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r/Astronomy vs r/space

Side-by-side using public descriptions, members, growth and rule titles from SubMouse. Missing fields show as n/a. Adult communities are excluded.

Swap sides New comparison Related to r/Astronomy Related to r/space

Space news desk vs amateur astronomy hobby

r/space shares informative content on astrophysics, cosmology, space exploration, planetary science and astrobiology. r/Astronomy covers the amateur hobby and scientific study of celestial objects—pictures, identification, questions and telescope help show up in its rule titles.

Both have SubMouse pages (space about 28.0M, rank #16; Astronomy about 3.2M, rank #333). Activity samples are similar in tempo (roughly 27 vs 25 posts/day) but differ in mix: space leans links/text with Sunday-only images per its titles; Astronomy’s sample is more image-led.

Collected titles keep sensationalism and social links out of space, and structure Astronomy around pictures/videos, object ID, questions and telescope help. Bring mission and cosmology news to space; bring backyard observing and gear questions to Astronomy.

r/space: space/cosmology news; no sensationalism; images only Sunday UTC.
r/Astronomy: amateur observing; pictures, ID, questions, telescope help.
News vs hobby practice. Both have full SubMouse community pages.

Written comparison based on public descriptions and rule titles · updated 2026-11-06.

r/Astronomy

Astronomy

The amateur hobby of humanity since the dawn of time and scientific study of celestial objects.

Members: 3.2M
7-day growth: +1.5K
Posts/day: 25.2
Directory rank: #333
Created: Mar 28, 2008
Submissions: Text or links

Sample mix: images 48%, text posts 28%, galleries 11%

Topics: Space & Astronomy

Rule titles (short names we collected)

Pictures & Videos
Object Identification
Questions
Telescope Help
Content
Behavior
Sources
Repetition & Relevance
Misinformation & Pseudoscience
Minimum Karma
Post Types

Open r/Astronomy on SubMouse

About this community: r/Astronomy (#333, about 3.2 million) covers amateur astronomy and scientific study of celestial objects. Collected rules cover Pictures & Videos; Object Identification; Questions; Telescope Help. Sample ~25.2 ppd (168 posts). Sample mix: image:80, text:47, gallery:19, link:12.

r/space

/r/space: news, articles and discussion

Share & discuss informative content on: * Astrophysics * Cosmology * Space Exploration * Planetary Science * Astrobiology

Members: 28M
7-day growth: +2.7K
Posts/day: 26.9
Directory rank: #16
Created: Jan 26, 2008
Submissions: Text or links

Sample mix: links 38%, text posts 29%, images 21%

Topics: News, Science, Space & Astronomy

Rule titles (short names we collected)

Submissions must be related to Space/Cosmology
No sensationalist/misleading/unscientific content or titles
No spam/blogspam/paywalled/pirated content
No petitions/surveys/crowdfunding
No social media links
No duplicate or re-hosted content
Images are only allowed on Sunday UTC
No low-effort or meme images are permitted at any time.
If an image is not OC you must give credit to the original photographer.
No low-effort/meme/joke/troll/insult comments
No unscientific or anti-scientific comments
Straightforward questions belong in the Space Questions Thread

Open r/space on SubMouse

About this community: r/space ranks #16 on SubMouse’s SFW Top list (about 28.0 million subscribers in the directory). Catalogue framing: Share & discuss informative content on: * Astrophysics * Cosmology * Space Exploration * Planetary Science * Astrobiology Moderation themes that shape the room include: Submissions must be related to Space/Cosmology; No sensationalist/misleading/unscientific content or titles; No petitions/surveys/crowd…

