This
is a unique-appearing open cluster that is often overshadowed by the
wealth of other clusters in the region. The primary stars of
the main cluster form a diamond-shaped outline with a trail of
similar stars extending off one of the four corners. To my eye
this appears strikingly like a flying kite with tail. Others
have seen a heart-shaped balloon. Walter Scott Houston
nicknamed NGC 1664 the the "4-H cluster because it had the
appearance of a four-leaf clover that most farm children recognize
as the symbol of the 4-H club."
Scotty also said that
NGC 1664 was "difficult in my 4-inch Clark refractor" and
that the "familiar outlines of an open cluster emerge into view
with a telescope somewhere between 4- and 6-inch aperture."
The majority of the stars that form the recognizable asterism are
10th magnitude. I was quite struck by how similar the
stars in the asterism appear in both magnitude and color. In
my 18-inch myriad fainter stars appear in the background, making for
a very pleasing sight.
Note that the image to
the right has north up and east to the left in order to better show
the "kite" asterism. To match it to the diagram
below it must be rotated 180 degrees.

The field in an 6-inch at
50x. North is down and east is to the right.
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