Astronomy - USA (2020-06)

(Antfer) #1

NGC 3201


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M53
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60 ASTRONOMY • JUNE 2020
are Messier objects, so you
know they’ll look great
through medium- to large-
aperture scopes. Because this
list appears in our June issue,
we start with objects visible in
the early-evening spring sky
and end with M79 in the
early-evening winter sky.
Spring
Let’s begin with the faint-
est object on the list, which,
admittedly, is a nontraditional
opener. But in this case, it’s
well worth a look because, at
a distance of 275,000 light-
years, it’s one of our galaxy’s
most remote
globulars. The
Intergalactic
Wanderer
(NGC 2419) lies
in Lynx, itself a
fairly dim constel-
lation. A good way to
locate the magnitude 10.5
glob is to search the star-poor
region 7° north of Castor
(Alpha [α] Geminorum). If
you use a magnification of
200x or greater in an 8-inch
or larger telescope, you’ll see
a 4'-diameter fuzzball with a
slightly brighter center ringed
by a fainter halo that’s not
uniformly lit.
Initially, astronomers
thought NGC 2419 was located
in intergalactic space. But
further study revealed it
does, in fact, belong to the
Milky Way, although
it takes 3 billion years
to complete a single
orbit.
From the faintest
glob, we head to the
one farthest south,
NGC 3201 in Vela. At mag-
nitude 6.8, it’s quite easy to
spot through a finder scope
about 6° west-northwest of
Mu (μ) Velorum. The first
thing you’ll notice is how big
it is — 0.3° in diameter.
A 4-inch scope reveals
only a crowd of unresolvable
stars at the cluster’s bright
center. A 10-inch or larger
instrument will reveal more
than 100 stars. At powers
above 200x, a moderately
dark but shallow V-shaped
indentation is apparent on the
globular’s southern side.
The first Messier object on
our list, M68 in Hydra, glows
at magnitude 7.6 and mea-
sures 12' across. To find it,
look 3.5° south-southeast of
Kraz (Beta [β] Cor vi).
Through a 4-inch scope at
100x, you’ll notice a large, not-
quite-round central region
that spans half of M68’s diam-
eter. From a dark site, a mag-
nification of 200x or more
will let you resolve a dozen or
so of this glob’s stars.
When you look at the
fourth object on the list, M53
in Coma Berenices, you’re
getting a two-for-one treat.
It glows at magnitude 7.7 and
spans a worthy 12.6'. To spot
it, just point your scope 1°
northeast of Diadem (Alpha
Comae Berenices).
Through a 4-inch scope
under a dark sky, you’ll
resolve more than a dozen
outlier stars. But most of
M53’s stars lie at the cluster’s
center. Because this region of
sky doesn’t contain many
stars visible through small
scopes, you’ll easily define
the glob’s edge.
The second part of this
treat is NGC 5053, which
you’ll spot in the same low-
power field of view as M53. At
magnitude 9.9, it’s noticeably
fainter than its partner,
although with a diameter of
10.5', they have comparable
sizes. That, however, is where
the similarity ends. With just
a few dozen widely spaced
stars visible, NGC 5053 looks
more like an open cluster
than a globular. But take in
the big picture and see if you
can pick out its roughly trian-
gular shape.
Moving on, we come to the
second-brightest glob in the
spring sky, M3 in Canes
Venatici. At magnitude 6.3,
it’s visible to the naked eye for
some observers. And, span-
ning 16.2', it’s more than half
the diameter of the Full
Moon. You’ll find it midway
between Arcturus (Alpha
Boötis) and Cor Caroli (Alpha
Canum Venaticorum).
From a dark site, start with
a magnification of 100x and
you’ll get a nice view, even
through a 4-inch scope. You’ll
first notice M3’s large, dense
core, but small scopes won’t
resolve many stars near it.
Through a 10-inch or larger
instrument, however, the
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