Instant · Precise · Universal
28 units available
6 categories total
To convert sidereal hours to solar seconds: multiply by 3,590.17. To solar hours: multiply by 0.99727.
1 sidereal hour = 3,590.17 solar seconds ≈ 59 min 50.17 s in solar time. 24 sidereal hours = 1 sidereal day.
For example, 1 Hour (Sidereal) (h (Sid)) = 0.002968064153 Fortnight (fn).
| Hour (Sidereal) (h (Sid)) | Fortnight (fn) |
|---|---|
| 0.1 | 0.0002968064153 |
| 0.5 | 0.001484032077 |
| 1 | 0.002968064153 |
| 2 | 0.005936128307 |
| 5 | 0.01484032077 |
| 10 | 0.02968064153 |
| 25 | 0.07420160384 |
| 50 | 0.1484032077 |
| 100 | 0.2968064153 |
| 500 | 1.484032077 |
| 1000 | 2.968064153 |
The sidereal hour is 1/24 of a sidereal day — approximately 3,590.17 seconds (59 minutes and 50.17 seconds in solar time).
1 sidereal hour = 3,590.17 solar seconds ≈ 59 min 50.17 s in solar time. 24 sidereal hours = 1 sidereal day.
To convert sidereal hours to solar seconds: multiply by 3,590.17. To solar hours: multiply by 0.99727.
Right ascension in celestial coordinates is measured in hours (0–24 h of sidereal time), directly using sidereal hours.
Right ascension is measured in hours: 1 h of RA = 15° of sky. The entire sky is 24 sidereal hours in rotation.
Treating sidereal hours as exactly 60 solar minutes. The ~10-second difference matters for precision tracking.
If you use a star-tracking telescope, it rotates once per sidereal day (23h 56m). Each sidereal hour, it covers 15° of sky.
A fortnight is a unit of time equal to 14 days, or two weeks (1,209,600 seconds).
1 fortnight = 14 d = 2 wk = 336 h = 1,209,600 s.
To convert fortnights to days: multiply by 14. To convert fortnights to weeks: multiply by 2.
Fortnightly pay cycles (common in Australia and UK), rental payment periods, and magazine publication schedules.
In Australia, being paid 'fortnightly' is the most common pay cycle. The FFF system defines speed in furlongs per fortnight.
Americans may be unfamiliar with the term. In US English, 'two weeks' is the standard equivalent.
Fortnight = fourteen nights. In countries where it's common, it's as natural as saying 'week' — just meaning two of them.



© 2026 UntangleTools. All Rights Reserved.