The following article is published here with permission of the Royal Astronomical Society of Canada.
( December / décembre 2015 JRASC | Promoting Astronomy in Canada )
A Brief History of Lunar Exploration: Part I
by Klaus Brasch
And if she faintly glimmers here,
And paled is her light,
Yet alway in her proper sphere
She’s mistress of the night.
From The Moon Poem by Henry David Thoreau
Introduction
An advantage of reaching one’s 75th birthday is the realization
that you are now part of history. To that end, I count myself
fortunate to have experienced a time when night skies were
still quite dark even in big cities. I was ten years old in 1951,
when my father led me to the roof of my grandparents’ house
in Rome, Italy, and showed me the Moon through an old brass
telescope. Seeing craters, mountains, and dull grey features
termed Maria, all in sharp contrast, jolted me into the realization
that I was seeing another world in space and engendered
an awareness of the beauty of the cosmos that has lasted a
lifetime. Later, I was given a book titled La Luna (Fresa, 1943),
which I still have, filled with drawings, facts, and photographs
about and of the Moon. While mostly beyond my comprehension
at the time, this book showed that studying the natural
world was a legitimate and fun thing to do, and set me on my
course of becoming a scientist.
The history of lunar explorations through the ages has been
documented by a number of authors (see e.g. Kopal and
Carder, 1974; Moore, 1963; Sheehan and Dobbins, 2001),
most of these works are dated, very technical or deeply
scholarly, and not really aimed at today’s amateur observer.
This essay will hopefully meet that need.
From Antiquity to the Telescope
It’s safe to say that besides the Sun, the Moon has been the
most influential celestial object in human affairs. Wikipedia
(2015a) lists no less than 70 lunar deities, spanning various
continents, cultures, and mythologies. Not surprisingly, the
monthly lunar cycle has been linked with human menses and
fecundity in many cultures and consequently associated with
female deities like Selene in Greco-Roman mythology and
the Chinese goddess Chang’e (Figure 1). Others, however,
favoured male lunar deities, including Sin in Mesopotamia
and Tsukuyomi in Shintoism.
The Moon has given rise to many myths and superstitions,
as well as some positive omens, in both ancient and modern
times. Lunar eclipses have been particularly maligned,
conjuring visions of demons and ravenous animals. The Incas,
for example, believed that an eclipse was due to a jaguar
devouring the Moon and then crashing to Earth to feast
on humans (Lee, 2014). In ancient China, the Moon was
perceived as a mirror and that dragons swallowed it during
an eclipse. People would beat on mirrors during such events,
causing the dragon to release the Moon once again. In western
history, the term lunatic, from the Latin Luna or moon, has
been widely associated with aberrant human and animal
behaviour. Madness and werewolves—among other myths—
were linked by ancient Greeks to the phases of the Moon
because, they reasoned, since our orb influences ocean tides,
it was likely to affect the human brain as well. These ideas
persisted well into the 17th and 18th centuries in European
folklore and elsewhere. Indeed, even today, it is still commonly
believed that the Moon influences the weather, the times for
crop planting and harvesting, and recently the so-called super
Moon, an astrological rather than astronomical term, regularly
appears on Internet sites. For more The Moon in our Imagination,
see Hockey (1986).
The Moon also plays a pivotal role in Judaism (Wikipedia,
2015b). Rosh Chodesh or Beginning of the Month; lit. Head
of the Month, is the name for the first day of every month in
the Hebrew calendar, and is marked by the new Moon. Based
on the book of Exodus, this established the beginning of the
Hebrew calendar and in Psalm 81:4 both the new and full
Moon are mentioned as a time of awareness.
While the Quran clearly emphasizes that the Moon is a
sign of God, not a deity itself, it plays a significant role in
Islamic religion, which also uses a lunar calendar. The crescent
Moon, called Hilal, defines the start and end of the Islamic
month, and determining the precise time of Hilal is crucial
to specifying the date of Ramadan, a most important time of
atonement. This was one of the reasons early Muslim scholars
studied astronomy (Wikipedia, 2015c).
Figure 1 — From left: Selene, Chang’e, and Sin (All wikicommons)
December / décembre 2015 JRASC | Promoting Astronomy in Canada 251
Figure 2 — Top: Hans Lippershey (1570–1610); Thomas Harriot (1560–1621)
& his Moon chart. Bottom: Galileo Galilei (1564–1642) (Justus Susterman);
Galileo’s sketch of the Moon with comparable photograph (All images
wikicommons)
The realization that the Moon might be another world or
planet like the Earth can be traced back to earliest literature in
both western and eastern cultures. In the 2nd century AD, for
example, Lucian of Samosata wrote a parody titled True Story
about travel to another world with alien inhabitants. Likewise
a 10th-century Japanese folk tale titled The Tale of the Bamboo
Cutter, also involves travel to the Moon, which is inhabited.
