Sky and Telescope - March 2016 - 32

N

30″

1′

N

COMPARE AND CONTRAST Bertrand Laville sketched M99 as seen with two scopes: a 25-inch Dobsonian at 130-140× (left) and a 10-inch Dobsonian at 127× (right). Don't be afraid to go after the arms with different tools; you may be surprised when a smaller scope reveals something new.

ral arm), and a small, bright core, but no
nucleus. Using a photograph as a guide,
I perceived several condensations on
that northern arm, adjacent to the close
pair of stars beside the arm. With some
difficulty I could also detect a number of
H II regions within the southern arm,
southeast of the galactic core. The southern spiral arm remained hidden; I could
detect just its brightest condensations in
the eyepiece. The most obvious knot lies

M100

JOSEPH D. SCHULMAN

NGC 4322

NGC 4328
N

NEVER LONELY Discovered by Pierre
Méchain on March 15, 1781, M100 is flanked by
two satellite galaxies. Photographs reveal more
than your eye can see, but deep-sky images can
help guide your visual observations.

32

March 2016 sky & telescope

halfway between the core and a 14thmagnitude star beyond the southeastern
flank of the halo.
At 203× M58 was so amorphous in the
16-inch that I couldn't tell whether it was
large or not! Its small, bright core with
a stellar nucleus was apparent, as was a
knot closely following. At 152× the galaxy's
amorphous halo became a little more
apparent, and I suspected a dark lane following the core, with perhaps a spiral arm
beyond the dark lane. The halo and spiral
arm were shown best at 114×. With this
telescope, it's almost unheard of for 114× to
show galactic detail better than 203× does,
but it sometimes happens!
When I turned my 16-inch on the ring
galaxy NGC 4725 in Coma, upping the
magnification to 203×, a long bar aligned
northeast-southwest came into view. The
bar holds a bright little 10″ diameter core
with a nucleus. I saw arcs of the arms
that form a ring at both ends of the bar.
My study was easier at the southwestern
end, since two 14.5-magnitude field stars
interfere with the northeastern arm. In
any case, the arm segments are subtle -
they're not something I'd notice without
knowing they were there and specifically
looking for them. Indeed, they were invisible at both 114× and 261×.
M106 in Canes Venatici, viewed at 203×
in my 16-inch, showed a mottled halo,
about 10′ long and elongated 3:1. The small,
bright elongated core holds a famously

violent nucleus. Of the galaxy's two arms,
the one that runs to the northwest, curling
a little, is the more prominent. I spotted
two elongated condensations along it. The
opposite arm extends to the southeast; it's
quite subtle. A great galaxy!
One of the more famous - but
sometimes more challenging - spirals
M51, also known as the Whirlpool
is M51
Galaxy in Canes Venatici (S&T: July 2011,
p. 26). A textbook example of a grand
design spiral, M51 is interacting with an
irregular dwarf galaxy, NGC 5195. My
8-inch reflector at 174× sometimes shows
segments of M51's spiral arms, bright
nuclei for both galaxies, a foreground star
projected on M51, and a hint of the arm
leading towards NGC 5195. More rarely,
I have recorded a broken-ring structure.
My 16-inch at 203× shows eight knots
along M51's arms, five of them in the arm
not leading to the companion galaxy.
If you keep looking over the decades,
one exceptional night may provide the
memory of a lifetime. Mine occurred in
April 1994, when my 8-inch's mirrors
and eyepiece were freshly cleaned. This
was during a period when I was making
regular visual supernova searches in the
region with the Prince George Astronomical Observatory's 24-inch Cassegrain - it's always easier to see detail with
smaller aperture if you've seen it previously with a large scope. With excellent
seeing and M51 near the zenith, instead

BERTRAND LAVILLE (2)

