Discover the AAVSO
An international community
Slider Link
/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
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
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
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?
Slider Link
https://www.aavso.org/114/abstracts
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?”
Slider Link
https://www.aavso.org/blog/future-of-small-telescope-science
Discover the AAVSO
An international community
Slider Link
/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
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
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
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?
Slider Link
https://www.aavso.org/114/abstracts
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?”
Slider Link
https://www.aavso.org/blog/future-of-small-telescope-science

old logo

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

Resources

VSX Logo
(VSX) Variable Star Index
/index.php/vsx

Pick a Star

Plot a light curve
jaavso
The Journal of the AAVSO
/index.php/apps/jaavso
Data
Submit and Access Data
/index.php/databases
Telescope
Tools and Observer Resources
/index.php/observers
Observing Sections
Observing Sections
/index.php/observing-sections
Education
Education
CHOICE Courses, Manuals, Videos
/index.php/education
AAVSO In the Press
AAVSO In the Press
/index.php/press
Membership and Support
Membership and Support
/index.php/join-aavso

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 0 , 9 4 8 , 7 5 0 and Counting ...

Last Observation Received:

2 min 46 sec ago by KJEA - Jeffrey Kasoff (US)

ALF CYG   Jul 23.2521   1.278V

Plot ALF CYG light curve

JAAVSO Volume 53, Number 1, June 2025, print version now available
Jul 2
A Universe of Opportunity: The Future of Small Telescope Science in the LSST Era
Jul 1
Remark-O-Matic
Jun 25
JAAVSO Volume 53 Number 1, 2025 is published
Jun 15
WebObs 2.0: A New Photometric Data Submission Application
May 23
News Archives

Our Stellar Partners


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