Convert Square Arcsecond to Steradian
Enter the number of square arcseconds that you want to convert to steradians.
How to Convert Square Arcseconds to Steradians
The square arcsecond and steradian are both units of solid angle. 1 steradian equals 42545225575 square arcseconds. This means to convert square arcseconds to steradians, you divide by 42545225575.
Formula
Step-by-Step Example
Convert 5 arcsec² to steradians:
We need to convert square arcseconds to steradians
Since 1 sr = 42545225575 arcsec², divide by 42545225575
5 ÷ 42545225575 = 1.17522e-10
5 arcsec² = 1.17522e-10 sr
Square Arcsecond to Steradian Conversion Table
Quick reference table for common square arcsecond to steradian conversions. Click any value for detailed calculation.
| Square Arcseconds (arcsec²) | Steradians (sr) |
|---|---|
| 0.1 arcsec² | 2.35044e-12 sr |
| 0.5 arcsec² | 1.17522e-11 sr |
| 1 arcsec² | 2.35044e-11 sr |
| 2 arcsec² | 4.70088e-11 sr |
| 5 arcsec² | 1.17522e-10 sr |
| 10 arcsec² | 2.35044e-10 sr |
| 25 arcsec² | 5.8761e-10 sr |
| 50 arcsec² | 1.17522e-9 sr |
| 100 arcsec² | 2.35044e-9 sr |
About These Units
Square Arcsecond (arcsec²)
A square arcsecond equals (1/3600)² of a square degree or about 2.35×10⁻¹¹ steradians. One square arcminute = 3,600 square arcseconds. Measures individual star disks, exoplanet host star separation, and high-resolution imaging pixels.
Steradian (sr)
The steradian (sr) is the SI unit of solid angle—the 3D analog of the radian. One steradian is the solid angle subtended by a spherical cap with area r² on a sphere of radius r. A complete sphere subtends 4π ≈ 12.566 steradians. Used in radiometry, photometry, and antenna theory.
Frequently Asked Questions
How do I convert square arcseconds to steradians?
To convert square arcseconds to steradians, divide the value by 42545225575. For example, 10 arcsec² = 2.35044e-10 sr.
How many steradians are in 1 square arcsecond?
1 square arcsecond equals 2.35044e-11 steradians.
What is the formula for square arcseconds to steradians?
The formula is: sr = arcsec² ÷ 42545225575.