Supported differences

Aspect	r/Astronomy	r/space
Public focus (from each community’s public description)	The amateur hobby of humanity since the dawn of time and scientific study of celestial objects.	Share & discuss informative content on: * Astrophysics * Cosmology * Space Exploration * Planetary Science * Astrobiology
Size r/space is larger in our directory (about 8.9×).	3.2M members	28M members
Posting activity (our sample)	25.2/day	26.9/day
Common post types in our sample	images 48%, text posts 28%, galleries 11%	links 38%, text posts 29%, images 21%
Topic tags on SubMouse	Space & Astronomy	News, Science, Space & Astronomy
Selected rule titles (short names we collected)	Pictures & Videos; Object Identification; Questions; Telescope Help; Content	Submissions must be related to Space/Cosmology; No sensationalist/misleading/unscientific content or titles; No spam/blogspam/paywalled/pirated content; No petitions/surveys/crowdfunding; No social media links

What they share

Shared SubMouse topics: Space & Astronomy

Rules and tone we can verify

space: must be related to Space/Cosmology; no sensationalist/unscientific titles; no spam/paywalls; no petitions/surveys; no social media links; no duplicates/rehosts; Images only on Sunday UTC. Astronomy collected short titles group Pictures & Videos; Object Identification; Questions; Telescope Help; Content; Behavior; Sources.

Where this comparison comes from

Public descriptions and member counts from SubMouse’s safe-for-work directory. Short titles only.

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 post types are shown where recent activity is available. Rule lines are short titles, not the full sidebar. Directory rank is listing order.

Comparisons we prepared

Hand-written explanations for pairs where the public descriptions and rules support a real distinction:

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r/suggestmeabook vs r/booksuggestions — Two recommendation rooms—similar job, different size and house rules.
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r/Art vs r/drawing — Serious art showcase with strict presentation rules versus a broader drawing practice room.
r/science vs r/askscience — Sharing new peer-reviewed research versus asking experts science questions.
r/explainlikeimfive vs r/NoStupidQuestions — Layperson explanations with strict answer rules versus a wider anonymous Q&A net.
r/personalfinance vs r/povertyfinance — Mainstream budgeting and investing help versus guidance aimed at financial hardship.
r/Games vs r/gaming — Newsy, informative games coverage versus a huge general gaming feed.
r/Coffee vs r/espresso — Wide coffee talk versus espresso-machine technique and gear.
r/photography vs r/itookapicture — Gear and technique discussion versus posting your own photos for critique.
r/dating_advice vs r/relationship_advice — Early dating situations versus advice on ongoing relationships between people.
r/hiking vs r/CampingandHiking — Day-hike photos and talk versus backpacking with overnight gear.
r/malefashionadvice vs r/femalefashionadvice — Parallel fashion-advice communities split by audience focus—not identical twins.
r/SkincareAddiction vs r/AsianBeauty — Science-leaning general skincare versus Asian beauty brands and routines.
r/Fitness vs r/bodyweightfitness — General gym-and-goals fitness discussion versus training with bodyweight progressions.
r/loseit vs r/Fitness — Sustainable weight-loss support versus general physical fitness goals and training.
r/DIY vs r/HomeImprovement — Show-your-work DIY projects versus text-only home improvement questions.
r/history vs r/AskHistorians — Casual history discussion and articles versus strictly moderated historical Q&A.
r/news vs r/worldnews — US-and-world news articles versus major world news that excludes US-internal stories.
r/Music vs r/listentothis — Broad music community posts versus discovery posts that stay under a popularity threshold.
r/writing vs r/WritingPrompts — Craft-of-writing discussion versus prompt-driven short stories and poems.
r/tipofmytongue vs r/whatisthisthing — Naming a half-remembered title or phrase versus identifying a mysterious physical object.
r/BuyItForLife vs r/Frugal — Durable long-life products versus everyday frugality and resourcefulness.
r/Parenting vs r/Mommit — All-parents child-rearing discussion versus a moms-only support room for the messier details.
r/LifeProTips vs r/YouShouldKnow — Actionable life tips versus facts framed as things you should know.
r/camping vs r/backpacking — Tent and campsite camping versus wilderness or travel backpacking with trip write-ups.
r/cscareerquestions vs r/learnprogramming — Tech career navigation versus learning to program in any language.
r/technology vs r/gadgets — Technology news and surrounding issues versus posts about a single gadget.
r/food vs r/EatCheapAndHealthy — Original food photography versus budget-friendly healthy recipes with text.
r/running vs r/AdvancedRunning — All-levels running discussion versus advanced training mindset and race tactics.
r/slowcooking vs r/Cooking — Crock-Pot style slow-cooker recipes versus general cooking discussion and recipes.
r/nba vs r/Basketball — NBA league news and discussion versus playing and watching basketball across leagues.
r/buildapc vs r/buildapcsales — Custom PC build planning advice versus PC-part deal links.
r/Breadit vs r/Baking — Homemade bread baking versus cakes, cookies, pies and general baking.
r/dogs vs r/Dogtraining — Responsible dog ownership discussion versus dedicated training and behavior help.
r/malefashionadvice vs r/frugalmalefashion — Men’s style advice and outfits versus male-fashion deals and coupons.
r/SkincareAddiction vs r/30PlusSkinCare — General science-leaning skincare versus skincare discussion aimed at people over 30.
r/OutOfTheLoop vs r/NoStupidQuestions — Catching up on a current meme or news loop versus asking any straightforward question.
r/space vs r/Astronomy — Space science and exploration news versus amateur astronomy observing and gear.
r/relationships vs r/relationship_advice — Structured interpersonal advice with question-type rules versus a high-volume room for specific situations.
r/gaming vs r/pcgaming — Broad gaming posts and memes-with-limits versus PC gaming news and discussion.
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r/webdev vs r/javascript — Front- and back-end web development discussion versus JavaScript language and project talk.
r/Frugal vs r/povertyfinance — Waste-less frugal living habits versus money help for people struggling financially.
r/homestead vs r/gardening — Self-sufficiency, livestock and country life versus plant growing and care.
r/woodworking vs r/DIY — Woodworking and furniture making versus all kinds of DIY projects and repairs.
r/boardgames vs r/rpg — Modern board games news and discussion versus tabletop roleplaying games.
r/keto vs r/loseit — Ketogenic low-carb eating versus weight loss through any sustainable method.
r/changemyview vs r/unpopularopinion — Willingness-to-revise debate versus broadcasting an unpopular take.
r/Android vs r/iphone — Android platform news/tips versus iPhone enthusiast discussion.
