Relive the Discoveries of Galileo September 2014 | Page 13

The Durham Region Astronomical Association

How to relive Galileo’s discovery
In this observing exercise, we will study and plot
the bright Pleiades star cluster.

The Pleiades 

The Pleiades, also known as the Seven Sisters of Greek
mythology - the daughters of the titan Atlas and the sea-nymph
Pleione - is an easy sight from autumn through winter and into
early spring. After sunset, the Pleiades can be found high in
the southern sky in the winter, towards the west in spring, or
rising in the east in the autumn (not visible in summer). To find
the cluster, start at the constellation Orion . Follow the line of
Orion’s three belt stars to the upper right towards the distinctive
V pattern of stars that outline the head of Taurus, the Bull .
Continue in the same direction for half that distance again, and
you will spot the Pleiades , a bright knot of stars that looks
like a mini-dipper.

Close-up of the Pleiades
Image by Michael Cook, DRAA

Taurus 

Orion 

Observe with tripodmounted binoculars or a
telescope at low power using an eyepiece of 26 or
higher mm.
Start by
plotting the brightest dozen
stars. Then include the
faint stars, many in long chains that start in the middle of the “bowl” and
wind their way out the sides. Indicate star brightness with the size of the
dots you draw.

The Pleiades, by ____________________________ Date: _____________
your name

mm/dd/yyyy

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