endoMoons is a web application for visuallizing the various planetary systems of our Solar System from a top-down perspective. It is designed to help with the conceptualization of our solar system since astronomical diameters and distances are often difficult to comprehend. Relative sizes and distances of objects and orbits are always preserved when "zooming", and are increased or decreased by factors of 2 when scaling separately.

Pluto, while no longer considered a planet, is still a system, and is included along with Mercury and Venus (which have no moons and aren't really systems). All moons with a longest dimension of at least 18 kilometers are displayed in addition to Deimos (of Mars) and Styx (of Pluto). Non-spherical moons include all those with diameters less than 396 km and Proteus (of Neptune, which is large enough to be spherical but isn't). These moons, however, are still displayed as spheres.

The name endoMoons is derived from the term exomoon which refers to a natural satellite outside our own Solar System, so while technically the prefix endo- ("within") is the opposite of exo- ("outside"), you may sound silly saying it in an astronomical circle of peers.

I also built a Scale Solar System web application (as seen from edge on) that you may find useful. If space is your shtick, I wrote some books for iPad that you might like. Contact me via @wetjosh and read my thoughts on my blog.

Note: endoMoons should be considered an educational tool. While the semi-major axes displayed here are extremely accurate, other variables like orbital eccentricities, inclinations, angular positions (all moons start lined up at the top), etc. are not taken into account.