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Late Nov 11 p.m.
Early Dec 10 p.m.
Late Dec 9 p.m.
Early Jan 8 p.m.
Late Jan Dusk
These are standard times.
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Moon
Dec 30
Moon
Jan 2
Venus
Binocular Highlight by Mathew Wedel
O
ur destination this month lies in the northeast-
ern reaches of Orion, the Hunter. Set 73 and
74 Orionis near the south edge of your fi eld of view,
and 69 and 72 Orionis near the north edge. You’ll
fi nd yourself looking at a sprawling, complicated
fi eld with chains of bright stars, doubles, at least
one cluster, and more besides.
Right away you’ll notice an arc of bright stars
running east-west like a lopsided smile, bounded
by HD 44033 in the east and Nu (ν) Orionis in the
west. Just south of Xi (ξ) Orionis, four 6th- and
7th-magnitude stars make a miniature arc within
the larger one. Just a bit to the west lies the open
cluster NGC 2169. It’s a small cluster, only about
5 ′ across as seen from Earth, but bright enough
to show up even under moderate light pollution.
At telescopic magnifi cations its stars spell out the
number 37, hence its nickname, the “37 Cluster.”
South of the arc, have a closer look at 73 and
74 Orionis. They look comparably bright, both about
5th magnitude, but that’s an illusion. 74 Orionis is
around three times as bright as the Sun and lies 65
light-years away. 73 Orionis is about 1,200 light-years
away, but it’s also more than 200 times brighter than
its neighbor. I’m a sucker for cosmic odd couples like
this, which remind us of the depths of the night sky.
I haven’t been shy about proposing new aster-
isms in this column, but I just can’t make this fi eld
cohere into a neat picture. If we include 69 and
72 Orionis along with the bright arc, maybe there’s
a cross-eyed Cheshire Cat, or an upside-down
toadstool? I’m really reaching here. A better solution
is to stop trying to impose an order on Nature, and
just take it all as it is.
¢“Just take it all as it is” is on MATT WEDEL’S
bucket list (not checked off yet).
A Stellar Smorgasbord
skyandtelescope.com • JANUARY 2020 43