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AJANUARY 2020 OBSERVING
Deep-Sky Wonders by Sue French
Auriga, the
Charioteer
Some of the sky’s fi nest
nebulae and star clustersadorn this constellation.
A
ccording to one myth, Erechtheus
(or Erichthonius) was the mor-
tal son of the Greek god Hephaestus.
Erechtheus created the fi rst four-horse
chariot (quadriga) to ride beneath the
heavens, which impressed the gods and
earned him a place among the stars as
the constellation Auriga.
We’ll start our tour of Auriga’s starry
realm with Melotte 31. This elongated
group of 35 stars spans 2¼° with golden
16 Aurigae at its center. In a suburban
sky, Melotte 31 looks like a hazy glow
to the unaided eye, but a rural sky may
allow you resolve a few of its stars.
The group is easily visible through
a fi nderscope, binoculars, or a small
telescope at low power. The bright starspDeep photographs show that NGC 1931, IC 417, IC 410, and IC 405 (top left, upper left, lower
left, and lower right, respectively) are actually the brightest parts of a single nebula. The bright
stars of asterism Melotte 31 shine between IC 410 and IC 405.strung from 16 to 19 Aurigae are par-
ticularly eye-catching. Sky & Telescope
Senior Editor Alan MacRobert has
long referred to this cute asterism as
the Leaping Minnow, while California
amateur Robert Douglas calls it Auriga’s
Frying Pan. Despite the striking counte-
nance of Melotte 31, its stars seem to be
largely unrelated.
Melotte 31 is named for the British
astronomer Philibert Jacques Melotte,
who included it as one of the 245
objects listed in his 1915 Catalogue of
Star Clusters shown on the Franklin-
Adams Chart Plates. Melotte is also well-
known for his discovery of Pasiphaë,
one of Jupiter’s moons.
Through my 105-mm (4.1-inch)
refractor at 28×, the Minnow shares
the fi eld of view with the emission
nebula IC 410 and its embedded open
cluster NGC 1893. This coarse gather-54 JANUARY 2020 • SKY & TELESCOPE
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ing of suns is framed by a triangle of
9th-magnitude stars and ensnared in
the eastern reaches of a gauzy mist.
The cluster appears about 12′ across,
while the nebula overspreads at least
19 ′. Boosting the power to 76×, I count
forty 9th- to 13th-magnitude stars.
The nebula is patchy and irregular,
with a dimmer bay in its eastern side
and dark blotch just west of the clus-
ter’s center.
NGC 1893 reveals 60 stars, and
it doubles in size when seen through
my 10-inch refl ector at 70×. Many of
the bright stars follow a pattern that
reminds me of a pair of crossed candy
canes, and the brightest star in the
northeastern part shines with a golden
hue. IC 410 stretches westward to a
9th-magnitude star near the cluster’s
edge and faintly beyond toward the
nice double star Espin 332. The pairThou hast loosened the necks of thine
horses, and goaded their fl anks
with affright,
To the race of a course that we know not
on ways that are hid from our sight.
As a wind through the darkness the wheels
of their chariot are whirled,
And the light of its passage is night on the
face of the world.
— Algernon Charles Swinburne,
Erechtheus, 1876