Australian Sky & Telescope - April 2016__

(Martin Jones) #1
http://www.skyandtelescope.com.au 55

S


ometimes a familiar celestial object turns
out to be not so familiar after all. Messier
44, the naked-eye patch of nebulosity in the
constellation of Cancer, the Crab, has been under
observation since antiquity. It may be better known
as the Beehive, but it’s had many names. The Greeks
and Romans saw a manger here; the Latin Praesepe
remains a popular label for the cluster. In China,
the starry cluster was long interpreted as a group of
captured spirits or demons, Yugui. Perhaps the most
official is its designation as NGC 2632, or Collinder


  1. It’s relatively nearby, maybe 600 light-years
    distant, and composed of about 1,000 stars, the 50
    or so brightest comprising the familiar cluster we
    observe through small telescopes. Many speculate that
    Charles Messier added it to his catalog, along with
    the Orion Nebula and the Pleiades, just to lengthen
    his first published list to 45 for some aesthetic or even
    prideful reason.


Galaxies in the Beehive


A small swarm buzzes inside the famous star cluster.


Observing guides uniformly instruct the viewer
to enjoy M44 with binoculars or to employ low-power
views through the telescope. It’s little wonder that
deep-sky observers often ignore it, dismissing it as
unworthy of detailed study. Many might be surprised
to learn that within the 1° field that the foreground
cluster fills with bright stars lie several distant
galaxies, all of which are very challenging targets.
My first attempt to explore deep between the
stars of the Beehive was inspired by my friend Kent
Blackwell, who arrived at our observing site one night
in February 1998 ready to tackle the project with his
40-cm Dobsonian. The newly published Millennium
Star Atlas showed four galaxies behind the cluster,
and so we set a goal of observing them. My 20-cm
Schmidt-Cassegrain proved to be mostly insufficient
for the task, but that only intensified the challenge.
I have since endeavoured to peek behind the cluster
with larger apertures and have expanded the target

M44

α

β

χ

δ

γ
η

ι

κ

λ

μ

ν

π ο

θ

τ

ψ

ζ

χ

CANCER

M67

8 h 30 m

+25°

9 h 00 m

+20°

+15°

+10°

Star magnitudes

3
4
5
6
7

2647

2643 2637 2625

2624

IC 2388

MCG
+3-22-21

PGC
24335

PGC 24284
¡

M44

CANCER

8 h 44 m

+20°

8 h 42 m 8 h 40 m 8 h 38 m 8 h 36 m

+19°

Star magnitudes

8

7

9
10
11

Ted Forte
Going Deep
Free download pdf