Now begins our seventeenth topic challenge!
Dates: 28 September - 12 October
We've seen a lot of questions here about planets and the people on them, but the existence or nonexistence of moons is also a very important factor to the planet, influencing factors such as tides.
Remember to use this tag if you're asking a question as part of the challenge.
In two weeks, we'll announce the stats for users who asked and answered questions using the tag. If you have questions, see the original post or ask in chat.
Propose new topics here: What should be the subjects of our fortnightly topic challenges?