Cosmic Coils



Sky and Telescope - March 2016

Table of Contents for the Digital Edition of Sky and Telescope - March 2016

Contents
Sky and Telescope - March 2016 - Cover1
Sky and Telescope - March 2016 - Cover2
Sky and Telescope - March 2016 - 1
Sky and Telescope - March 2016 - Contents
Sky and Telescope - March 2016 - 3
Sky and Telescope - March 2016 - A
Sky and Telescope - March 2016 - B
Sky and Telescope - March 2016 - 4
Sky and Telescope - March 2016 - 5
Sky and Telescope - March 2016 - 6
Sky and Telescope - March 2016 - 7
Sky and Telescope - March 2016 - 8
Sky and Telescope - March 2016 - 9
Sky and Telescope - March 2016 - 10
Sky and Telescope - March 2016 - 11
Sky and Telescope - March 2016 - 12
Sky and Telescope - March 2016 - 13
Sky and Telescope - March 2016 - 14
Sky and Telescope - March 2016 - 15
Sky and Telescope - March 2016 - 16
Sky and Telescope - March 2016 - 17
Sky and Telescope - March 2016 - 18
Sky and Telescope - March 2016 - 19
Sky and Telescope - March 2016 - 20
Sky and Telescope - March 2016 - 21
Sky and Telescope - March 2016 - 22
Sky and Telescope - March 2016 - 23
Sky and Telescope - March 2016 - 24
Sky and Telescope - March 2016 - 25
Sky and Telescope - March 2016 - 26
Sky and Telescope - March 2016 - 27
Sky and Telescope - March 2016 - 28
Sky and Telescope - March 2016 - 29
Sky and Telescope - March 2016 - 30
Sky and Telescope - March 2016 - 31
Sky and Telescope - March 2016 - 32
Sky and Telescope - March 2016 - 33
Sky and Telescope - March 2016 - 34
Sky and Telescope - March 2016 - 35
Sky and Telescope - March 2016 - 36
Sky and Telescope - March 2016 - 37
Sky and Telescope - March 2016 - 38
Sky and Telescope - March 2016 - 39
Sky and Telescope - March 2016 - 40
Sky and Telescope - March 2016 - 41
Sky and Telescope - March 2016 - 42
Sky and Telescope - March 2016 - 43
Sky and Telescope - March 2016 - 44
Sky and Telescope - March 2016 - 45
Sky and Telescope - March 2016 - 46
Sky and Telescope - March 2016 - 47
Sky and Telescope - March 2016 - 48
Sky and Telescope - March 2016 - 49
Sky and Telescope - March 2016 - 50
Sky and Telescope - March 2016 - 51
Sky and Telescope - March 2016 - 52
Sky and Telescope - March 2016 - 53
Sky and Telescope - March 2016 - 54
Sky and Telescope - March 2016 - 55
Sky and Telescope - March 2016 - 56
Sky and Telescope - March 2016 - 57
Sky and Telescope - March 2016 - 58
Sky and Telescope - March 2016 - 59
Sky and Telescope - March 2016 - 60
Sky and Telescope - March 2016 - 61
Sky and Telescope - March 2016 - 62
Sky and Telescope - March 2016 - 63
Sky and Telescope - March 2016 - 64
Sky and Telescope - March 2016 - 65
Sky and Telescope - March 2016 - 66
Sky and Telescope - March 2016 - 67
Sky and Telescope - March 2016 - 68
Sky and Telescope - March 2016 - 69
Sky and Telescope - March 2016 - 70
Sky and Telescope - March 2016 - 71
Sky and Telescope - March 2016 - 72
Sky and Telescope - March 2016 - 73
Sky and Telescope - March 2016 - 74
Sky and Telescope - March 2016 - 75
Sky and Telescope - March 2016 - 76
Sky and Telescope - March 2016 - 77
Sky and Telescope - March 2016 - 78
Sky and Telescope - March 2016 - 79
Sky and Telescope - March 2016 - 80
Sky and Telescope - March 2016 - 81
Sky and Telescope - March 2016 - 82
