Instant · Precise · Universal
28 units available
6 categories total
To convert as to seconds: multiply by 10⁻¹⁸. To convert as to femtoseconds: divide by 1,000.
1 as = 10⁻¹⁸ s = 0.001 fs. Light travels only about 0.3 nm (the width of a water molecule) in one attosecond.
For example, 1 Attosecond (as) = 2.785383e-22 Hour (Sidereal) (h (Sid)).
| Attosecond (as) | Hour (Sidereal) (h (Sid)) |
|---|---|
| 0.1 | 2.785383e-23 |
| 0.5 | 1.392692e-22 |
| 1 | 2.785383e-22 |
| 2 | 5.570766e-22 |
| 5 | 1.392692e-21 |
| 10 | 2.785383e-21 |
| 25 | 6.963458e-21 |
| 50 | 1.392692e-20 |
| 100 | 2.785383e-20 |
| 500 | 1.392692e-19 |
| 1000 | 2.785383e-19 |
The attosecond is a unit of time equal to 10⁻¹⁸ seconds — one quintillionth of a second.
1 as = 10⁻¹⁸ s = 0.001 fs. Light travels only about 0.3 nm (the width of a water molecule) in one attosecond.
To convert as to seconds: multiply by 10⁻¹⁸. To convert as to femtoseconds: divide by 1,000.
No everyday applications yet. Research applications include tracking electron motion and developing future ultrafast electronics.
An attosecond is to one second as one second is to about 31.7 billion years — roughly twice the age of the universe.
Confusing 'as' (attosecond) with the English word 'as'. In scientific texts, context and formatting prevent ambiguity.
The 2023 Nobel Prize in Physics was awarded for attosecond pulse generation — this field is at the frontier of ultrafast science.
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.



© 2026 UntangleTools. All Rights Reserved.