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Kepler's Third Law Calculator

Science & Engineering

T²=a³, planet table

Quick Answer

Kepler's Third Law Calculator: T²=a³, planet table. Kepler's Third Law Calculator uses standard science & engineering formulas to compute accurate results instantly.

Orbital period at 1.524 AU

1.881 years

T² = a³

Period (years)1.8814
Period (days)687.2
Semi-major axis1.5240 AU
Distance (million km)228.0

Calculation steps

  1. 1Cube the semi-major axis: a³ = 1.5240³ = 3.5396
  2. 2Take the square root: T = √(a³) = √3.5396 = 1.8814 years
T² = a³ with T in years and a in AU only holds for orbits around the Sun (T²/a³ = 1 is really a statement about solar mass). For satellites around Earth or other bodies, use the full form T² = 4π²a³/(GM). The Moon preset above is illustrative only.

Solar system planets

Planeta (AU)T (years)T²/a³
Mercury0.3870.2411.0021
Venus0.7230.6151.0008
Earth111.0000
Mars1.5241.8810.9996
Jupiter5.20311.860.9986
Saturn9.53729.450.9999
Uranus19.1984.020.9989
Neptune30.07164.80.9989

Kepler's third law: T²/a³ ≈ 1 when T is in years and a in AU (orbiting the Sun). 1 AU = 149.6 million km.

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How to Use

  1. Enter known quantities: fill values and confirm units in the Kepler's Third Law Calculator.
  2. Instant solution: unknowns solve live with the formula shown transparently.
  3. Use constant/material tables: standard physical constants and material data are listed on this page.
  4. Compare conditions: change inputs to compare scenarios.

Key Points

  • Kepler's Third Law Calculator is a free online science & engineering tool — open and use, no sign-up.
  • All calculations run locally in your browser; your data never leaves the device.
  • Key capability: T²=a³, planet table.
  • Results come with formulas and reference tables so you can verify every number.

Formula & How It Works

Kepler's Third Law Calculator formula

Kepler's Third Law Calculator uses standard science & engineering formulas to compute accurate results instantly.

FAQ

How do I use the Kepler's Third Law Calculator?
Open the page and fill in the input fields — results update automatically. T²=a³, planet table.
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Yes. Standard formulas and conversion factors are used and verified.
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Source & Updates

Based on CODATA recommended constants and standard physics formulas. Last updated: 2025-07

Last updated:

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Results provided by this tool are for reference only and do not constitute professional advice.