Sky & Telescope - April 2021 - 7

Space Telescope, we can often see the
foreground galaxy (or galaxy cluster) in the
center of the arc or ring.

Bolstering Diversity in
Astronomy
Dara Norman's " Time to Get Serious " (S&T: Dec. 2020, p. 84) mentions
expanding access to make astronomy
more diverse. One of the big issues
when it comes to access is the cost of
museums. For instance, I live in Baltimore, which has a wonderful science
center. However, tickets are expensive.
Many families can't afford to go.
In many cities, there are areas that
have been abandoned and have houses
for sale at extremely low prices. I think
it would be a good idea to raise money,
buy some of these houses, and turn
them into inexpensive museums. For
instance, different rooms can be exhibit
halls. In Baltimore, we have row houses
with ﬂat roofs, so planetariums or telescopes could be placed on top. And the

museums can be staffed by students.
This would increase access by reducing
the cost of attending science museums.
Jason Goldstein
Baltimore, Maryland

S&T Dazzles
The typography on the cover of your
November 2020 issue is such that seen
from even a short distance, the words
that stand out are " SKY & TELESCOPE
. . . Dazzles, " which is 100% true. I am
so pleased with the huge improvements
S&T has been able to make under its
new ownership. I wish Sky & Telescope
truly dazzling success.
W. Scott Peterson
Middlebury, Connecticut

1971

1996

Ernesto de Armas
Piperton, Tennessee

FOR THE RECORD

* The review of Luna Cognita (S&T: Dec.
2020, p. 57) should have stated that the
book's Figure 6.3, and not Figure 6.1,
should show celestial east on the left.
* The label to the right of the " Odd num-

Subaru
Thank you for your fun monthly astronomy podcast. In your December 2020

ber of reflections " image of Mars in " Tips
for Planetary Observers " (S&T: Nov. 2020,
p. 53) should say East.

SUBMISSIONS: Write to Sky & Telescope, One Alewife Center, Suite 300B, Cambridge, MA 02140, USA or email:
letters@skyandtelescope.org. Please limit your comments to 250 words; letters may be edited for brevity and clarity.

75, 50 & 25 YEARS AGO by Roger W. Sinnott
1946

podcast (https://is.gd/Dec2020podcast),
Kelly Beatty mentioned the Pleiades or,
in Japanese, Subaru, like the car. I'm not
sure how many people are aware of this,
but ﬁve Japanese companies merged to
form this automobile enterprise. The
Pleiades were chosen as Subaru's logo
to represent the companies that merged
together to create Fuji Heavy Industries
(the largest star in the logo).

April 1946
Project Diana " Following the
announcement on January 25,
1946, that the Signal Corps experiments were successful in making
contact with the moon by radar,
the imaginations of news reporters
and feature story writers went wild
with predictions that space ships
would soon be a reality. True, our
experiment has shown that it is possible . . . to make continuous radio
contact with rocket ships far out in
space. More important, however,
the experiment has provided a
new means to make studies of the
propagation of radio waves . . .
" Future improvements may lead
to radar methods for measuring
the moon's distance . . . possibly
to the nearest 0.1 mile. Greater
antenna gains at higher frequencies may give antenna beams narrow enough to use to study detail
in the moon's surface. "
Army physicist Harold D. Webb
didn't speculate that surface

details on Mars and Venus might
one day be distinguished by
radar. They were, using the late,
lamented Arecibo radio dish.

Margo F. Aller (University of
Michigan) was describing a lone star
in Andromeda, one of several now
known to harbor promethium.

April 1971
Promethium " Spectroscopic studies of stars often reveal unusual
and puzzling properties of their
atmospheres. One surprising outcome of such a study is the recent
discovery by Charles Cowley and
myself of the existence of the
short-lived unstable element promethium in the atmosphere of the
peculiar A-type star HR 465. . . .
" It is the first demonstration that
this short-lived element can be
present naturally in the universe,
since all isotopes of it known heretofore were produced synthetically.
From the astronomer's viewpoint,
it is direct evidence that element
synthesis can occur near the
surface of a star. Promethium, if
generated in a star's deep interior,
would have decayed to isotopes of
other elements long before rising
to the outer layers . . . "

April 1996
Brown Dwarfs " The year 1995
will likely be remembered by
astronomers for the culmination of
a 20-year hunt: the search for the
substellar objects known as brown
dwarfs. . . . In the Pleiades, observers have uncovered two intriguing
brown-dwarf candidates, while
a third has been found orbiting a
small red star only 19 light-years
away. This third target, known as
Gliese 229B, is so convincing that
many astronomers are finally willing
to remove the word 'candidate' . . .
" [A] brown dwarf is an object
about the size of Jupiter (but with
10 to 80 times its mass) and is
incapable of . . . converting normal
hydrogen into helium in sufficient
quantities to shine steadily. "
Todd J. Henry, now at Georgia State University, offered this
laudatory assessment.
sk yandtelescope.org * APRIL 2 021

https://www.is.gd/Dec2020podcast http://www.skyandtelescope.org

Sky & Telescope - April 2021

Table of Contents for the Digital Edition of Sky & Telescope - April 2021