Sky and Telescope - March 2016 - 83
Sky and Telescope - March 2016 - 84
Sky and Telescope - March 2016 - Cover3
Sky and Telescope - March 2016 - Cover4
https://www.nxtbook.com/nxtbooks/aas/st_202012
https://www.nxtbook.com/nxtbooks/aas/st_202011
https://www.nxtbook.com/nxtbooks/aas/st_202010
https://www.nxtbook.com/nxtbooks/aas/st_202009
https://www.nxtbook.com/nxtbooks/aas/st_202008
https://www.nxtbook.com/nxtbooks/aas/st_202007
https://www.nxtbook.com/nxtbooks/aas/st_202006
https://www.nxtbook.com/nxtbooks/aas/st_202005
https://www.nxtbook.com/nxtbooks/aas/st_202004
https://www.nxtbook.com/nxtbooks/aas/st_202003
https://www.nxtbook.com/nxtbooks/aas/st_202002
https://www.nxtbook.com/nxtbooks/aas/st_202001
https://www.nxtbook.com/nxtbooks/aas/st_201912
https://www.nxtbook.com/nxtbooks/aas/st_201911
https://www.nxtbook.com/nxtbooks/aas/st_201910
https://www.nxtbook.com/nxtbooks/aas/st_201909
https://www.nxtbook.com/nxtbooks/aas/st_201908
https://www.nxtbook.com/nxtbooks/aas/st_201907
https://www.nxtbook.com/nxtbooks/aas/st_201906
https://www.nxtbook.com/nxtbooks/aas/st_201905
https://www.nxtbook.com/nxtbooks/aas/st_201904
https://www.nxtbook.com/nxtbooks/aas/st_201903
https://www.nxtbook.com/nxtbooks/aas/st_201902
https://www.nxtbook.com/nxtbooks/aas/st_201901
https://www.nxtbook.com/nxtbooks/aas/st_201812
https://www.nxtbook.com/nxtbooks/aas/st_201811
https://www.nxtbook.com/nxtbooks/aas/st_201810
https://www.nxtbook.com/nxtbooks/aas/st_201809
https://www.nxtbook.com/nxtbooks/aas/st_201808
https://www.nxtbook.com/nxtbooks/aas/st_201807
https://www.nxtbook.com/nxtbooks/aas/st_201806
https://www.nxtbook.com/nxtbooks/aas/st_201805
https://www.nxtbook.com/nxtbooks/aas/st_201804
https://www.nxtbook.com/nxtbooks/aas/st_201803
https://www.nxtbook.com/nxtbooks/aas/st_201802
https://www.nxtbook.com/nxtbooks/aas/st_201801
https://www.nxtbook.com/nxtbooks/aas/st_201712
https://www.nxtbook.com/nxtbooks/aas/st_201711
https://www.nxtbook.com/nxtbooks/aas/st_201710
https://www.nxtbook.com/nxtbooks/aas/st_201709
https://www.nxtbook.com/nxtbooks/aas/st_201708
https://www.nxtbook.com/nxtbooks/aas/st_201707
https://www.nxtbook.com/nxtbooks/aas/st_201706
https://www.nxtbook.com/nxtbooks/aas/st_201705
https://www.nxtbook.com/nxtbooks/aas/st_201704
https://www.nxtbook.com/nxtbooks/aas/st_201703
https://www.nxtbook.com/nxtbooks/aas/st_201702
https://www.nxtbook.com/nxtbooks/aas/st_201701
https://www.nxtbook.com/nxtbooks/aas/st_201612
https://www.nxtbook.com/nxtbooks/aas/st_201611
https://www.nxtbook.com/nxtbooks/newtrack/st_201612
https://www.nxtbook.com/nxtbooks/aas/st_201610
https://www.nxtbook.com/nxtbooks/aas/st_201609
https://www.nxtbook.com/nxtbooks/aas/st_201608
https://www.nxtbook.com/nxtbooks/aas/st_201607
https://www.nxtbook.com/nxtbooks/aas/st_201606
https://www.nxtbook.com/nxtbooks/aas/st_201605
https://www.nxtbook.com/nxtbooks/aas/st_201604
https://www.nxtbook.com/nxtbooks/aas/st_201603
https://www.nxtbook.com/nxtbooks/aas/st_201602
https://www.nxtbook.com/nxtbooks/aas/st_201601
https://www.nxtbook.com/nxtbooks/aas/st_201512
https://www.nxtbook.com/nxtbooks/aas/st_201511
https://www.nxtbook.com/nxtbooks/aas/st_201510
https://www.nxtbook.com/nxtbooks/aas/st_201509
https://www.nxtbook.com/nxtbooks/aas/st_201508
