Length · Unit Converter

Convert Sun's Radius to Earth's Polar Radius

Convert sun's radii to earth's polar radii instantly. 1 sun's radius = 109.4426839367 earth's polar radius — use the live calculator, the exact formula, a conversion table and worked examples. Also check the Earth's Polar Radius to Sun's Radius converter for the reverse conversion.

Written by Sunith Babu L, Ph.D., Lead Engineer Reviewed by Girish V Kulkarni Ph.D.
Length category 2 min read Published Last reviewed Updated

Units explained

Astronomical

Sun's Radius

What is a sun's radius?

The Sun's radius is approximately 695,700 km (6.957×10⁸ m), defined as the IAU 2015 nominal solar radius for use in stellar physics and exoplanet research.

Origin of the sun's radius

The IAU (International Astronomical Union) Resolution B3 in 2015 defined a nominal solar radius of exactly 6.957×10⁸ m to serve as a stable reference, independent of actual measurement-uncertainty variations in the real Sun.

Where it is used

Solar radii are used in stellar physics, exoplanet characterisation, and any context where a star's size is expressed relative to the Sun. Most stellar radius measurements are quoted in solar-radius units rather than meters.

When and where it was developed

Defined exactly at 6.957×10⁸ m by IAU Resolution B3 in 2015.

Astronomical

Earth's Polar Radius

What is a earth's polar radius?

Earth's polar radius is the distance from the planet's center to either pole, approximately 6,356,752 meters under the WGS84 geodetic reference system. The polar radius is about 21 km shorter than the equatorial radius due to Earth's oblate spheroid shape.

Origin of the earth's polar radius

Derived from WGS84's flattening parameter (f ≈ 1/298.257); the difference from the equatorial radius is the geometric signature of Earth's rotational oblateness.

Where it is used

Earth's polar radius is used in geodesy, satellite-orbit calculations, and global cartography. Together with the equatorial radius it defines Earth's reference ellipsoid in WGS84.

When and where it was developed

Derived from the WGS84 reference ellipsoid adopted in 1984; the value is computed from the equatorial radius minus the oblateness.

Sun's Radius to Earth's Polar Radius conversion formula

The relationship between sun's radii and earth's polar radii:

1 R☉ = 109.4426839367 R⊕,p
1 R⊕,p = 0.0091372028 R☉

To convert sun's radii to earth's polar radii, multiply the value in sun's radii by 109.4426839367. To reverse, multiply earth's polar radii by 0.0091372028.

How to use this converter

Type a value into the calculator. The result in earth's polar radii updates as you type. Tap a quick value, copy the result with one click, or use the swap arrow to jump straight to the Earth's Polar Radius to Sun's Radius converter for the reverse direction.

Step-by-step: convert sun's radii to earth's polar radii

  1. Write down the value in sun's radii (R☉).
  2. Multiply that value by the factor 109.4426839367.
  3. The product is the equivalent value in earth's polar radii (R⊕,p).
  4. To reverse, multiply the earth's polar radius value by 0.0091372028.

Worked examples

Example 1 — Convert 1 R☉ to R⊕,p:
1 × 109.4426839367 = 109.4426839367 R⊕,p

Example 2 — Convert 100 R☉ to R⊕,p:
100 × 109.4426839367 = 10944.2683936702 R⊕,p

Sun's Radius to Earth's Polar Radius conversion table

Standard reference values for converting sun's radii to earth's polar radii:

Sun's Radius [R☉]Earth's Polar Radius [R⊕,p]
0.011.0944268394
0.110.9442683937
1109.4426839367
2218.8853678734
3328.3280518101
4437.7707357468
5547.2134196835
101094.426839367
202188.853678734
303283.2805181011
404377.7073574681
505472.1341968351
10010944.2683936702
50054721.3419683511
1000109442.6839367023

Frequently asked questions

How many earth's polar radii is 1 sun's radius?
1 sun's radius equals 109.4426839367 earth's polar radius.
How do I convert sun's radii to earth's polar radii?
Multiply the value in sun's radii by 109.4426839367 to get earth's polar radii.
How do I convert earth's polar radii back to sun's radii?
Multiply the value in earth's polar radii by 0.0091372028, or use the Earth's Polar Radius to Sun's Radius converter.
How many earth's polar radii is 100 sun's radii?
100 sun's radii equals 10944.2683936702 earth's polar radii, because 100 × 109.4426839367 = 10944.2683936702.

Convert Sun's Radius to other length units

Show all Sun's Radius conversions

Sources & references

Conversion factor (1 R☉ = 109.4426839367 R⊕,p) verified against the following authoritative sources:

Results are provided for general reference. Verify critical measurements against an authoritative standard.