After invention of the telescope in the early 1600s, speculation
as to the nature and composition of the Moon reached
a more Earth-centred perspective with references to Maria
or seas to the large dark lunar features and to mountains like
the lunar Alps and Apennines. Belief in the possibility that
our nearest neighbour might be inhabited also reached a new
high, as exemplified in the 1638 book by English astronomer
John Wilkins titled: The Discovery of a World in the Moone or, a
discourse tending to prove that ’tis probable there may be another
habitable world in that planet.
By the 19th century, when our understanding of the Moon
as a planetary-sized body with its own distinct geology and
orbital characteristics had advanced significantly, “hard”
science fiction stories began to appear, instead of just fantasy
voyages involving magic or gods. Notable among these are
From the Earth to the Moon (1865) and its sequel, Around the
Moon (1870), both by the remarkably futuristic French author
Jules Verne. This was followed in 1901 by the H.G. Wells
classic, First Men in the Moon, in which travel to our satellite,
inhabited by insect-like Selenites, is accomplished via an
anti-gravity machine. With advances in rocket science during
the early 20th century, more hard science fiction followed,
including the remarkably realistic 1950 movie, Destination
Moon, a fitting prelude to the soon-to-follow space race, and
culminating in 1968 with the Arthur C. Clark novel and
Stanley Kubrick classic movie, 2001: A Space Odyssey. This epic
saga coincided with the Apollo missions and provided not
only a credible backdrop to manned exploration of the Solar
System, but also a tantalizing prologue to the real possibility
that intelligent life might exist elsewhere in the Universe.
First Light
While it is clear that Galileo Galilei did not invent the
telescope, a device largely attributed to Dutchman Hans
Lippershey, who tried to patent it, nor was Galileo the first to
use one to examine and sketch the Moon. Englishman Thomas
Harriot most likely did, but the great Italian astronomer
was the first to formally publish his findings (Figure 2). His
Sidereus Nuncius (The Starry Messenger), published in 1610, was
a testament to his scientific prowess, and placed Galileo in a
pre-eminent position in the annals of cosmology (Figure 3). As
astrophysicist Richard Learner puts it: “The Starry Messenger…
is more a symptom of his greatness than one of its causes. His
achievements rest on his immense intellectual confidence, even
arrogance. He was confident enough to accept that in eight
months he had accumulated sufficient evidence to reject the
picture of the universe that had been built up by 2000 years of
endeavor by pre-telescopic astronomers: the Book of Genesis
was wrong, the philosopher Aristotle was wrong, the great
Greek astronomer Ptolemy was wrong, even St Thomas Aquinas
was wrong, but Galileo was not” (Learner, 1981).
Galileo’s epic discoveries and their cosmological and theological
implications at the time, inevitably led him into conflict
with the Catholic Church and other authorities. His defence
of Heliocentrism as advocated by Copernicus, coupled with
his clearly strong intellectual arrogance did not help things
either. This is so diplomatically and lovingly alluded to in a
letter by his daughter, Sister Maria Celeste on 1633 April 20,
while Galileo was facing judgement by the Holy Office of the
Inquisition (Sobel, 1999). The letter states in part “The only
thing for you to do now is to guard your good spirits, taking
care not to jeopardize your health with excessive worry, but to
direct your thoughts and hopes to God, Who, like a tender,
loving father, never abandons those who confide in Him and
appeal to Him for help in time of need.”
Galileo, of course, was not the only prominent astronomer
at the time to run into trouble with religious authorities.
His contemporaries, Johannes Kepler, a Protestant, ran into
religious persecution, and Thomas Harriot was accused of
atheism even before starting his astronomical observations
(Learner, 1981).
