Announcing the 2024 Fundraising Campaign
Every contribution helps the AAVSO achieve its mission.
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https://www.aavso.org/2024-annual-fundraising-campaign
Target Tool Has a New Home
Click Here to Learn More
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https://www.aavso.org/target-tool-has-new-home
The European Space Agency wants your help!
.
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https://www.esa.int/Enabling_Support/Preparing_for_the_Future/Space_for_Earth/Amateur_astronomers_needed_help_classify_stars_with_Gaia_s_data
La Ciencia del Cielo para Principiantes
Seminarios web de astronomia gratis en espanol
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/2023-seminarios-web
Discover the AAVSO
an international community
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/welcome
Happy 100th Birthday: M31-V1!
How Edwin Hubble's discovery of the first Cepheid variable in M31 expanded our view of the universe.
Slider Link
/blog/shattering-shapleys-universe
Webinar: HST Observations of AB Aur
Learn how to contribute to AAVSO's AB Aur campaign. Art: NASA, ESA, Joseph Olmsted (STScI)

Slider Link
https://us02web.zoom.us/webinar/register/3016999884842/WN_Vr3GfhiDRMSrQpGyvrzUlA
observe in the city
Register for December's free webinar.
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https://us02web.zoom.us/webinar/register/6817001574899/WN_8YGLAey-S8GrcKZnAhg8pw

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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
/index.php/vsx

Pick a Star

Plot a light curve
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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 Press
AAVSO In 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 0 , 7 0 4 , 2 9 2 and Counting ...

Last Observation Received:

4 min 55 sec ago by KBE - Bradley Kulbaba (CA)

R Leo   Mar 20.276   10.2Vis.

Plot R Leo light curve

Alert Notice 843: Photometry of R Mon, UX Ori, CO Ori, RR Tau, and RY Tau needed now in support of spectroscopic campaign
Nov 21
Cleaning Up VSD
Nov 16
Alert Notice 842: AB Aur monitoring requested for HST observations
Nov 15
Alert Notice 841: VY Scl coverage needed now for HST ToO observations
Nov 13
Alert Notice 840: Anticipated primary eclipse of b Per centered on November 28 2023 UT
Nov 10
News Archives

Our Stellar Partners


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Unistellar

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NSF

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