Convert Sidereal Days to Planck Time

Convert Sidereal Days (sid.d) to Planck Time (t_P) instantly and accurately.

Sidereal Days (sid.d)
Planck Time (t_P)

Conversion Formula

t_P = sid.d × 1.598221905e+48

About Sidereal Days

A sidereal day = Earth's rotation period relative to the stars = 23 h 56 min 4.0905 s = 86,164.0905 s - ~3 min 56 s shorter than the 24 h solar day because Earth advances ~1° in its orbit each day. Equatorial telescope mounts rotate at one turn per sidereal day to track stars. VLBI, GPS orbit determination, and polar-motion monitoring use sidereal rotation as their reference. 1 sid. day = 86,164.0905 s.

About Planck Time

The Planck time (t_P) = √(ℏG/c⁵) ≈ 5.391 × 10⁻⁴⁴ s — the time for light to travel one Planck length (~1.616 × 10⁻³⁵ m). Below this scale, general relativity and quantum mechanics both break down; a theory of quantum gravity is needed. No physical process or instrument approaches this timescale — it is a theoretical lower bound. Introduced by Max Planck in 1899. 1 t_P ≈ 5.391 × 10⁻⁴⁴ s.

Quick Reference Table

Sidereal Days (sid.d)Planck Time (t_P)
1 sid.d1.598 × 1048 t_P
2 sid.d3.196 × 1048 t_P
5 sid.d7.991 × 1048 t_P
10 sid.d1.598 × 1049 t_P
25 sid.d3.996 × 1049 t_P
50 sid.d7.991 × 1049 t_P
100 sid.d1.598 × 1050 t_P

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