Using in Publications

When using ASAS-SN light curves in publications cite: Shappee et al. (2014) and either: (i) The ASAS-SN Catalog of Variable Stars I: Jayasinghe et al. (2018a) or (ii) The ASAS-SN Catalog of Variable Stars II: Jayasinghe et al. (2018b) , (iii) The ASAS-SN Catalog of Variable Stars III: Jayasinghe et al. (2019b) , (iv) The ASAS-SN Catalog of Variable Stars V: Jayasinghe et al. (2020) , or (v) The ASAS-SN Catalog of Variable Stars IX: Jayasinghe et al. (2021).

Welcome to Citizen ASAS-SN! Go to Citizen ASAS-SN


Citizen ASAS-SN shows you "light curves" obtained using the All-Sky Automated Survey for SuperNovae (ASAS-SN). ASAS-SN is currently the only survey to monitor the entire visible sky every night. Over the duration of our project, we have collected close to ~1 Petabyte of image data. ASAS-SN currently monitors the entire night sky in the optical wavelength range. To make our observations scientifically useful, we limit the photons that we capture by using a filter. A filter selectively transmits light with specific wavelengths. ASAS-SN currently uses Sloan g-band filters which are "teal" colored, with an effective central wavelength of 480 nm, and a FWHM of 141 nm. Previously, we used Johnson V-band filters which are "green" colored, with an effective central wavelength of 551 nm, and a FWHM of 88 nm. A light curve is a record of the brightness observations of a given star made over the years. Light curves are used to understand how a star's brightness changes over time (or not). The brightness of most stars remain constant, however a small fraction show brightness fluctuations. These are the "variable stars". ASAS-SN light curves enable the discovery and characterization of variable stars, whose brightness fluctuates over time. After analyzing the archival V-band light curves of over 60 million stars through machine learning techniques, we have discovered over ~220,000 new variable stars in the Milky Way and cataloged over ~600,000 in total. However, we have since overhauled our network of telescopes and we can now monitor about 100 million Milky Way stars in the newer g-band ASAS-SN data. Compared to our archival V-band data, this new data set is especially promising for the discovery and characterization of new variable stars. With the g-band data, we have made several improvements over our initial V-band data set. We are now looking at fainter objects in the g-band, and have improved our rate of data collection from ~2-3 days in the V-band to ~20 hours in the g-band, allowing us to study and discover more variable stars in greater detail than we did before.

Gallery

Citizen ASAS-SN DR1


ASAS-SN’s citizen science project is called Citizen ASAS-SN, and it primarily focuses on the classification of g-band light curves. Since this project launched, thousands of volunteers worldwide helped classify variable star candidates in our new g-band data by analyzing their light curves. The ASAS-SN team would like to give a special thanks to these volunteers, and below we recognize some of our the most active users.

Contributers Download Catalog and Light Curves