About r/space
r/space is one of the largest safe-for-work communities on Reddit, ranked #16 on SubMouse with 27,990,867 subscribers.
In its own words:
Share & discuss informative content on: * Astrophysics * Cosmology * Space Exploration * Planetary Science * Astrobiology
The community was created on Jan 26, 2008, which makes it 18 years old. Since Oct 19, 2026, it has gained 3,894 subscribers (+0.01%). It sits just behind r/Jokes (#15) and ahead of r/DIY (#17) in our ranking.
How to join
Open reddit.com/r/space and press “Join”. Read the community rules in the sidebar before you post: every subreddit is run by its own volunteer moderators.
Stats from public data (data updated Oct 29, 2026). SubMouse is an independent directory and is not affiliated with Reddit or the moderators of r/space.