How to use the hubble's law calculator
Estimate recession speed of a galaxy from its distance. Enter distance, hubble constant in the fields above; the recession velocity, fraction of light speed are computed instantly and plotted on the chart so you can see how the answer changes.
Formula
Variables
- d — Distance (Mpc)
- H0 — Hubble constant (km/s/Mpc)
Worked example
With distance = 100 Mpc, hubble constant = 70 km/s/Mpc, the calculator gives recession velocity ≈ 7,000 km/s; fraction of light speed ≈ 0.02334949.
Frequently asked questions
What is the formula for the hubble's law calculation?
Recession velocity (km/s) = H0 × d. Fraction of light speed = [Recession velocity] / 299792.458. Here d is distance (Mpc), H0 is hubble constant (km/s/Mpc).
What inputs do I need for the hubble's law calculator?
You need distance in Mpc, hubble constant in km/s/Mpc. Each field is pre-filled with a typical example so you can see how the result responds as you edit the numbers.
How do I use this calculator?
Type values into the input fields. Results and the chart update instantly. Use Reset to restore the example values, Copy results to paste them elsewhere, or Share to copy a link that preserves your inputs.
Is the result exact?
Calculations use standard formulas and double-precision arithmetic, then display about seven significant figures. Real-world measurements carry uncertainty, so treat results as estimates unless your inputs are exact.