r/cars vs r/MechanicAdvice — Enthusiast news and projects versus repair troubleshooting help.
r/Python vs r/learnpython — Python language hub versus learner Q&A helpdesk.
r/Jokes vs r/dadjokes — General joke threads versus dad-joke puns and groaners.
r/mildlyinteresting vs r/interestingasfuck — Quietly notable original photos versus content that aims to be truly striking.
r/Futurology vs r/technology — Evidence-leaning futures discussion versus technology news and surrounding issues.
r/movies vs r/television — Film news and discussion versus scripted television programming talk.
r/LifeProTips vs r/lifehacks — Actionable LPT-format advice versus uncommon physical-style life hacks.
r/AmItheAsshole vs r/relationship_advice — Moral-judgment verdicts on a conflict versus specific advice for a real relationship situation.
r/anime vs r/manga — Animated anime discussion versus manga (and manhwa/manhua) reading talk.
r/dating vs r/dating_advice — General dating discussion and venting versus situation-specific dating advice.
r/investing vs r/stocks — Broader investing discussion versus ticker- and market-focused stock talk.
r/AskMen vs r/AskWomen — Questions aimed at men’s experiences versus questions aimed at women’s perspectives.
r/MakeupAddiction vs r/SkincareAddiction — Makeup looks, products and questions versus science-leaning skincare routines.
r/streetwear vs r/malefashionadvice — Streetwear fit photos and discussion versus broader men’s fashion advice.
r/offmychest vs r/TrueOffMyChest — Supportive emotional sharing versus a stricter personal off-my-chest format.
r/hockey vs r/nhl — All-hockey discussion including leagues beyond the NHL versus NHL-focused news and talk.
r/astrophotography vs r/Astronomy — Amateur sky photos with gear notes versus broader astronomy discussion and learning.
r/CryptoCurrency vs r/Bitcoin — Multi-coin crypto news and discussion versus Bitcoin-only focus.
r/MadeMeSmile vs r/UpliftingNews — Feel-good images and videos versus positive news article links.
r/xxfitness vs r/Fitness — Fitness discussion centered on women and gender-diverse lifters versus the general Fitness wiki room.
r/smallbusiness vs r/Entrepreneur — Q&A for owning a small business versus broader entrepreneurship discussion.
r/Mommit vs r/daddit — Moms’ parenting support versus dads’ parenting support.
r/Damnthatsinteresting vs r/interestingasfuck — High-interest media shares versus “interesting as fuck” media shares—overlapping curiosity feeds with different rule bars.
r/getdisciplined vs r/productivity — Self-discipline accountability and methods versus productivity tips and tools.
r/financialindependence vs r/personalfinance — FIRE and financial independence goals versus everyday personal-finance budgeting and debt help.
r/learnart vs r/Art — Practice, feedback and learning resources versus a serious gallery of finished art.
r/soccer vs r/PremierLeague — Global football news and discussion versus English Premier League focus.
r/nfl vs r/fantasyfootball — NFL news and game talk versus fantasy-football strategy and roster advice.
r/sidehustle vs r/Entrepreneur — Extra income beside a full-time job versus broader entrepreneurship and startup talk.
r/careerguidance vs r/jobs — Career-path questions and advice versus job-search, interview and workplace threads.
r/legaladvice vs r/law — Personal legal questions versus news and discussion of the legal profession.
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r/tea vs r/Coffee — Camellia sinensis and tea culture discussion versus coffee brewing, gear and community talk.
r/Guitar vs r/piano — Guitar gear, lessons and play videos versus piano practice, digital-piano help and performances.
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r/femalelivingspace vs r/malelivingspace — Living-space tours and décor help framed for women versus living-space tours and advice framed for men.
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r/Physics vs r/AskPhysics — Physics community for physicists and students versus a dedicated ask-a-physics-question room.
r/InteriorDesign vs r/architecture — Interior design and interior architecture of spaces versus architecture of buildings and practice.
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r/AskCulinary vs r/Cooking — Single-answer culinary technique questions versus broader cooking discussion and recipes.
r/DIY vs r/somethingimade — How-to DIY help and home projects versus showcasing finished handmade crafts you made.
r/homeautomation vs r/smarthome — DIY home-automation projects and setups versus smart-home product and platform help.
r/TrueCrime vs r/UnresolvedMysteries — True-crime discussion and media versus unresolved cases, disappearances and open mysteries.
r/comics vs r/comicbooks — Print comics, strips and webcomics (including OC) versus comic-book fandom discussion.
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r/Documentaries vs r/movies — Free documentary links and discussion versus general film news and movie talk.
r/nutrition vs r/loseit — Nutrition science discussion versus sustainable weight-loss community support.
r/graphic_design vs r/Design — Graphic-design education and critique versus broader design discussion and work shares.
r/blender vs r/3Dmodeling — Blender-specific showcase and help versus general 3D modeling across tools.
