Sky & Telescope - August 2019 - 7

Before purchasing a commercial Barlowed laser collimator, I had been using
a cardboard laser collimation target I
would slip over the bottom end of the
focuser tube. As it turned out, I had
forgotten to remove it and was trying
to view the Double Cluster with an eyepiece stopped down to 6-mm aperture!
Steve Emert
White Bear Lake, Minnesota

Found in Space
Great article on Alpha Centauri (S&T:
Apr. 2019, p. 34). This star and the
1960s television show Lost in Space -
the Robinsons were headed there - were
what ﬁrst got me interested in astronomy. I tried to ﬁnd out all I could about
it, which wasn't easy back then. But in
the Army and on guard duty one night
on the Big Island of Hawai'i, I spotted
it. That was the only time I've ever seen
it. I'd love to see it through a telescope,
but at this point in my life, that looks
unlikely. I hope you'll keep us posted on

any planet discoveries in that system.
We may need to send the Robinsons out
there someday if we screw up Earth!
Ed Bailey
Daniels, West Virginia

Another Amateur Discovery
Congratulations to Giuseppe Donatiello
on his discovery of a dwarf galaxy (S&T:
Mar. 2019, p. 9). His keen-eyed observation reminds me of another amateur
who has, more recently, also discovered
a previously unknown galaxy.
In 2017 Rick Steiling, a member
of my local club, the Astronomical
Society of Eastern Missouri, discovered
a faint smudge on one of his images of
the NGC 2655 ﬁeld. With the help of
fellow club member Dan Crowson and
much sleuthing, Rick was ﬁnally able to
verify that he had discovered a hitherto unknown low-surface-brightness

1969

1994

Bill Sheehy
Chesterﬁeld, Missouri

FOR THE RECORD

* While Juno was the first spacecraft to
image Jupiter's poles (S&T: May 2019, p.
16), other spacecraft have come close to
its polar perspective. Ulysses flew on a solar polar orbit, so it too flew over Jupiter's
poles, though at a greater distance and
without a camera. The Pioneer mission also
flew by but at a more oblique angle that
prevented seeing the poles themselves.

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75, 50 & 25 YEARS AGO by Roger W. Sinnott
1944

galaxy. He and Dan published a paper
in Research Notes of the AAS (Apr. 24,
2018), which became one of the most
downloaded papers in American Astronomical Society journals in 2018. For
the article, see https://is.gd/steilingﬁnd.
To read a discussion of the potential
importance of Rick's discovery, see
https://is.gd/mzs5Zk.

º August 1944
Moon Rockets? "There are many
experts who believe . . . that the
day may not be far distant when we
shall be exploring outer space in
person - possibly 500 years from
now, possibly in 1,000 years. Some
think it may come even sooner than
that, after the war perhaps, when
men's minds will turn once more to
the peacetime utility of rockets and
rocket ships. Perhaps, they say,
before some now alive have died,
rocket-liner trips to the moon may
be a common daily performance.
This is wild supposition, not scientific statement. But there are those
who believe it."
Marian Lockwood was an early
columnist for Sky & Telescope and
its predecessor, The Sky.
º August 1969
Gravitational Waves "If the
results of a delicate experiment by
Joseph Weber of the University
of Maryland have been correctly

interpreted, gravitational radiation
reaching Earth from space has
finally been detected. . . . He uses
two or more detectors [600 miles
apart, each being] a one-ton aluminum cylinder about five feet long,
with piezoelectric crystals bonded
to its surface. . . .
"Dr. Weber's report covers an
81-day monitoring period. During
this interval, more than 17 significant coincidences were recorded."
Weber's results were never
conﬁrmed, but many astronomers
credit him with founding the ﬁeld
of gravitational-wave detection. He
died in 2000. The ﬁrst true waves
were picked up in 2015 from the
faraway merger of two black holes,
probably in the south-circumpolar
sky. (See also a related item, next.)
º August 1994
Gamma-Ray Bursts "About once
a day an explosion somewhere in
space produces an intense blast
of gamma rays that is detected
by Earth-orbiting or interplanetary
spacecraft. We don't know what

causes these bursts or where they
are produced. They do not appear
to generate radiation in any other
energy range. . . . Gamma-ray
bursts remain among the most baffling phenomena in astronomy. . . .
"There are good reasons to
reject all of the proposed solutions
to the gamma-ray burst enigma.
Adherents of any one model find
it easier to critique rival theories
than to defend their own. Most
researchers remain agnostics,
awaiting some observation or theoretical development that will crack
the case. . . . It is humbling that we
do not know the distance scale of
the burst sources to better than 10
orders of magnitude."
Charles Meegan was lamenting
more than two decades of failed
efforts to understand gamma-ray
bursts (GRBs). But his Compton
Gamma Ray Observatory team
ﬁnally, in 1997, linked them to
potent explosions in remote galaxies. In 2017 a GRB coincided with
gravitational waves detected when
two neutron stars merged in Hydra.

sk yandtele scope.com * AUGU S T 2 019

https://www.is.gd/steilingfi https://www.is.gd/mzs5Zk http://www.skyandtelescope.com

Sky & Telescope - August 2019

Table of Contents for the Digital Edition of Sky & Telescope - August 2019