Astronomy

10 ASTRONOMY • DECEMBER 2015

T

he holiday season

is here, and for us

astro geeks that

means toys.

In the quarter

century I’ve written these

columns in Astronomy and

previously Discover, I’ve never

mentioned the equipment I use.

Since I love naked-eye astron-

omy so much, maybe I give the

impression I’m not into optics.

So now for the first time let me

mention what I have, what I rec-

ommend, and how this whole

business is a bit complex.

It’s true, naked-eye astron-

omy is awesome. Away from

city lights, what’s more inspir-

ing than the autumn Milky

Way splitting the sky? When

you think about it, the four

greatest spectacles are all won-

derful to the naked eye: total

solar eclipses, major auroral

displays, great comets, and

brilliant meteor fireballs and

bolides. None requires any

equipment.

But I’m a big fan of binocu-

lars. Of the displays just cited,

total eclipses and comets are

usually enhanced through

them. So are the Milky Way and

open clusters like the Pleiades

(M45). During the 12 years I

ran the astronomy program for

the National Park Service at

Yellowstone, the rangers and I

tried countless visitors’ pairs,

and we particularly adored the

Bausch & Lomb Audubons.

But then came image

stabilization. That changed

the ball game. I love my

Canon 10x30 IS binoculars

STRANGEUNIVERSE

Why all astronomy enthusiasts will happily

equipment-shop forever.

BY BOB BERMAN

Toy s a n d

compromises

FROM OUR INBOX

because they’re lightweight

and have amazing optics. My

Canon 15x45 IS model is also

cool, but almost twice as heavy.

I also have 20x80s on a counter-

weighted swing arm binocular

tripod. I use them all. Still, no

stabilized model offers exit

pupils above 4.2 millimeters,

and in optimally dark condi-

tions, if you’re young enough so

your eyes can adequately dilate,

the brightness of a 5mm to 7mm

exit pupil (as in a 7x50) makes it

an attractive choice.

I also have solar binoculars

on a portable Gemini mirror

platform. This optically perfect,

flat, swiveling-mirror arrange-

ment lets the “glasses” point

downward so that Sun viewing

never requires craning necks

upward. Toys.

When it comes to telescopes,

we enter a world of compromise.

There is no perfect telescope

design; each has its limitations.

I own an old Celestron C5.

Despite its setbacks, how else can

I get a large motor-driven aper-

ture in a portable configuration?

I’ve lived in a dark rural

area for 44 years, and in 1982 I

built a 16-by-20-foot observa-

tory with a motorized roll-off

roof. Its pier-mounted 12.5-

inch f/6 Newtonian telescope

has f lawless optics, with a

5-inch Takahashi refractor rid-

ing piggy back. The massive

mount handles the 250 pounds

(110 kilograms) of instruments

and counterweights, though the

motor’s clutch has a little back-

lash. Spectroscopes are part of

every session.

I haven’t done astrophotogra-

phy since the old film days, but

when I needed long-exposure

tracking with no periodic error,

my drive was excellent at deliv-

ering frustration. I’d labor 35

hours before decently capturing

the Orion Nebula (M42). Hats

off to all of you who take the

gorgeous shots featured in this

magazine.

Anyway, astro toys depend

on what you like to observe,

whether it involves photography,

where you live, your budget, and

your degree of patience. When

price was no object, a wealthy

friend bought a huge Keck-type

dome and had a crane install a

professionally mounted 24-inch

PlaneWave, with a couple

Ta k a ha sh i ref r ac tors r id i ng pig-

gyback. The big scope’s optical

assembly cost $50,000 by itself.

If only price were no obstacle

for us all! And yet he overlooks

a small city and has to endure a

4th-magnitude star limit.

If you have property in, say,

Tibet, you could build a great

observatory, but it would be

hard to duck out for a decent

sandwich. If you live in a city

but can travel to a dark site,

you could buy a big Dob or

Schmidt, but you must be will-

ing to drag the heavy thing

around and periodically col-

limate the optics.

For those who want “easy,”

nothing’s more hassle-free than

a refractor, and these days even

4-inch models are affordable.

But what will you do with it?

We fanatics always find stuff. I

once spent four hours staring at

only Saturn when the night air

was –13° F (–25° C), catching

moments of astonishing detail

unmatched by any photo. On

the other hand, astrophotog-

raphers have their own sets of

fussy requirements.

And if you get the 4-inch,

the modest aperture precludes

stunning looks at galaxies and

globular clusters. The bottom

line is that all telescopes involve

trade-offs. So here is Santa’s

counsel: Make your decision,

and then live with it serenely.

Accept that no single instru-

ment can do everything. Then

that great holiday gift — or the

goodie you’ve wanted for years

— will give only pleasure.

BROWSE THE “STRANGE UNIVERSE” ARCHIVE AT http://www.Astronomy.com/Berman.

Contact me about

my strange universe by visiting

http://skymanbob.com.

WHEN IT COMES TO TELESCOPES,

WE ENTER A WORLD OF COMPROMISE.

Do you question?

Editor David Eicher’s opinion piece on p. 9 of the September

issue, “Part-time believers not needed,” will come back to haunt

him, if he lives long enough. He disses those who question what

is now in the realm of science fiction. Let’s remember Star Trek

“replicators,” “cloaking,” “communicators,” and “lasers.” Or

better yet, recall what the chairman of IBM reportedly stated in

1943, “There is a world market for maybe five computers.” Or

the Digital Equipment president who commented, “There is no

reason anyone would want a computer in his home.” Or even

Lord Kelvin: “Heavier than air f lying machines are impossible.”

— Bob Found, Indian Harbour, Nova Scotia

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