A short, curated guide — not an automatic related dump. Figures come from SubMouse's safe-for-work directory when we have them.
r/Astronomy (about 3.2M members, directory rank #333) covers the amateur hobby and scientific study of celestial objects — pictures, identification, questions and telescope help. Spaceflight and cosmology news, and photo-first astrophotography, are neighbouring but different.
See also space vs Astronomy on SubMouse.
Stay on Astronomy for observing, gear and celestial ID. Use space for astrophysics and exploration news, and astrophotography when the craft is imaging the sky.
r/Astronomy — Astronomy
The amateur hobby of humanity since the dawn of time and scientific study of celestial objects.
/r/space: news, articles and discussion
When to choose it: Astrophysics, cosmology, space exploration and planetary science news.
Why it is here: Paired on space vs Astronomy; shared Space & Astronomy topic. Public description covers those science/exploration topics (about 28.0M members, rank #16).
How it differs from r/Astronomy: News and exploration versus amateur observing practice.
Amateur Astrophotography
When to choose it: Photographing the night sky and imaging technique.
Why it is here: Listed among Astronomy's directory related names. Public description: celebrates amateur astrophotography and sharing images (about 2.6M members, rank #422).
How it differs from r/Astronomy: Imaging technique versus general astronomy hobby talk.
Run the automatic finder for r/Astronomy (results are matched from our directory; that page is not indexed): Find related to r/Astronomy.
Members and public descriptions come from SubMouse's safe-for-work directory (as of 2026-11-02 UTC); 7-day growth measured from 2026-10-26. Posts/day and culture claims appear only when we have them — missing fields stay n/a. Directory rank is listing order. Communities outside the published Top 100 open in the info tool instead of a full community page. Guide updated 2026-11-07.