Convert Hours to Attoseconds
Convert Hours (h) to Attoseconds (as) instantly and accurately.
Conversion Formula
as = h × 3.600000000e+21
About Hours
An hour (h) = exactly 3,600 s. The 24-hour day traces to ancient Egypt (10 daylight hours + 2 twilight + 12 night star-rise periods). Time zones are integer or half-hour UTC offsets (exceptions: India +5:30, Nepal +5:45). The kilowatt-hour = 3,600,000 J; Tc-99m half-life = 6.0067 h. Drug dosing and pharmacokinetics are expressed in hours. 1 h = 3,600 s = 60 min = 1/24 day.
About Attoseconds
An attosecond (as) = 10⁻¹⁸ s - the timescale of electron dynamics in atoms. The Bohr-model orbital period in hydrogen is ~152 as. Electron tunnelling through atomic potential barriers takes a few hundred as. The 2023 Nobel Prize in Physics (Agostini, Krausz, L'Huillier) honoured methods for generating sub-100 as pulses via high-harmonic generation in Ti:sapphire lasers. 1 as = 10⁻¹⁸ s = 1,000 zs.
Quick Reference Table
| Hours (h) | Attoseconds (as) |
|---|---|
| 1 h | 3.6 × 1021 as |
| 2 h | 7.2 × 1021 as |
| 5 h | 1.8 × 1022 as |
| 10 h | 3.6 × 1022 as |
| 25 h | 9 × 1022 as |
| 50 h | 1.8 × 1023 as |
| 100 h | 3.6 × 1023 as |