115th Annual Meeting Registration is Now Open
Join us in Santa Fe, NM Nov. 7th and 8th
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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 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 vision of the AAVSO is to become the leading platform where people of all ages and backgrounds learn about and participate in scientific astronomy.

Resources

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(VSX) Variable Star Index
https://vsx.aavso.org/

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:

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

Last Observation Received:

8 min 28 sec ago by HMB - Franz-Josef (Josch) Hambsch (BE)

ZTF J225704.95+623822.9   Jun 24.0906   15.727V

Plot ZTF J225704.95+623822.9 light curve

JAAVSO Volume 54, Number 1, 2026 is published
Jun 15
Building for the Future: AAVSO Expands Staff and Scientific Capacity
Jun 15
Joanna DiStefano
Jun 3
AAVSO 115th Annual Meeting | November 7–8, 2026
May 20
A wonderful visual discovery - Stubbings V1
Feb 23
News Archives

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