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/
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
Webinar | SIGs in the Spotlight
Attend to learn about exoplanets, solar observing & YSOs. | June 7 @ 2:00pm ET on Zoom.
Slider Link
https://us02web.zoom.us/webinar/register/6117452724173/WN_llJHm6zkT1a1wpK0WLjBCg
Announcing: AAVSO Annual Meeting in Portland Oregon
Our Annual Meeting will be held November 1-2 at the Oregon Museum of Science & Industry.
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
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/
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
Webinar | SIGs in the Spotlight
Attend to learn about exoplanets, solar observing & YSOs. | June 7 @ 2:00pm ET on Zoom.
Slider Link
https://us02web.zoom.us/webinar/register/6117452724173/WN_llJHm6zkT1a1wpK0WLjBCg
Announcing: AAVSO Annual Meeting in Portland Oregon
Our Annual Meeting will be held November 1-2 at the Oregon Museum of Science & Industry.
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
Discover the AAVSO
An international community
Slider Link
/welcome

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
/vsx

Pick a Star

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

6 9 , 5 0 7 , 3 0 9 and Counting ...

Last Observation Received:

34 min 19 sec ago by LEDE - Edward Lyons (IE)

T CrB   May 25.0771   10.1Vis.

Plot T CrB light curve

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
New Data Search and Submit Applications
Mar 6
News Archives

Our Stellar Partners


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