December / décembre 2015 JRASC | Promoting Astronomy in Canada 252
Figure 3 — Sidereus Nuncius (The Starry Messenger), published in 1610
Nonetheless, with news about the telescope, word spread
quickly across Europe that the device had considerable
military, commercial, and scientific uses. Although Lippershey
claimed first rights, other lens makers, including Dutchman
Jacob Metius and Italian Giambatista della Porta in Naples
made similar claims. In all probability, once the concept of a
telescope and reasonable quality lenses became available, many
people no doubt put two of them together and realized their
potential. Because of this, and despite objections by clergy,
philosophers, and other adherents of the Ptolemaic model of
the Universe, observational astronomy had opened Pandora’s
Box. The Moon, Jupiter’s satellites, the phases of Venus,
sunspots, and endless vistas of stars in the Milky Way, as
described by Galileo, Harriot, Kepler, and many other contemporaries,
gradually shook the foundations of the prevailing
concepts of cosmology in favour of the Copernican model.
Although Galileo’s telescopes were probably among the best
available at the time and his observing skills equal to the task,
his intellectual fortitude was at the root of his many achievements
(Sheehan and Dobbins, 2001). Despite the fact that
some have criticized his published lunar drawings as poorly
executed, lunar-mapping expert Ewen Whitaker points
out that Galileo’s sketches of the Moon’s surface features at
different phase angles were remarkably accurate, especially
given the optical limits and extremely narrow field of view
of his instruments (Whitaker, 1989). Take Figures 2 and
3 for example. As an experienced lunar observer for many
decades, I have often wondered as to the precise identity of
the prominent round feature depicted by Galileo in the southcentral
portion of the lunar disk bisected by the terminator
at both first and last quarter. The dark northern oval is clearly
Mare Imbrium, but the conspicuous southern feature seems
disproportionally large in size to correspond to any obvious
crater or basin.
A few years ago, I was fortunate enough to observe the Moon
just past first quarter through replicas of Galileo’s famous two
parallel-mounted telescopes at the annual Riverside Telescope
Makers conference in Big Bear, California. Their maker, a very
skilled craftsman, had visited the museum in Florence, Italy,
where the originals are housed and was given all specifications as
to glass type, magnifications, lengths, and focal lengths of the
historic instruments by the museum’s archivist. Upon returning
to the US, he fashioned as exact a replica as possible of both
telescopes and their mount.
It took but one glance at the first-quarter Moon through the
20-power telescope to solve the mystery of the large crater; it
was most likely the great walled plain, Albategnius, as suggested
by Whitaker (1989). How did we know? For one thing, the
field of view of Galileo’s refractor was so narrow as to not fully
encompass the entire lunar disk at once. Consequently, what
is depicted as the lunar limb in some of his sketches is most
likely the edge of the field of view, making Albategnius appear
disproportionally large in his rendition, especially under low
angles of illumination. Second, as pointed out before (Whitaker,
1989), many second-tier publications of his bestselling Sidereus
Nuncius were illustrated with vastly inferior woodcut copies of
his drawings and most likely not faithfully.
We also observed Jupiter that night with the replica telescopes
and were astonished to see that while the Jovian disk was just a
dazzling, multi-colored blob; the Galilean moons were clearly
visible. I think all who looked through those telescopes that
evening came away with a new sense that Galileo’s observations
some four centuries ago were not only remarkable in themselves,
but that his essentially correct interpretations of what he saw are
among the most astute in the history of science.
Early Telescopic Studies
Like many advances in astronomy, the study of the Moon
progressed in parallel with improvement in telescope and
eyepiece designs. The extremely narrow field of view and
optical aberrations of the Galilean design were improved
considerably in 1611 through modifications introduced by
Johannes Kepler. This design used a convex lens as eyepiece
in place of a concave one, allowing for a much wider field of
view and greater eye relief (Figure 4). Although the resulting
image is inverted, this combination provided considerably
higher magnification as well (Wikipedia, 2015d). Severe
chromatic aberration was still a problem though, which could
be minimized by using simple objective lenses of very high
f-ratios (Learner, 1981); an approach carried to extremes
by Johannes Hevelius’s 150-foot-long “aerial” or “tubeless
telescope,” and even longer designs by others (Figure 4).
Despite the many limitations of both Galilean and Keplerian
type telescopes, a number of observers produced remarkably
good early lunar maps. This can be attributed to several
factors. The rapid proliferation of optical devices, coupled with
curiosity about the true nature of our satellite, likely led to a
competition to be the first to make new discoveries and attach
names to lunar features; the equivalent of the first Moon-race
(Sheehan and Dobbins, 2001). For instance, between 1609
and 1679, at least a dozen known Moon maps were produced
of varying degrees of accuracy and with a plethora of different
feature names. For complete coverage of this period of lunar
cartography see: Kopal and Carder (1981); Chapter 1, and
Whitaker (1989).
