ccd observing

CCD Photometry Guide in Greek

Thanks to another great volunteer effort by Stelios Kleidis, we now have available a full Greek translation of the AAVSO Guide to CCD Photometry! If you know of anyone who would benefit from this translation, please feel free to spread the word and share the link.

If you would like to volunteer your time to translate this Guide into your native language, please contact Sara Beck (sara (at)

SN 2011fe

Welcome to the AAVSO's special webpage devoted to SN 2011fe!

SN 2011fe is the brightest supernova as seen from Earth in nearly 20 years.  It's a rare event that astronomers around the world are excited about -- it's not only a beautiful spectacle, it may also teach us new things about supernovae and the universe that we live in.  Here you'll find information on what SN 2011fe is, why astronomers around the world are watching it, and most importantly, how you can make your own observations and help create a scientific record of this supernova!

Note on automatic rejection of low signal-to-noise data

Note on Automatic Rejection of Low Signal-to-noise Data

The AAVSO has a policy in place that states positive observations having errors equal to or greater than 1.0 magnitudes are not accepted as is. For a given measurement, an error of 1.0 magnitude is equivalent to a signal-to-noise ratio of 1, meaning that the purported signal is indistinguishable from the average noise fluctuation in the data and statistically is not a significant detection.