[dougdimmadome]

I like this. It really helps illustrate that how long it takes to get to Mars can vary hugely depending on when you leave Earth.

My kids learned in school (during the 5 minutes of the year they spent talking about the solar system) that Venus is closer to Earth than Mars, but I had to use a diagram like this to explain that that's only sometimes true

kind of limiting that you can only go back and forward in time one month though. I would love a slider, a play button

[vundercind]

The free (FOSS, I believe) program Celestia is excellent for showing kids that kind of thing.

It’s also lua-scriptable. I once created a “tour of the solar system” script that worked like a presentation (hit a button to advance to the next view) for my wife to use in her classroom, in an afternoon, never having scripted the program or written Lua before. Did a top-down view with orbital tracks, zoomed to planets, did side-by-side size comparisons, all kinds of stuff. Not hard to use, very cool. Or you can just click around the UI and use keyboard shortcuts to demonstrate quite a bit of stuff.

[grvbck]

If you're on iOS, there's an app called Solar Walk that might be fun to play around with.

If you want orbits and a slider, there's <https://www.pbslearningmedia.org/resource/buac20-sci-ess-wwt...>