December / décembre 2015 JRASC | Promoting Astronomy in Canada 253
Figure 4 — Top: Keplerian modification of the Galilean telescope, providing
better eye relief, higher magnification, wider field of view, and an inverted
image. Bottom: Woodcut of Johannes Hevelius’s unwieldy “aerial telescope”
in Danzig ca. 1667.
The developmental history of lunar exploration can be grouped
into several phases (Ré, 2014). The pre-telescopic era most
likely began in 450 BC with the speculations by the remarkable
Greek philosopher Democritus, that the Moon contained
mountains and valleys, and ended in 1603 with English
physician William Gilbert’s discovery of lunar libration and
his quite accurate naked-eye map of the full Moon. The birth
of selenography, however, the detailed study of the surface and
physical features of the Moon, began with the invention of
the telescope. The first mapping efforts by Galileo and Harriot
were quickly followed by more systematic attempts by Michel
van Langren (better known as Langrenus) in 1645, Johannes
Hevelius in 1647, and Giovanni Riccioli in 1651, with a little
help from his Jesuit colleague Francesco Grimaldi (Figure
5). All three of these early maps included nomenclatures of
various lunar features, many honouring prominent Catholic
figures in the Langrenus map and terrestrial land features by
Hevelius. Many of these names were subsequently abandoned
except those assigned by Riccioli, most of which gained
gradual acceptance and survive to this day.
Two other major players to enter the astronomical scene in
the mid to late 1600s were Dutchman Christiaan Huygens
(1629-1690) and Italian Giovanni Cassini (1625-1712)
(Figure 6). Equipped with much improved Keplerian-style
telescopes, these two giants of observational astronomy made
some seminal discoveries, both in their respective native
countries and in France at the invitation of King Louis XIV.
Figure 5 — Top left: Langrenus (1645), right: Hevelius (1647)
Bottom left: Riccioli & Grimaldi, right: Cassini (ca. 1680)
Huygens optimized telescope design in two important ways.
He and his brother Constantijn improved lens grinding and
polishing methods, and by combining two plano-convex lenses,
produced the first compound eyepiece with superior eye-relief
and well suited to the very long focal-length-telescopes of
the times (Learner, 1981; Wikipedia, 2015e). In addition,
the Huygens brothers tried to better control these unwieldy
instruments and accommodate their very long focal-length
objectives by eliminating the tube altogether. In these “aerial”
instruments, the objective lens was mounted inside a short iron
tube, which in turn was mounted on a swivelling ball-joint on
top of an adjustable mast. The eyepiece was placed in another
shorter tube and the two were kept in alignment via a taut
connecting string (digiplanet.com).
With such much-improved optics, Christiaan Huygens went
on to discover the true shape of Saturn’s rings, as well as its
main satellite Titan around 1655. He also made some of
the earliest observations and sketches of the Orion Nebula.
Though not principally a lunar observer, he nonetheless left
his mark there too, by being first to record such features as
the Straight Wall, the Huyginus Cleft, and the later-named
Schroeter’s Valley (Sheehan and Dobbins, 2001).
December / décembre 2015 JRASC | Promoting Astronomy in Canada 254
Figure 6 — From left: C. Huygens, G. Cassini, replica of
Newton’s telescope (all wikicommons and public domain)
Huygens’s contemporary, Giovanni Cassini, began his
prodigious astronomical career in 1650 at the University of
Bologna, where he determined the rotational period of Mars as
24 hrs 40 min, very close to the modern value of 24 hrs 37 min,
and generated accurate tables of Jupiter’s moons. Based on this
work, he was subsequently recruited to Paris Observatory in
1669, where he spent the remainder of his life (Sci.ESA, 1999)
[Ed. Giovanni Domenico Cassini became Jean-Dominique
Cassini after he moved to Paris]. Also using the improved very
long telescopes, he accumulated an impressive list of discoveries.
These included surface markings on Mars, the rotation period
of Jupiter, and the main division in Saturn’s rings that still bears
his name. Between 1671 and 1684, he furthermore discovered
four more Saturnian moons, Iapetus, Rhea, Tethys, and Dione
(Learner, 1981; Wikipedia 2015f).
Cassini was also a very accomplished lunar observer. At Paris
Observatory, he established new standards in lunar cartography,
stemming no doubt from his interest in terrestrial
longitude determinations and map making. He made many
drawings of lunar features in different phases, which he then
combined into a 12-foot diameter chart (Ré) (Figure 5). This
map overshadowed essentially all previous efforts with respect
to details and positional accuracy (Kopal and Carder, 1971).
