Convert Sidereal Years (a-sr) to Tropical Years (at) | a-sr in at

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Let's convert Sidereal Years (a-sr) to Tropical Years (at)

This quick and easy calculator will convert Sidereal Years (a-sr) to Tropical Years (at) and show formula, brief history on the units and quick maths for the conversion.

Enter Sidereal Years to convert to Tropical Years


Quick Reference for Converting Sidereal Years to Tropical Years

Formula
at = a-sr x 1
Quick Rough Maths
Tropical Years and Sidereal Years are approximately equal
Sidereal Years (a-sr) in 1 Tropical Year
There are 1 Sidereal Years in 1 Tropical Year
Tropical Years (at) in 1 Sidereal Year
There are 1 Tropical Years in 1 Sidereal Year

Unit Information

Sidereal Year
/sʌɪˈdɪərɪəl jɪə,jəː/
Symbol: a-sr
Unit System: SI

What is the Sidereal Year?

The sidereal year is a unit of time that is a multiple of an SI unit. We have used the symbol a-sr.

From the Latin ‘sidus’ for ‘star’, sidereal is a term used to describe the orbital time of the earth or an object to complete one full cycle with respect to a fixed, distant star or constellation pattern.

The sidereal year is defined as 365.242 190 402 days of 86,400 SI seconds. This is 20 minutes and 24.5 seconds longer than a tropical year.

Tropical Year
/ˈtrɒpɪk(ə)l jɪə,jəː/
Symbol: at
Unit System: SI

What is the Tropical Year?

The tropical year is a unit of time that is a multiple of an SI unit. We have used the symbol at.

The average tropical year up to the year 2000 was 365.2422 days of 86400 seconds.

The phrase “tropical” comes from the Greek for “turn”; tropikos. Following this, and where the “turn” referred to is the same as that defining the tropics of Capricorn and Cancer (the extreme latitudes North and South where the sun can still appear directly overhead or perpendicular to the Earth’s surface); a tropical year is known as the time it takes the sun to complete a full cycle of seasons and return to the same relative position to the observer on Earth.

In 1627, Johannes Kepler used the findings of Tycho Brahe and Waltherus (the Rudolphine Tables) to establish the mean tropical year as 365 solar days, 5 hours, 48 minutes and 45 seconds.


Conversion Tables for Sidereal Years (a-sr) to Tropical Years (at)