Hour to Hour (Sidereal) Converter
Unit Converter
Instant · Precise · Universal
28 units available
6 categories total
How to Convert Hour to Hour (Sidereal)
To convert hours to minutes: multiply by 60. To convert hours to seconds: multiply by 3,600.
1 h = 60 min = 3,600 s = 3.6 × 10⁶ ms. There are 24 hours in a day and 8,760 in a non-leap year.
For example, 1 Hour (h) = 1.00273792 Hour (Sidereal) (h (Sid)).
Hour to Hour (Sidereal) — Common Values
| Hour (h) | Hour (Sidereal) (h (Sid)) |
|---|---|
| 0.1 | 0.100273792 |
| 0.5 | 0.5013689601 |
| 1 | 1.00273792 |
| 2 | 2.00547584 |
| 5 | 5.013689601 |
| 10 | 10.0273792 |
| 25 | 25.068448 |
| 50 | 50.13689601 |
| 100 | 100.273792 |
| 500 | 501.3689601 |
| 1000 | 1002.73792 |
About Hour (h)
Definition
The hour is a unit of time equal to 60 minutes, or 3,600 seconds.
Mathematical Relationship
1 h = 60 min = 3,600 s = 3.6 × 10⁶ ms. There are 24 hours in a day and 8,760 in a non-leap year.
Conversion Formula
To convert hours to minutes: multiply by 60. To convert hours to seconds: multiply by 3,600.
Practical Applications
Work schedules, flight durations, speed limits (km/h, mph), cooking times, and pay rates (hourly wages).
Interesting Facts
Before mechanical clocks, 'hours' varied by season — a summer daytime hour was longer than a winter one. These were called 'temporal hours.'
Common Mistakes
Converting decimal hours to minutes/seconds incorrectly: 2.5 h = 2 h 30 min, not 2 h 50 min. Think base-60.
Educational Tips
The kilowatt-hour (kWh) on your electric bill is energy = power × time. 1 kWh = using 1,000 watts for 1 hour.
About Hour (Sidereal) (h (Sid))
Definition
The sidereal hour is 1/24 of a sidereal day — approximately 3,590.17 seconds (59 minutes and 50.17 seconds in solar time).
Mathematical Relationship
1 sidereal hour = 3,590.17 solar seconds ≈ 59 min 50.17 s in solar time. 24 sidereal hours = 1 sidereal day.
Conversion Formula
To convert sidereal hours to solar seconds: multiply by 3,590.17. To solar hours: multiply by 0.99727.
Practical Applications
Right ascension in celestial coordinates is measured in hours (0–24 h of sidereal time), directly using sidereal hours.
Interesting Facts
Right ascension is measured in hours: 1 h of RA = 15° of sky. The entire sky is 24 sidereal hours in rotation.
Common Mistakes
Treating sidereal hours as exactly 60 solar minutes. The ~10-second difference matters for precision tracking.
Educational Tips
If you use a star-tracking telescope, it rotates once per sidereal day (23h 56m). Each sidereal hour, it covers 15° of sky.