Length · Unit Converter

Convert Earth's Polar Radius to Light Year

Convert earth's polar radii to light years instantly. 1 earth's polar radius = 6.719092e-10 light year — use the live calculator, the exact formula, a conversion table and worked examples. Also check the Light Year to Earth's Polar 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

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.

Astronomical

Light Year

What is a light year?

A light year is the distance light travels in one Julian year in vacuum — exactly 9,460,730,472,580,800 meters (about 9.46×10¹⁵ m). It is the most common unit for expressing inter-stellar distances in non-technical astronomy.

Origin of the light year

Defined as the speed of light (299,792,458 m/s, exact) multiplied by one Julian year (365.25 days × 86400 seconds/day). Both factors are exact, making the light year exact by definition.

Where it is used

Light years are used in popular astronomy, science journalism, and stellar distance descriptions. The nearest star (Proxima Centauri) is 4.24 ly away; the Milky Way is about 100,000 ly across.

When and where it was developed

Concept of distance-as-time used since the 19th century; the modern exact definition follows from the 1983 SI definition of the meter via the speed of light.

Earth's Polar Radius to Light Year conversion formula

The relationship between earth's polar radii and light years:

1 R⊕,p = 6.719092e-10 ly
1 ly = 1.488296e+9 R⊕,p

To convert earth's polar radii to light years, multiply the value in earth's polar radii by 6.719092e-10. To reverse, multiply light years by 1.488296e+9.

How to use this converter

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

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

  1. Write down the value in earth's polar radii (R⊕,p).
  2. Multiply that value by the factor 6.719092e-10.
  3. The product is the equivalent value in light years (ly).
  4. To reverse, multiply the light year value by 1.488296e+9.

Worked examples

Example 1 — Convert 1 R⊕,p to ly:
1 × 6.719092e-10 = 6.719092e-10 ly

Example 2 — Convert 100 R⊕,p to ly:
100 × 6.719092e-10 = 6.719092e-8 ly

Earth's Polar Radius to Light Year conversion table

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

Earth's Polar Radius [R⊕,p]Light Year [ly]
0.016.719092e-12
0.16.719092e-11
16.719092e-10
21.343818e-9
32.015728e-9
42.687637e-9
53.359546e-9
106.719092e-9
201.343818e-8
302.015728e-8
402.687637e-8
503.359546e-8
1006.719092e-8
5003.359546e-7
10006.719092e-7

Frequently asked questions

How many light years is 1 earth's polar radius?
1 earth's polar radius equals 6.719092e-10 light year.
How do I convert earth's polar radii to light years?
Multiply the value in earth's polar radii by 6.719092e-10 to get light years.
How do I convert light years back to earth's polar radii?
Multiply the value in light years by 1.488296e+9, or use the Light Year to Earth's Polar Radius converter.
How many light years is 100 earth's polar radii?
100 earth's polar radii equals 6.719092e-8 light years, because 100 × 6.719092e-10 = 6.719092e-8.

Convert Earth's Polar Radius to other length units

Show all Earth's Polar Radius conversions

Sources & references

Conversion factor (1 R⊕,p = 6.719092e-10 ly) verified against the following authoritative sources:

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