However, as was the case with most lunar observers then, there
was much personal interpretation and poetic license in the
depiction of individual features, particularly due to the notion
that the large dark regions of the Moon were actual seas. A
good example of that is Cassini’s portrayal of the Heracleides
Promontorium at the southern tip of Sinus Iridium, which to
him looked like a lady’s head and the surface of the Sinus itself
as almost wave-like (Sheehan and Dobbins, 2001, p. 31). The
ultimate result of that is that many of the early lunar maps
lacked accuracy and favoured artistic or aesthetic qualities over
precision (Whitaker, 1989).
Most early lunar charts also lacked positional accuracy due
to the vagaries of our satellite’s orbital characteristics, most
notably longitudinal and latitudinal libration. It was known
from the observations by Gilbert in 1603 that the Moon
appeared to rock slightly both from side to side and up and
down as it circled the Earth, thereby revealing peripheral
detail to terrestrial observers. This was fully illustrated on the
charts by both Hevelius and Riccioli, making it very difficult
to establish accurate selenographical coordinates. That in turn,
proved problematic in early attempts by French scientist Pierre
Gassendi (1592-1655) and others to calculate
terrestrial longitudes by timing passage of
major lunar structures through the Earth’s
shadow during eclipses. Finally in 1693, after
decades of effort by several observers, including
Hevelius, Langrenus, French mathematician
Philippe de la Hire (1640–1718), and even
Isaac Newton (1642–1727), to explain lunar libration, Cassini
revealed the exact laws of the Moon’s rotation (Sheehan and
Dobbins, 2001).
The era of long and aerial telescopes probably reached its
peak with the work of Philippe de La Hire, artist, mathematician,
and astronomer. He became part of a circle of French
scientists and intellectuals that included Cassini, Huygens,
René Descartes, and others (Wikipedia, 2015g). Among
many astronomical achievements, he published an artistically
superior map of the Moon, and calculated accurate tables
of the movements of the Sun, Moon, and planets, as well as
determining coordinates of the French coastline and the Paris
meridian.
Although nearly a half-century would pass before it came
into its own, the reflecting telescope was invented by Isaac
Newton, with a working model unveiled in 1668 (Figure 6).
It had many advantages over the very long and cumbersome
non-achromatic refractors of the era (Learner, 1981). These
included: colour-free optics, much shorter and compact design,
and a generally wider field of view. However, Newton’s design
suffered from spherical aberration and his speculum (tin and
copper alloy) mirrors were subject to rapid tarnishing. Although
John Hadley greatly improved optical performance of Newtonian
reflectors in 1721 through use of parabolic mirrors, the
limitations of speculum remained.
Scientific Lunar Cartography
After a long hiatus, the next significant phase in lunar map
making began in the mid-18th century with Johann Tobias
Mayer (1723–1762) (Figure 7), and with development of the
achromatic refractor and the filar micrometer (Kopal and
Carder, 1974; Learner, 1981). In many ways, Mayer was the
father of scientific lunar cartography, since, like Langren a
century before him, he was determined to establish accurate
lunar longitudes using the times of entry of different features
into the Earth’s shadow during a total eclipse. By using the
crater Manilius as central point of his system of coordinates,
Mayer used a glass micrometer to measure the positions of
several other lunar features (Sheehan and Dobbins, 2001). In
this fashion, he generated two maps in orthographic projection
(Figure 7). This remarkable work, as Apollo-era Moon experts
Kopal and Carder (1974) observed, places him in a unique
position in lunar cartography: “….Tobias Mayer became not
only the first modern selenographer of the world, but also the
founder of the German school of selenography which in the
century to come “took” the Moon away from the French and
Italians, and which included Schröter, Lohrmann, Mädler,
Schmidt, and Fauth.”
December / décembre 2015 JRASC | Promoting Astronomy in Canada 255
In addition to establishing a system of lunar coordinates still in
use today, Mayer also made important contributions to studies
of the Moon’s libration and motion, and correctly concluded
that our satellite had little or no atmosphere based on his
observations of instant extinction of stars when occulted by the
Moon. In short, during his unfortunately short life, Mayer’s
work marked the effective end of the era of early telescopic
studies of the Moon and the beginning of the modern phase
of lunar cartography that extends to the present day, now with
manned exploration and mapping by spacecraft.