https://www.nxtbook.com/nxtbooks/aas/st_201507
https://www.nxtbook.com/nxtbooks/aas/st_201506
https://www.nxtbook.com/nxtbooks/aas/st_201505
https://www.nxtbook.com/nxtbooks/aas/st_201504
https://www.nxtbook.com/nxtbooks/aas/st_201503
https://www.nxtbook.com/nxtbooks/aas/st_201502
https://www.nxtbook.com/nxtbooks/aas/st_201501
https://www.nxtbook.com/nxtbooks/aas/st_201412
https://www.nxtbook.com/nxtbooks/aas/st_201411
https://www.nxtbook.com/nxtbooks/aas/st_201410
https://www.nxtbook.com/nxtbooks/aas/st_201409
https://www.nxtbook.com/nxtbooks/aas/st_201408
https://www.nxtbook.com/nxtbooks/aas/st_201407
https://www.nxtbook.com/nxtbooks/aas/st_201406
https://www.nxtbook.com/nxtbooks/aas/st_mars
https://www.nxtbook.com/nxtbooks/aas/st_201405
https://www.nxtbook.com/nxtbooks/aas/st_201404
https://www.nxtbook.com/nxtbooks/aas/st_201403
https://www.nxtbook.com/nxtbooks/aas/st_201402
https://www.nxtbook.com/nxtbooks/aas/st_201401
https://www.nxtbook.com/nxtbooks/aas/st_201312
https://www.nxtbook.com/nxtbooks/aas/st_201311
https://www.nxtbook.com/nxtbooks/aas/st_201310
https://www.nxtbook.com/nxtbooks/aas/st_201309
https://www.nxtbook.com/nxtbooks/aas/st_201308
https://www.nxtbook.com/nxtbooks/aas/st_201307
https://www.nxtbook.com/nxtbooks/aas/st_201306
https://www.nxtbook.com/nxtbooks/aas/st_201305
https://www.nxtbook.com/nxtbooks/aas/st_201304
https://www.nxtbook.com/nxtbooks/aas/st_201303
https://www.nxtbook.com/nxtbooks/aas/st_201302
https://www.nxtbook.com/nxtbooks/aas/st_201301
https://www.nxtbook.com/nxtbooks/aas/st_201212
https://www.nxtbook.com/nxtbooks/aas/st_201211
https://www.nxtbook.com/nxtbooks/aas/st_201210
https://www.nxtbook.com/nxtbooks/aas/st_201209
https://www.nxtbook.com/nxtbooks/aas/st_201208
https://www.nxtbook.com/nxtbooks/aas/st_201207
https://www.nxtbook.com/nxtbooks/aas/st_201206
https://www.nxtbook.com/nxtbooks/aas/st_201205
https://www.nxtbook.com/nxtbooks/aas/st_201204
https://www.nxtbook.com/nxtbooks/aas/st_201203
https://www.nxtbook.com/nxtbooks/aas/st_201202
https://www.nxtbook.com/nxtbooks/aas/st_201201
https://www.nxtbook.com/nxtbooks/aas/st_201112
https://www.nxtbook.com/nxtbooks/aas/st_201111
https://www.nxtbook.com/nxtbooks/aas/st_201110
https://www.nxtbook.com/nxtbooks/aas/st_201109
https://www.nxtbook.com/nxtbooks/aas/st_201108
https://www.nxtbook.com/nxtbooks/aas/st_201107
https://www.nxtbook.com/nxtbooks/aas/st_201106
https://www.nxtbook.com/nxtbooks/aas/st_201105
https://www.nxtbook.com/nxtbooks/aas/st_201104
https://www.nxtbook.com/nxtbooks/aas/st_201103
https://www.nxtbook.com/nxtbooks/aas/st_201102
https://www.nxtbook.com/nxtbooks/aas/st_201101
https://www.nxtbook.com/nxtbooks/aas/st_201012
https://www.nxtbook.com/nxtbooks/aas/st_201011
https://www.nxtbook.com/nxtbooks/aas/st_201010
https://www.nxtbook.com/nxtbooks/aas/st_201009
https://www.nxtbook.com/nxtbooks/aas/st_201008
https://www.nxtbook.com/nxtbooks/aas/st_201007
https://www.nxtbook.com/nxtbooks/aas/st_201006
https://www.nxtbook.com/nxtbooks/aas/st_201005
https://www.nxtbook.com/nxtbooks/aas/st_201004
https://www.nxtbook.com/nxtbooks/aas/st_201003
https://www.nxtbook.com/nxtbooks/aas/st_201002
https://www.nxtbook.com/nxtbooks/aas/st_201001
https://www.nxtbookmedia.com