're literally seeing them as they were years ago.
About Megaparsecs
A megaparsec (Mpc) is one million parsecs or 3.26 million light years, the standard unit for measuring intergalactic distances. The Andromeda Galaxy is about 0.77 megaparsecs away, while most galaxies in the observable universe are measured in megaparsecs. The Local Group of galaxies spans about 3 megaparsecs. Astronomers use megaparsecs in combination with redshift measurements to calculate distances to distant galaxies and study the expansion of the universe. The Hubble constant, describing cosmic expansion, is expressed in kilometers per second per megaparsec.
Quick Reference Table
| Light Years (ly) | Megaparsecs (Mpc) |
|---|---|
| 1 ly | 3.066 × 10-7 Mpc |
| 2 ly | 6.132 × 10-7 Mpc |
| 5 ly | 1.533 × 10-6 Mpc |
| 10 ly | 3.066 × 10-6 Mpc |
| 25 ly | 7.665 × 10-6 Mpc |
| 50 ly | 1.533 × 10-5 Mpc |
| 100 ly | 3.066 × 10-5 Mpc |