Hours, minutes, seconds to radians
Type a value in RA to get it in rad instantly.
4.874rad
That's about the same as Vega.
What it means
Where is that on the sky?
Star positions are J2000. Right ascension minutes and seconds are time units, 15 times larger than arcminutes and arcseconds.
The math
How to convert RA to rad
degrees = (h + m/60 + s/3600) × 15; hours = degrees ÷ 15.
Example: 18h 36m 56.2s RA = 4.87355 rad.
Every unit
That position in every unit
Tables
RA to rad conversion table
| RA | rad |
|---|---|
| 0h 00m 00.0s RA | 0 rad |
| 1h 00m 00.0s RA | 0.261799 rad |
| 2h 00m 00.0s RA | 0.523599 rad |
| 3h 00m 00.0s RA | 0.785398 rad |
| 4h 00m 00.0s RA | 1.0472 rad |
| 5h 00m 00.0s RA | 1.309 rad |
| 6h 00m 00.0s RA | 1.5708 rad |
| 8h 00m 00.0s RA | 2.0944 rad |
| 10h 00m 00.0s RA | 2.61799 rad |
| 12h 00m 00.0s RA | 3.14159 rad |
| 14h 00m 00.0s RA | 3.66519 rad |
| 16h 00m 00.0s RA | 4.18879 rad |
| 18h 00m 00.0s RA | 4.71239 rad |
| 20h 00m 00.0s RA | 5.23599 rad |
| 22h 00m 00.0s RA | 5.75959 rad |
| 23h 00m 00.0s RA | 6.02139 rad |
rad to RA conversion table
| rad | RA |
|---|---|
| 0 rad | 0h 00m 00.0s RA |
| 0.262 rad | 1h 00m 02.8s RA |
| 0.524 rad | 2h 00m 05.5s RA |
| 0.785 rad | 2h 59m 54.5s RA |
| 1.05 rad | 4h 00m 38.5s RA |
| 1.31 rad | 5h 00m 13.8s RA |
| 1.57 rad | 5h 59m 49.0s RA |
| 2.09 rad | 7h 58m 59.6s RA |
| 2.62 rad | 10h 00m 27.6s RA |
| 3.14 rad | 11h 59m 38.1s RA |
| 3.67 rad | 14h 01m 06.1s RA |
| 4.19 rad | 16h 00m 16.6s RA |
| 4.71 rad | 17h 59m 27.1s RA |
| 5.24 rad | 20h 00m 55.2s RA |
| 5.76 rad | 22h 00m 05.7s RA |
| 6.02 rad | 22h 59m 40.9s RA |
Quick answers
Quick answers
- How many rad is 1h 00m 00.0s RA?
- 1h 00m 00.0s RA is 0.261799 rad.
- How many rad is 10h 00m 00.0s RA?
- 10h 00m 00.0s RA is 2.61799 rad.
- How many rad is 18h 36m 56.2s RA?
- 18h 36m 56.2s RA is 4.87355 rad.
The units
About these units
Hours, minutes, seconds (RA)
Right ascension written 5h 35m 17.2s.
Radians (rad)
Right ascension in radians.
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