r/Jazz vs r/classicalmusic — Jazz listening and discussion versus classical music discussion and recommendations.
r/PersonalFinanceCanada vs r/personalfinance — Canada-specific personal finance versus the large US-leaning personal finance community.
r/Watercolor vs r/painting — Watercolor-specific painting and critique versus general painting gallery discussion.
r/simpleliving vs r/minimalism — Simple-living lifestyle discussion versus minimalism as intentional simplicity.
r/flexibility vs r/yoga — Stretching and mobility progress versus yoga practice and lifestyle discussion.
r/ThriftStoreHauls vs r/Frugal — Showing thrift and secondhand finds versus frugal living strategy discussion.
r/FrugalFemaleFashion vs r/femalefashionadvice — Budget women’s fashion deals and discussion versus broader female fashion advice.
r/Fantasy vs r/worldbuilding — Speculative-fiction reading and fandom discussion versus creating fictional worlds.
r/DigitalPainting vs r/drawing — Critique-focused digital painting versus general drawing shares across media.
r/oilpainting vs r/painting — Real oil-paint shares and technique versus general painting gallery discussion.
r/skiing vs r/snowboarding — Alpine skiing discussion versus snowboarding (Shreddit) gear, riding and travel questions.
r/startrek vs r/StarWars — Welcoming Star Trek discussion versus the large unofficial Star Wars franchise community.
r/formula1 vs r/NASCAR — Independent Formula 1 race discussion versus NASCAR news and race-day threads.
r/Meditation vs r/Mindfulness — Meditation practice experiences versus mindfulness as everyday awareness.
r/travel vs r/TravelHacks — General travel questions and trip reports versus cheap-travel tips and logistics hacks.
r/grilling vs r/smoking — Cooking over direct fire versus low-and-slow wood-smoke flavor techniques.
r/mlb vs r/baseball — Major League Baseball–only news and discussion versus broader baseball covering other leagues too.
r/Bitcoin vs r/BitcoinBeginners — Main Bitcoin discussion versus a beginners-only questions room with strict anti-scam norms.
r/todayilearned vs r/explainlikeimfive — Sourced “today I learned” fact posts versus simplified how-it-works explanations.
r/IAmA vs r/AMA — Large Ask Me Anything interview community versus a smaller general AMA room.
r/politics vs r/PoliticalDiscussion — High-volume political news links versus civility-focused political discussion threads.
r/DnD vs r/rpg — Dungeons & Dragons–specific posts versus broader tabletop RPG discussion across systems.
r/truegaming vs r/ShouldIbuythisgame — In-depth game discussion versus platform-tagged “should I buy this?” purchase advice.
r/TooAfraidToAsk vs r/NoStupidQuestions — Sensitive questions people hesitate to ask versus a huge anonymous general Q&A room.
r/options vs r/investing — Exchange-traded options strategies versus broader investing discussion (not personal-finance advice).
r/CreditCards vs r/personalfinance — Credit-card product discussion versus broad personal-finance budgeting and planning.
r/crochet vs r/sewing — Crochet finished objects and WIPs versus sewing projects, alterations and machine questions.
r/NintendoSwitch vs r/nintendo — Nintendo Switch (and Switch 2) news and questions versus broader Nintendo past-present-future discussion.
r/cycling vs r/bicycling — Text-only bike discussion versus a photo-friendly community for riders of every level.
r/PS5 vs r/playstation — PS5 news and discussion hub versus the casual PlayStation community for images, trophies and chat.
r/europe vs r/AskEurope — Link-based European news and data versus text questions to Europeans about their countries.
r/Cooking vs r/recipes — Text cooking discussion and questions versus a recipe-sharing feed with a required post format.
r/Cooking vs r/cookingforbeginners — General cooking discussion versus a no-gatekeeping room for people learning to cook.
r/Entrepreneur vs r/startups — Business-building discussion of every size versus companies designed to scale rapidly.
r/japan vs r/JapanTravel — General Japan news and discussion (no tourist posts) versus trip planning and travel tips for Japan.
r/marvelstudios vs r/Marvel — Marvel Studios films, series and the MCU versus Marvel Comics and its characters.
r/apple vs r/mac — Discussion of Apple as a whole (no tech support) versus a Mac-only community that takes questions.
r/legaladvice vs r/LegalAdviceUK — Simple legal questions (location required) versus UK-only legal triage for England, Wales, Scotland and Northern Ireland.
r/travel vs r/Shoestring — General travel questions and trip reports versus budget travel, cheap destinations and deals.
r/AskUK vs r/unitedkingdom — Questions about UK life and culture versus UK news, politics and society links.
r/stocks vs r/StockMarket — Serious stock and company discussion with position disclosure versus short- and mid-term trade ideas and market commentary.
r/pokemon vs r/pokemongo — Pokémon across games, shows, cards and art versus Pokémon GO, Niantic’s mobile game.
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r/movies vs r/MovieSuggestions — Film news and discussion versus a room for requesting and giving movie recommendations.
r/college vs r/ApplyingToCollege — College life once you’re there versus admissions questions before you get in.

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