in northern skies, The Big Dipper
is easy to recognize even
viewed upside down.
Part of the larger constellation of
dipper stars above
(left to right along the dipper)
Dubhe, Merak, Phecda, Megrez, Alioth, Mizar/Alcor, and Alkaid.
stars in any given
are unlikely to be physically
But surprisingly, most of the
big dipper stars do seem to
be headed in the same direction as they
space, a property they share with other stars spread out
over an even larger area across the sky.
measured common motion suggests that they all belong
to a loose, nearby
star cluster, thought to
be on average only
about 75 light-years away and up to 30 light-years across.
The cluster is more properly known as the