Webinar | Recognizing AAVSO’s All Stars
Join us as we celebrate the collective achievements of our community.
Slider Link
https://us02web.zoom.us/webinar/register/6017345582722/WN_RlCkYTyIQi-NKecusrjdOQ
Donate to the AAVSO!
Your support will provide opportunities that will influence generations of observers.
Slider Link
https://www.aavso.org/annual-campaigns/2025-annual-campaign?utm_source=slider&utm_medium=web&utm_campaign=ac25&utm_content=hps241112
RW Cephei, King of Kings
The physical processes behind a hypergiant’s “great dimming” may have been unlocked by high-resolution imagery and a century’s worth of AAVSO observations
Slider Link
https://www.aavso.org/blog/rw-cephei
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/

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:

6 6 , 0 6 2 , 4 4 2 and Counting ...

Last Observation Received:

15 min 7 sec ago by HDAE - David Heinonen (SE)

R CrB   Jan 15.2181   5.8Vis.

Plot R CrB light curve

Solar Section Looks Back to the Future
Dec 23
Winter 2024 Visual Observing Challenge
Dec 19
JAAVSO Volume 52 Number 2, 2024 is published
Dec 15
RW Cephei, a King of Kings
Dec 11
Board Election Results
Nov 19
News Archives

Our Stellar Partners


orange circle with with snake next to the words "The Astropy Project"

Diffraction Limited logo of a swirled circle with text: Diffraction: Astronomy + Scientific Imaging SolutionsIm

Chroma Technology logo: the word chroma goes through a bright rainbow-colored hoop

Black outline of an intricately dressed being with accentuated features

Unistellar

Boyce Astro Logo

Text reads DC-3 Dreams Observatory Operating Systems

Text reads "Sky & Telescope" with the ampersand in a circle.

NSF

NASA Logo