Sky & Telescope - November 2020 - 6

FROM OUR READERS

Fond Remembrances of Fantastic Comets
Ken Hewitt-White's article, "Celebrating Hale-Bopp" (S&T: July 2020, p. 30),
reminded me of one of the highlights
of my career as an airline pilot. We
had a smooth ride on a ﬂight to Seattle
with an aviation-safety inspector in the
jumpseat and Comet Hale-Bopp directly
ahead. I knew a lunar eclipse was in
progress behind us and requested a
90° left turn for 15 miles followed by a
180° right turn to get back on course.
The controller cleared our request and
asked why. "Well, we've got quite a
sight for the passengers!" we replied.
We had the ﬂight attendants turn out
the lights and told everyone that a
lunar eclipse was happening to the left
and Hale-Bopp was visible on the right.
We turned around and switched the
view after a couple of minutes. Other
ﬂights behind us started making the
same request. Judging by the reaction at
the gate, we created several dozen new
stargazers that evening.

I enjoyed Ken Hewitt-White's article.
It brought back many great memories.
I observed Comets Bennett (C/1969
Y1), West (C/1975 V1), and Hyakutake
(C/1996 B2), but Comet Hale-Bopp
(C/1995 O1) is the one I remember as
the best comet of my life.
At that time, CCD astrophotography was coming into its own. My good
friend Jim Edlin built me a camera
based on The CCD Camera Cookbook by
Richard Berry and colleagues. We had
some great times with that camera, but
one night stands out.
I don't remember the date, but
we spent all night in my observatory
photographing Comet Hale-Bopp as
it climbed into the northeastern sky.
I used an 80-mm Orion ED refractor
and took short integrations moving
down the tail. Later, I combined the
images together. That image was at the
top of the Camera Cookbook homepage
for awhile.

Gordon Strader
Nampa, Idaho

James Hannon
Terryville, Connecticut

Triﬁd Nebula's True Colors
In "A Tourist's Guide to the Summer
Highlights" (S&T: July 2020, p. 60), Jerry
Oltion comments that, to his eye, the
emission portion of the Triﬁd Nebula
(M20) appears bluish and the reﬂecting
portion appears reddish - opposite what
images show. I've noted the same thing
using a 14.5-inch Newtonian under dark
skies. I thought the emission portion
appeared blue because it was brighter.
I've also called experienced observers
over to see the seemingly reversed colors
and had them disagree.
In contrast, I've also seen M20 under
exceptional skies at Arches National Park
with a 70-mm refractor. Both components appeared nearly equal in brightness, and both looked white.
Andrew Jaffe
Portsmouth, New Hampshire

A History of Stardust
I applaud Brian Ventrudo's article
"Stellar Archaeology" (S&T: June
2020, p. 58). He clearly and concisely
explains how the study of observable ancient Population II stars allows
astronomers to estimate the history
of the earliest stars, Population III,
which are so far unobservable. His
explanation of the origins and history
of metals that make up younger stars,
including our own Sun, is fascinating.

p James Hannon captured this image of
Comet Hale-Bopp using a homemade CCD
camera from his backyard observatory.

telescope until the image in the ﬁnder
coincides with the view in the other eye.
I'm grateful to the vendor who sold me
the telescope for giving me this tip, when
I wanted a red-dot ﬁnder. He lost a sale
but won a loyal customer.

I was puzzled by the diagram "Origins
of the Elements" on page 64 of Brian
Ventrudo's article. In particular, I did
not understand the inclusion of elements with atomic numbers greater
than iron produced by "Dying low-mass
stars." I can't see how these stars could
produce an appreciable amount of heavy
elements. It wouldn't be by fusion, since
the fusion of elements heavy enough
to make these atoms is endothermic.
Nor could it be by a neutron absorption
process of lighter elements since, as far
as I know, neutrons are not produced in
large amounts during the death of lowmass stars. Could you please explain?

Peter Morris
Harare, Zimbabwe

Paul White
Portsmouth, Rhode Island

t Comet Hale-Bopp put on an incredible show
for skywatchers in 1997. This image of Adam
Horne watching Hale-Bopp through binoculars
appeared in the July 1997 issue of S&T.

A Simple Solution
I read Jerry Olton's article "Finder Finders" (S&T: June 2020, p. 72) with interest
and thought that I should share how I
aim my 8-inch Newtonian. I look at a
bright star with one eye looking directly
at the sky and the other peering through
the ﬁnderscope. Then I move the
6

NOVEMBER 2 02 0 * SK Y & TELESCOPE

JOHNNY HORNE

Jay Bruesch
Excelsior, Minnesota

Sky & Telescope - November 2020

Table of Contents for the Digital Edition of Sky & Telescope - November 2020