Total Impact
74M+ Submitted Observations
10.4M Variable Stars
Year In Review
38 Observing Campaigns
282 Peer-Reviewed Papers
Read the 2025 Annual Report →
Getting Started with Observing
You don’t need any special equipment to start observing – just your eyes!
Contribute Data
Submit your observations and join thousands of citizen scientists advancing research.
Find Stars to Observe
Discover which variable stars you can watch tonight from your location.
Learn Observing
Master the basics of variable star observation through our simple, step-by-step guides.
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