56 March 2014 sky & telescope
OBSERVING
Deep-Sky Wonders
The Twins of Jove
Westernmost Gemini harbors a great variety of nebulae and clusters.
Ye wild-eyed Muses, sing the Twins of Jove,
Whom the fair-ankled Leda, mixed in love
With mighty Saturn’s Heaven-obscuring Child,
On Taygetus, that lofty mountain wild,
Brought forth in joy: mild Pollux, void of blame,
And steed-subduing Castor, heirs of fame.
— Percy Bysshe Shelley
Homer’s Hymn to Castor and Pollux, 1818
According to some tales, Leda had two mortal children
with her husband King Tyndareus and two immortal chil-
dren with the Greek god Zeus (Jove), who came to her in
the form of a swan. Although the original is lost, copies
of Leonardo da Vinci’s painting Leda and the Swan show
brothers being hatched from one swan’s egg and sisters
from another. The girls are Clytemnestra and the beauti-
ful immortal later known as Helen of Troy, “the face that
launched a thousand ships.” The boys are Castor and
immortal Pollux, who grace the sky as the bright winter
constellation Gemini, the Twins.
The splashiest deep-sky wonder in Gemini is the
breathtaking open cluster Messier 35. Even through
15 ×45 image-stabilized binoculars, M35 is big, bright, and
beautiful, with many fairly bright to very faint stars. A
zigzag line of fi eld stars makes it look like a pointy-capped
mushroom growing up out of Castor’s foot. The little,
fuzzy ball of nearby NGC 2158 marks the southwestern
edge of the cap.
M35
NGC 2158
POSS-II / CALTECH / PALOMAR OBSERVATORY
DSW layout.indd 56 12/17/13 2:51 PM