Astronomical Units
Units for the scale of the solar system and beyond, from the astronomical unit to the parsec. 4 units are listed.
| Unit | Symbol | Quantity | Value in SI |
|---|---|---|---|
| Astronomical unit | au | Length | 149,597,870,700 m (exact) |
| Light-year | ly | Length | 9,460,730,472,580,800 m (exact) |
| Parsec | pc | Length | 648,000/π au ≈ 3.0857 × 10¹⁶ m |
| Julian year | a | Time | 365.25 d = 31,557,600 s (exact) |