Converting from Day (d) to Sidereal Year (SY) in Time

What is Day (d)

A day (d) is the time it takes for a planet to complete one rotation on its axis. On Earth, a day is equivalent to 24 hours.

What is Sidereal Year (SY)

A sidereal year (SY) is the time it takes for a planet to complete one full orbit around the sun relative to the stars. It is slightly longer than the tropical year due to the precession of the equinoxes.

Conversion Formulas

To convert from days (d) to sidereal years (SY):

SY=365.2564d​

To convert from sidereal years (SY) to days (d):

d=SY×365.2564

Examples

1. Converting 6 days to sidereal years:

SY=365.25646​=0.01642682SY

2. Converting 15 days to sidereal years:

SY=365.256415​=0.04106705SY

3. Converting 8 days to sidereal years:

SY=365.25648​=0.02190242SY

Use this page to perform converting from Day (d) to Sidereal Year (SY)