Astronomical units to orbital period in days
Type a value in AU to get it in d instantly.
365.3d
That's about the same as Earth. A year out there lasts about 1 Earth years.
Convert the other way: d to AU
What it means
How long is its year?
Kepler’s law here assumes the Sun’s mass and a circular orbit. Real orbits are ellipses, and the semi-major axis is what goes into the formula.
The math
How to convert AU to d
Kepler’s third law: period in years = (distance in AU)^1.5, and back again distance = period^(2/3). Orbital speed falls as 29.78 ÷ √distance km/s.
Example: 1 AU = 365.25 d.
Every unit
Your orbit in every unit
Tables
AU to d conversion table
| AU | d |
|---|---|
| 0.39 AU | 88.9584 d |
| 0.72 AU | 223.146 d |
| 1 AU | 365.25 d |
| 1.52 AU | 684.472 d |
| 2.8 AU | 1,711.3 d |
| 5.2 AU | 4,331.07 d |
| 9.5 AU | 10,694.9 d |
| 19.2 AU | 30,728.6 d |
| 30.1 AU | 60,317 d |
| 39.5 AU | 90,674.6 d |
| 100 AU | 365,250 d |
d to AU conversion table
| d | AU |
|---|---|
| 0.39 d | 0.0104468 AU |
| 0.72 d | 0.0157215 AU |
| 1 d | 0.0195707 AU |
| 1.52 d | 0.0258723 AU |
| 2.8 d | 0.0388787 AU |
| 5.2 d | 0.0587411 AU |
| 9.5 d | 0.0877854 AU |
| 19.2 d | 0.140327 AU |
| 30.1 d | 0.189373 AU |
| 39.5 d | 0.226989 AU |
| 100 d | 0.421638 AU |
Quick answers
Quick answers
- How many d is 1 AU?
- 1 AU is 365.25 d.
- How many d is 10 AU?
- 10 AU is 11,550.2 d.
The units
About these units
Astronomical units (AU)
The Earth–Sun distance, the natural ruler for the solar system.
Orbital period in days (d)
The same period in days, for the fast inner orbits.
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