Convert Light Year to Earth's Polar Radius
Convert light years to earth's polar radii instantly. 1 light year = 1.488296e+9 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 Light Year converter for the reverse conversion.
Units explained
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.
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.
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.
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
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.
Light Year to Earth's Polar Radius conversion formula
The relationship between light years and earth's polar radii:
To convert light years to earth's polar radii, multiply the value in light years by 1.488296e+9. To reverse, multiply earth's polar radii by 6.719092e-10.
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 Light Year converter for the reverse direction.
Step-by-step: convert light years to earth's polar radii
- Write down the value in light years (ly).
- Multiply that value by the factor 1.488296e+9.
- The product is the equivalent value in earth's polar radii (R⊕,p).
- To reverse, multiply the earth's polar radius value by 6.719092e-10.
Worked examples
Example 1 — Convert 1 ly to R⊕,p:
1 × 1.488296e+9 = 1.488296e+9 R⊕,p
Example 2 — Convert 100 ly to R⊕,p:
100 × 1.488296e+9 = 1.488296e+11 R⊕,p
Light Year to Earth's Polar Radius conversion table
Standard reference values for converting light years to earth's polar radii:
| Light Year [ly] | Earth's Polar Radius [R⊕,p] |
|---|---|
| 0.01 | 1.488296e+7 |
| 0.1 | 1.488296e+8 |
| 1 | 1.488296e+9 |
| 2 | 2.976593e+9 |
| 3 | 4.464889e+9 |
| 4 | 5.953185e+9 |
| 5 | 7.441481e+9 |
| 10 | 1.488296e+10 |
| 20 | 2.976593e+10 |
| 30 | 4.464889e+10 |
| 40 | 5.953185e+10 |
| 50 | 7.441481e+10 |
| 100 | 1.488296e+11 |
| 500 | 7.441481e+11 |
| 1000 | 1.488296e+12 |
Frequently asked questions
How many earth's polar radii is 1 light year?
How do I convert light years to earth's polar radii?
How do I convert earth's polar radii back to light years?
How many earth's polar radii is 100 light years?
Popular length unit conversions
Convert Light Year to other length units
Show all Light Year conversions
Metric / SI (4 units)
Imperial / US Customary (4 units)
Astronomical (8 units)
Sources & references
Conversion factor (1 ly = 1.488296e+9 R⊕,p) 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.