Annual Meeting Registration Open
Join us at the Oregon Museum of Science and Industry on November 1-2.
Slider Link
https://www.aavso.org/114
Webinar | SIGs in the Spotlight
Attend to learn about eclipsing binaries, instrumentation & short period pulsating variables. | July 12 @ 2:00pm ET on Zoom.
Slider Link
https://us02web.zoom.us/webinar/register/8317483691879/WN_Jm_SQh1lSwi18lbC9Ht1og
They Might Be Hypergiants
AAVSO data has helped unveil the mysteries of Rho Cas and stars like it.
Slider Link
https://www.aavso.org/blog/they-might-be-hypergiants
Call for Abstracts
Interested in giving an in-person or remote oral presentation?
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https://www.aavso.org/114/abstracts
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.
Slider Link
https://forums.aavso.org/
Webinar | SIGs in the Spotlight
Learn about Eclipsing Binaries, Instrumentation & Equipment, and Short Period Pulsating Variables. | July 12 @ 2:00pm ET on Zoom.
Slider Link
https://us02web.zoom.us/webinar/register/8317483691879/WN_Jm_SQh1lSwi18lbC9Ht1og
Director’s Report | 2025 Q1
Updates on the Annual Meeting, website relaunch, strategic plan, financial overview, and more.
Slider Link
https://www.aavso.org/blog/directors-report-2025-q1
Call for Nominations
Submit your recommendations for recipients of the Merit Award and the William Tyler Olcott Distinguished Service Award.
Slider Link
https://docs.google.com/forms/d/e/1FAIpQLSdF6dmZGDOzE5nzlhjMqOn5DCoYrinW-bIp8gnB1jcaosJe_A/viewform?usp=header

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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
/vsx

Pick a Star

Plot a light curve
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The Journal of the AAVSO
/apps/jaavso
Data
Submit and Access Data
/databases
Telescope
Tools and Observer Resources
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Observing Sections
Observing Sections
/observing-sections
Education
Education
CHOICE Courses, Manuals, Videos
/education
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:

6 9 , 9 0 2 , 5 9 6 and Counting ...

Last Observation Received:

54 sec ago by CTIA - Tiziano Colombo (IT)

alf sco   Jun 17.9215   1.1V

Plot alf sco light curve

JAAVSO Volume 53 Number 1, 2025 is published
Jun 15
WebObs 2.0: A New Photometric Data Submission Application
May 23
Changes on the Horizon
May 20
Director’s Report for 2025-Q1
May 5
They Might Be Hypergiants
May 1
News Archives

Our Stellar Partners


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