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Come the Night
Explore the sky northeast of the Veil Nebula.
W
hen night sweeps her velvet robes
across the sky and casts her glitter-
ing gaze our way, she offers us an unend-
ing vista of deep-sky wonders to enjoy.
Sights new to my eye patiently await
discovery in every realm of the heavens.
Thanks to a much-appreciated note fromaccomplished observer and author Steve
Gottlieb, I have a novel addition to my
roll of favorites: Lassell 1.
The constellation Lyra is famed for
the Double-Double (Epsilon Lyrae), two
widely separated stars that are each
close pairs. But Cygnus has a Triple-
Double! It was discovered in 1856 by
the British astronomer William Lassell
and reported in the Monthly Notices of
the Royal Astronomical Society the fol-
lowing year. Lassell called it “a singular
group of three stars, each attended by a
small companion.” The pairs mark the
corners of a northeast-pointing isosceles
triangle with a 1.6′ base and 1.2′ sides.
To locate Lassell 1, hop 2.1° east-
northeast from Zeta (ζ) Cygni to a
golden 6th-magnitude star, the bright-
est in the area. Through a fi nder, this
star marks the shared point of two
diverging 3-star arcs sweeping north-
east for 2.3°, each component shining54 NOVEMBER 2019 • SKY & TELESCOPE
Come, gentle Sister of the starry eyes,
With sable fi ngers open to our sight
Those fi elds of unimaginable skies —
Your vast demesne — Come, gentle
Sister, Night
— Albert Durrant Watson,
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PHDVXUHPHQWVZKHQDSSURSULDWHat magnitude 6 or 7. The stars at the
arcs’ ends make a shallow curve with a
somewhat fainter 7th-magnitude star to
their east. Lassell 1 is 18′ north of that
star and looks like a hazy star clump at
low power. Don’t be fooled by a similar
clump 8½′ northeast.
The members of this unique stel-
lar arrangement are listed as having
magnitudes from 10.6 to 13.5, so I
was pleasantly surprised to spot them
all at 117× in my 130-mm (5.1-inch)
scope. When showing off Lassell 1 at
the Peach State Star Gaze in Georgia,
I boosted the magnifi cation to 164× to
evict a distractingly bright star from the
fi eld of view. Clockwise starting with
the northeastern pair, the component
separations are 19′′, 22′′, and 12′′.
The online Washington Double Star
Catalog lists a 7th star in the system.
Faint and rather close to Lassell 1’s
brightest component, this star wasn’tNOVEMBER 2019 OBSERVING
Deep-Sky Wonders by Sue French
pMost of the light in Abell 78’s outer shell
comes from red hydrogen-alpha emissions,
while the inner ring puts out mostly blue-green
light from doubly ionized oxygen (O III).N