Sky & Telescope - April 2023 - 6

JOANNA FERRARI
FROM OUR READERS
A Model of
Brotherly Love
Teaching Astronomy 101 at Mt. San
Jacinto College in Southern California
has taught me that students enjoy viewing
astronomical instruments in 3D. I
have commissioned my brother Robert, a
retired aerospace engineer from Hughes
Aircraft Company, to build several scale
models of historic telescopes for my
classroom. The latest is a retractable 1
/50
scale model of the James Webb Space
Telescope (JWST). The model took nine
months to complete, much shorter than
the roughly 25 years it took to complete
the actual telescope.
Robert obtained full-size plans for
the telescope from SketchUp. Using
the same software, he then resized the
plans to a scale of 50:1. Next, Robert
modeled the 14 unfolding deployment
steps in SOLIDWORKS to obtain the
correctly sized plans for each individual
moving part. The model's 14
deployments were achieved using 21
magnets and 30 springs.
Pololu Corporation, a machinery
company headquartered in Las Vegas,
Nevada, laser cut the primary mirror,
spiral label, and silicone elastic bands
based off the SOLIDWORKS plans.
The primary mirror was constructed
pBrothers Mark (left) and Robert Maier pose
with their foldable model of the James Webb
Space Telescope.
from gold reflective styrene. Making
the telescoping booms that extend the
sunshield proved to be the most difficult
part of the project. NASA's JWST
website (jwst.nasa.gov) was a valuable
source of information concerning the
layout of the telescope.
When the first pictures from the
JWST were just being released (S&T:
Nov. 2022, p. 12), Robert and I were
both astonished by their beauty and
detail. I am sure that the students in
my Astronomy 101 classes this semester
will greatly appreciate being able to see
this model firsthand.
Mark Maier
Menifee, California
Angling for an Angelfish
In " Riding the Radcliffe Wave "
(S&T: Jan. 2023, p. 26), Brian Ventrudo
states that the Lambda Orionis Nebula,
Sharpless 2-264, is " too faint to spot
visually. " But this emission nebula
is on Chris Beckett's " Wide-Field
Wonders " observing list in RASC's
Observer's Handbook. Beckett calls it
the Angelfish Nebula and recommends
using a hydrogen-beta filter.
My first observation of Sharpless
Roaming Planets
I thought Rebekah Dawson's " Star Huggers "
(S&T: Oct. 2022, p. 28) did an
excellent job of explaining postulated
planet-migration mechanisms and
how they might be correlated to the
observed distribution. The tidal-migration
mechanism was primarily cited
for its orbit circularizing effect, but
little mention was made of progressive
orbital shrinkage due to tidal effects
when the planet orbits faster than the
rotational rate of the star. This effect
would seem to be important in that
close orbiting planets progressively spiral
inward to their destruction.
Lyman J. Petrosky
Latrobe, Pennsylvania
6
APRIL 2023 * SKY & TELESCOPE
Camille Carlisle replies: Thanks
for your letter. I shared your question
with Rebekah Dawson, who replied,
" Tides raised on the planet by the star can
be important for the hottest of hot Jupiters,
and one hot Jupiter very close to its star
(WASP-12) has been observed with its orbit
shrinking due to this effect. Most observed
hot Jupiters are too far from their star for
this effect to be important, but additional,
very close-in hot Jupiters may have been
destroyed by this mechanism. "
"
A Celestial Treat
As a regular subscriber to Sky & Telescope,
I always look forward to Mathew
Wedel's Binocular Highlight column.
Viewing the brilliant Double Cluster
2-264 was at a remote, high-altitude
site in interior British Columbia in
2004, using my 4.1-inch Astroscan
rich-field telescope and a Lumicon
ultra-high-contrast (UHC) filter. Jim
Failes and I both saw two parts of
Sharpless 2-264: a section southwest
of 40 Orionis and a large section
southeast of 37 Orionis. The latter part
extended halfway to Bellatrix (Gamma
Orionis). This was the last object of the
night, and the Astroscan's optical window
fogged up before we could attempt
other sections of the huge nebula.
Our earlier observation of the Witch
Head Nebula (IC 2118, also in Ventrudo's
article) was what made that
night a lifetime memory. Unfiltered,
since it's a reflection nebula, we could
see most of the nebulosity plotted on
Roger W. Sinnott and Michael Perryman's
Millennium Star Atlas. There was
some curvature and a sharper edge on
the side facing Rigel. Unfiltered 7×50
binoculars didn't reveal either nebula
but showed some of Barnard's Loop.
In 2012, my backyard observatory's
16-inch Newtonian at 76× magnification
with the UHC filter detected the edge
of Sharpless 2-264 " by sweeping several
in Perseus (NGC 869 and NGC 884)
is always fun with my 7×50 binoculars
and my 12.5-inch f/5 reflector.
Adding NGC 957 and Trumpler
2 with red giant HD 16068 to my
evening's list of planned objects, as
mentioned in " Roadside Attractions "
(S&T: Nov. 2022, p. 43), has been
a nice treat.
Thank you, Matt!
Ted Harp
Tuttle, OK
https://jwst.nasa.gov/
Sky & Telescope - April 2023

Table of Contents for the Digital Edition of Sky & Telescope - April 2023
