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Guide to Chi Cygni

A Mira type variable in the 'neck' of the Swan, that has a brightness range of over 10 magnitudes.

In May 2013, Chi Cygni reached an impressive magnitude of 3.8 when at maximum.

2014 brought a marked contrast with the early July maximum only reaching about magnitude 6.4 - possibly the faintest maximum since the discovery of the brightness variations of chi Cygni in the late 17th century. The 2015 maximum was somewhat brighter, peaking at around magnitude 4.4, whereas that of 2016 was fairly "normal" at around mag 5.0.

Extreme brightness range 3.4 - 14.2
More typical range 5.1 - 13.4
Period of variation 407  days  (approx 13.5 months)
Frequency of observation Worth checking a few times per month
Observe using naked eye for the brighter maxima ; binoculars when fainter ; a telescope to follow it all the way down to minimum
Visibility Can be observed all year round, but is only visible in the morning sky from mid January to April
Upcoming maxima early November 2017, early December 2018

The finder charts which follow show the location of chi Cygni.

The first shows the wider view and some of the brighter comparison stars that are suitable for naked eye observations.

This second chart shows the area around chi Cygni in more detail and labels several comparison stars suitable for use when observing using binoculars.