Sky & Telescope - April 2025 - 6

MACS0416: NASA / ESA / CSA / STSCI / JOSÉ M. DIEGO (IFCA), JORDAN C. J. D'SILVA (UWA), ANTON
M. KOEKEMOER (STSCI), JAKE SUMMERS (ASU), ROGIER WINDHORST (ASU), HAOJING YAN (UNIV. OF
MISSOURI); COMET SKETCH: GREG SIMPSON
FROM OUR READERS
possibility: https://is.gd/WaltherSunset.
If you watch the animation, it illustrates
quite a chomp-down!
I've recently been fixated on Walther
after having caught it back in June.
Then, the rim of the crater was illuminated
all around while the interior was
inky black, save for that region of uplift,
which gave the appearance of a spooky
face rising up out of that deep, dark tarn.
Edgar Allan Poe would have loved it!
Dave Ross
North Canton, Ohio
Breathless Galaxy Cluster
In " Ancient Lights Magnified by Cosmic Lenses " by José Diego and Steven Willner
(S&T: Oct. 2024, p. 36), the opening image is just utterly outstanding and incredible!
This image of an early galaxy cluster that used data from both the James
Webb and Hubble Space Telescopes leaves me breathless. My husband and I just
said " WOW!!! "
Barbara Barnes * Junction, Texas
pThis image of MACS0416 opened " Ancient Lights Magnified by Cosmic Lenses " in the October
issue. The colors indicate wavelength, with the shortest in blue and the longest in red. Redder
galaxies tend to be more distant or are suffused with dust.
Calming Comet
On October 17, 2024, I showed some
of my neighbors the beautiful Comet
Tsuchinshan-ATLAS (C/2023 A3)
through my 8-inch Celestron SchmidtCassegrain,
after reading about it in Bob
King's " Comet Tsuchinshan-ATLAS on
the Morning Stage " (S&T: Sept. 2024,
p. 48) and " Comet Tsuchinshan-ATLAS
Soars at Dusk " (S&T: Oct. 2024, p. 48).
Here in Florida, we had all been
dealing with the stress and
hardship of recovering from
the effects of Hurricane
Milton sweeping across
our state a few weeks
earlier, and I wanted
to share the view with
my neighbors. It was a
fantastic sight, ethereal
and lovely. One of my
neighbors said it reminded
6
APRIL 2025 * SKY & TELESCOPE
him of how beautiful nature can be,
especially after seeing how destructive
and frightening it can be.
I was so moved by those comments
that I not only drew a colored pencil
sketch of how the comet looked
through the eyepiece that evening but
also emailed Bob King to thank him
for his articles. He responded with a
very cordial and friendly email.
Thank you, Bob, for your kindness,
and thank you, S&T, for being
there each month.
Greg Simpson
Pinellas Park, Florida
The Big Chomp
I read Günther Juncker's
letter " The Pac-Man in
the Moon " (S&T: Nov.
2024, p. 6) and would like
to offer Walther Crater as a
Jerry Oltion replies: Excellent find!
Walther Crater certainly looks like a
good candidate for Günther Juncker's PacMan.
It's 134 kilometers across (83 miles), so
it's certainly large enough to be conspicuous
even in a small telescope, and those closing
shadows in the animation certainly do look
like a Pac-Man in action. It looks like this
would be visible right around third quarter.
Cindy Krach, illustrator of my article " Go
Loony for Luna! " (S&T: July 2024, p. 34),
also found that same website, and is including
the Pac-Man in her personal list of Clair
Obscur and Interesting Light Features. She's
also considering making an Astronomical
League observing program with these lunar
features, which would include this interesting
light-ray event as well as others. We tried
to catch this during the last lunation's third
quarter, but the weather stymied us. We'll
keep trying. Thanks for the tip!
"
DIY Refractors
I read Jerry Oltion's " Build Your Own
Refractor " (S&T: Nov. 2024, p. 60) with
interest. As a lidar engineer, I have been
building inexpensive refractors for professional
and personal use for years from
readily available refractive achromats in
the 25-to-100-mm class. I've wondered
why more folks didn't do so given the
availability of quality optics.
The sturdy lens tubes, eyepiece adapters,
and brackets from suppliers like
Thorlabs make the assembly of highquality
refractors up to 3 inches (76
mm) quite easy and relatively cost effective.
Extension adapters can be used to
accommodate lens diameters larger than
3 inches along the lines of Jerry Oltion's
scope, and adapters for 1.25-inch eye

https://www.is.gd/WaltherSunset

Sky & Telescope - April 2025

Table of Contents for the Digital Edition of Sky & Telescope - April 2025