What is 81d in Sidereal Seconds?

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What is 81 Days (81d) in Sidereal Seconds (s-sr)?

What is 81d in s-sr? Convert 81 Days (81d) to Sidereal Seconds (s-sr) and show formula, brief history on the units and quick maths for the conversion.

Enter Days to convert to Sidereal Seconds


Quick Reference for Converting Days to Sidereal Seconds

Formula
s-sr = d x 86636.56
Quick Rough Maths
To get the Sidereal Seconds, multiply the number of Days by 86.6 thousand
Days (d) in 1 Sidereal Second
There are 0 Days in 1 Sidereal Second
Sidereal Seconds (s-sr) in 1 Day
There are 86636.56 Sidereal Seconds in 1 Day

Unit Information

Day
/deɪ/
Symbol: d
Unit System: SI

What is the Day?

The day is a unit of time and is an SI-derived unit with the symbol d.

On Earth, it is defined as 86,400 seconds and is approximately the time it takes for the earth to complete a full rotation around its axis. In the earlier days, this was measured by waiting for a cast shadow to match a template drawn from the previous day's shadow.

There are 365 days in a year and, on average, 30.42 days in a month.

The unit day has many different variants; depending on what is used to measure the Earth's rotation. In a sidereal day (a rotation with respect to a distant star or constellation, not the sun), there is actually 4 minutes less than 24 hours in a cycle.

Sidereal Second
/sʌɪˈdɪərɪəlˈsɛk(ə)nd/
Symbol: s-sr
Unit System: SI

What is the Sidereal Second?

The sidereal second is a unit of time used by astronomers and is derived from the SI unit system. We have used the symbol s-sr.

1 sidereal second is 1/60 of a sidereal minute. This is derived ultimately from the sidereal day which is the time taken (in solar seconds) for the Earth to complete one rotation with respect to a distant star or constellation.

Like with normal seconds, minutes, hours and days, there are still 60 x 60 x 24 seconds in a day, but the day itself is approximately 23 h 56 min and 4.1 s in (normal) seconds.


Conversion Tables for Days (d) to Sidereal Seconds (s-sr)