AAVSO’s Annual Campaign
Donate Now to Support Variable Star Education.
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https://www.aavso.org/donate-now
They Might Be Hypergiants
AAVSO data has helped unveil the mysteries of Rho Cas and stars like it.
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https://www.aavso.org/blog/they-might-be-hypergiants
A Universe of Opportunity: The Future of Small Telescope Science in the LSST Era
Each time a major sky survey comes online, the inevitable question arises: “Is this the end of amateur astronomy?”
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https://www.aavso.org/blog/future-of-small-telescope-science
Discover the AAVSO
An international community
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/welcome
Welcome to the conversation.
We are excited to announce a transition to a new forum system. The new system is modern, faster, and easier-to-use.
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https://forums.aavso.org/

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The mission of the AAVSO is to enable anyone, anywhere to participate in scientific discovery through variable star astronomy. 

Resources

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(VSX) Variable Star Index
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Pick a Star

Plot a light curve
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The Journal of the AAVSO
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Data
Submit and Access Data
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Telescope
Tools and Observer Resources
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Observing Sections
Observing Sections
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Education
Education
CHOICE Courses, Manuals, Videos
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AAVSO In the Press
AAVSO In the Press
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Membership and Support
Membership and Support
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The AAVSO is an equal opportunity and discrimination / harassment free environment. 
Please read our policies HERE

AAVSO at a Glance

Variable Star Observations in Database:

7 8 , 2 4 2 , 3 9 8 and Counting ...

Last Observation Received:

37 min 2 sec ago by CCHD - CHARLES CYNAMON (US)

V0899 LYR   Dec 19.099   12.714V

Plot V0899 LYR light curve

JAAVSO Volume 53, Number 2, December 2025, print version now available
Dec 17
JAAVSO Volume 53 Number 2, 2025 is published
Dec 15
Director’s Report for 2025-Q2
Dec 2
New User Profiles, Settings, and Search
Oct 22
New Data Usage Guidelines
Oct 7
News Archives

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