The relative sizes of the stars and planets

My colleague sent me this link which shows the relative sizes of the planets in our solar system and some of the brightest stars in the sky. Not only does it make the Earth look small, it makes our sun look small. Pretty amazing!

Just for fun I decided to create an interactive GeoGebra applet illustrating the relative sizes of these objects. I also threw in the orbits of the planets in the solar system (assuming they were circular).

I got all of my values from Wikipedia. Interestingly, it shows Betelgeuse (radius 936 times the radius of our sun) to be larger than Antares (800x). But my friend’s link has them switched. I have no idea if this is within the margin of error.

According to Wikipedia, the largest known star is VY Canis Majoris, the radius of which is believe to be somewhere around 2000 times the radius of the sun!


  1. drj11 says:

    xkcd shows the relative sizes of the planets’ gravity wells:

    What no Kuiper belt objects?

    1. Yeah, I love that xkcd comic! Kuiper belt objects… maybe in the 2.0 version of the applet :-)

    2. sherifffruitfly I’ll send you a reply by email.

  2. sherifffruitfly says:


    For someone who is already very familiar with Lakatos’ Proofs and Refutations, how much value is added by reading your Euler’s Gem book?

Comments are closed.