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Sun, 31 Jul 2016 - Chi Cygni now visible in binoculars

The Mira type variable Chi Cygni has produced some very interesting behaviour in recent years with two maxima being much brighter than the average and the intervening one being unusually faint, as can be seen in this light curve.

The next maximum is due in September. However, with Chi Cygni being a Mira type variable, we can neither predict its peak brightness in advance or predict the date (or even the week) when this will occur. Its just a case of making a regular check on its brightness.

The latest observations of Chi Cygni from late July place it at about magnitude 8.8, so within the brightness limits of common binocular sizes from reasonably dark observing sites. Previous experience would suggest that it will brighten to around mag 8.0, then possibly pause and then put in a brightness surge of over a magnitude in a week ... but you can never be sure with a Mira type variable!

You can follow the brightness changes of Chi Cygni over the coming weeks using this finder chart, which has north at the top

More information about Chi Cygni, including a finder chart showing the wider area around Chi Cygni, can be found at


Added by: Tracie Heywood