Following closely in Mayer’s footsteps, Johann Hieronymus
Schröter (1745–1816) would soon become the true father of
modern selenography (Figure 7). Despite his training as a
theologian and later lawyer, like many amateur astronomers,
Schröter was probably inspired by a seminal event, in this case
William Herschel’s discovery of Uranus in 1781. He managed
to get an appointment as magistrate in the small German town
of Lilienthal where, with ample means and time, he was able
to pursue his true passion (Moore, 1963). There he established
an elaborate private observatory in 1778, equipped with several
of Herschel’s excellent telescopes, and later instruments as
large as 18.5 inches aperture, making Lilienthal Observatory
the largest in the world at that time. Although Schröter’s
plans for a detailed 46.5-inch map of the Moon were never
realized, some 75 of his plates were published in two volumes
in 1791 and 1802. Sadly, however, most of his original papers
and observatory were destroyed during the Napoleonic wars in
1813 and he never recovered. Nevertheless, his contributions
to selenography were substantial, involving detailed scrutiny
of selected features under varying degrees of illumination,
determining the altitude of lunar mountains, and developing
a special projection machine to insure positional accuracy not
before attained (Sheehan and Dobbins, 2001).
Although Schröter held many unorthodox beliefs (see below)
and was not a particularly good draftsman, his contributions
to lunar cartography, and indeed several other aspects
of astronomy, were major (Baum, 2007). He was a completely
honest observer and rarely made mistakes; nor did he draw
anything unless sure he had actually seen it (Moore, 1963). His
micrometer-aided measures of lunar mountain heights were
better than anything up to that point, and he independently
rediscovered many features including the Huyginus Cleft, the
Straight Wall, and Schröter’s Valley. He also coined the term
rilles for crack-like features.
Figure 7 — Top row: J. T. Mayer and his orthographic lunar map, Bottom row:
J.H. Schröter and lunar drawing example (all wikimedia)
Much the same applies to his planetary and solar work.
These included his firm establishment that Venus has a dense
atmosphere, and detection of the phase anomaly on Venus,
known as the Schröter effect, referring to the discrepancy
between the predicted and observed dates of dichotomy, as
well as his efforts to determine the rotation period of both
Mercury and Venus, and his discovery of solar granulation
and details of sunspot umbrae (Darling, 2015b). Schröter’s
pioneering efforts at comparative studies of the Moon
and major planets preceded what would later become the
sub-discipline of planetology as endeavoured a century later
by Percival Lowell.
Volcanism and Selenites
In common with many of his contemporaries, Schröter became
deeply interested, one might say obsessed, with the question
of whether lunar craters were formed through volcanism, and
whether the Moon had an atmosphere and might indeed be
inhabited. The question of the origins of lunar craters no doubt
began as soon as Galileo first observed them and adapted the
term from the Greek name for vessel. Over the centuries at
least three competing theories were advanced for the origin
of craters: volcanic eruptions, meteoric impacts, and a most
unlikely notion suggesting glacial action of sorts. In the 17th
and 18th centuries, astronomers were fiercely divided over the
issue of volcanic versus impact origins, as well as whether there
was water and air on the Moon (Sheehan and Dobbins, 2001,
Darling, 2015a). The latter two, of course, would have
implications with respect to possible lunar life.
December / décembre 2015 JRASC | Promoting Astronomy in Canada 256
None others than such luminaries as Hevelius, William
Herschel, and Isaac Newton before him, were convinced that
not only the Moon but also the Sun and other planets were
inhabited by intelligent beings (Baum, 2007, Darling, 2015a).
Although such notions were by no means universally shared,
Schröter most certainly entertained them. As David Darling
(2015b) put it, “Schröter was an enthusiastic pluralist who
wrote that he was fully convinced that every celestial body
may be so arranged physically by the Almighty as to be filled
with living creature….”
He also claimed to have detected an atmosphere on other
planets he thought were inhabited, and attributed what he
perceived as colour changes on the Moon to cultivated lands.
It is perhaps important at this point to emphasize that most
scientists and scholars of that era had strong religious convictions
and were sure that the Almighty would not have created
anything in the Universe without purpose. As a result, belief
in pluralism or conviction in multiplicity of inhabited worlds
was almost universal among Schröter and his contemporaries
(Darling 2015c; Sheehan and Baum, 1995). Once
again, a parallel can be drawn here and a century later, when
enthusiasm, indeed conviction, for the plurality of inhabited
worlds reached a peak of sorts with Percival Lowell, Camille
Flammarion, