Convert Earth's Polar Radius to Sun's Radius
Convert earth's polar radii to sun's radii instantly. 1 earth's polar radius = 0.0091372028 sun's radius — use the live calculator, the exact formula, a conversion table and worked examples. Also check the Sun's Radius to Earth's Polar Radius converter for the reverse conversion.
Units explained
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.
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.
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.
Derived from the WGS84 reference ellipsoid adopted in 1984; the value is computed from the equatorial radius minus the oblateness.
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.
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.
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.
Defined exactly at 6.957×10⁸ m by IAU Resolution B3 in 2015.
Earth's Polar Radius to Sun's Radius conversion formula
The relationship between earth's polar radii and sun's radii:
To convert earth's polar radii to sun's radii, multiply the value in earth's polar radii by 0.0091372028. To reverse, multiply sun's radii by 109.4426839367.
How to use this converter
Type a value into the calculator. The result in sun's 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 Sun's Radius to Earth's Polar Radius converter for the reverse direction.
Step-by-step: convert earth's polar radii to sun's radii
- Write down the value in earth's polar radii (R⊕,p).
- Multiply that value by the factor 0.0091372028.
- The product is the equivalent value in sun's radii (R☉).
- To reverse, multiply the sun's radius value by 109.4426839367.
Worked examples
Example 1 — Convert 1 R⊕,p to R☉:
1 × 0.0091372028 = 0.0091372028 R☉
Example 2 — Convert 100 R⊕,p to R☉:
100 × 0.0091372028 = 0.9137202817 R☉
Earth's Polar Radius to Sun's Radius conversion table
Standard reference values for converting earth's polar radii to sun's radii:
| Earth's Polar Radius [R⊕,p] | Sun's Radius [R☉] |
|---|---|
| 0.01 | 9.137203e-5 |
| 0.1 | 0.0009137203 |
| 1 | 0.0091372028 |
| 2 | 0.0182744056 |
| 3 | 0.0274116085 |
| 4 | 0.0365488113 |
| 5 | 0.0456860141 |
| 10 | 0.0913720282 |
| 20 | 0.1827440563 |
| 30 | 0.2741160845 |
| 40 | 0.3654881127 |
| 50 | 0.4568601409 |
| 100 | 0.9137202817 |
| 500 | 4.5686014087 |
| 1000 | 9.1372028173 |
Frequently asked questions
How many sun's radii is 1 earth's polar radius?
How do I convert earth's polar radii to sun's radii?
How do I convert sun's radii back to earth's polar radii?
How many sun's radii is 100 earth's polar radii?
Popular length unit conversions
Convert Earth's Polar Radius to other length units
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Metric / SI (4 units)
Imperial / US Customary (4 units)
Astronomical (8 units)
Sources & references
Conversion factor (1 R⊕,p = 0.0091372028 R☉) verified against the following authoritative sources:
- BIPM — The International System of Units (SI Brochure 9th ed.)
Official BIPM publication defining the seven SI base units (including the meter) and the rules for their use. The global authority on units of measurement.
- NIST — Guide to the SI
US National Institute of Standards and Technology reference covering the SI base and derived units with definitions and usage rules for US technical practice.
- NIST Special Publication 811 — Guide for the Use of the International System of Units
Detailed NIST guide covering exact conversion factors between SI and US customary units along with formatting and rounding conventions.
- NIST — Refinement of values for the yard and pound (Federal Register 1959)
The treaty (signed by US
- International Astronomical Union — System of Astronomical Constants
The IAU defines astronomical units including the AU (149597870700 m exactly) light-year and parsec used in astronomy and astrophysics.