SkyNews – September 2019

SEPTEMBER/OCTOBER 2019 •SKYNEWS 25

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S EVERY SHOPPER KNOWS, labels can be misleading. In astronomy, the
winner of the Monster Misnomer award is planetary nebula. The evocative
term was coined by 18th-century astronomers, who noted that certain small
nebulas seemed vaguely planetlike in their telescopes. In reality, these alluring objects
have nothing to do with planets.
When a star becomes old and unstable, it’s prone to sloughing off its
loosely held outer layers. The resulting shell of ejected gas, gently
expanding into space, is what astronomers call a planetary neb-
ula. Hundreds of planetaries dot the night sky, though very
few show well in binoculars. One exception is M 27 , the

Dumbbell Nebula. Within the vast, bal-

looning bubble of M27 are two opposing

lobes of gas—hence the Dumbbell moni -

ker, a reference to the gymnasium barbells

used for weight lifting.

In binoculars, M27 is no barbell, only a

wee puffball. But I’ve managed to ob-

serve it many times in 7×50 binocu-

lars from my suburban yard. The

7.4-magnitude nebula resides in

the constellation Vulpecula the

fox, whose inconspicuous out-

line is swamped by the band

of the Milky Way. My advice is

to locate M27 via the adjacent

constellation, Sagitta the arrow.

Sagitta’s modest star pattern really

is arrowlike. To get to M27, start at

3.5-magnitude Gamma (γ) Sagittae, the

little arrow’s brightest star. North of

Gamma, you’ll see a half-dozen stars

forming a capital letter M. Stretching 3¾

degrees across, the M fits nicely in my

7 ×50s’ field of view. Our puffy prize lies

near the midpoint of the M—which, of

course, stands for Messier!

In my 7×50s, M27 is, at best, a diffuse

dot. That said, it’s an easy sighting pro-

vided I hold the binos steadily. That can be

tough to do—and hard on the neck—

when M27 reaches its maximum height,

which it does soon after nightfall in early

September. To steady my aim, I observe

from a reclining lawn chair or simply lie

flat on the ground. Better yet, I mount my

binos on a camera tripod, then wait until

after midnight, when the target is a bit

lower in the sky.

Binoculars producing extra magnifi -

cation will increase the Dumbbell’s size

and make it easier to spot. M27 appears

much more prominent in my 10×50s.

My favourite bino view is with tripod-

mounted 15×50s, in which the famous

nebula—noticeably enlarged and disc -

like—really does seem like some far-off,

gas-giant planet.✦

FOLLOW THE ‘M’ TO M 27 Adrift in space some 1,200 light-

years from Earth, the Dumbbell Nebula, M27, lies near the

mid dle of an M-shaped asterism 3¼ degrees north of Gamma

(γ) Sagittae. PHOTO BY GARY SERONIK. INSET CHART BY GLENN LEDREW

THE BINOCULAR SKY by KEN HEWITT-WHITE

M27: THE DISTANT DUMBBELL

This famous nebula is well within reach of common binoculars

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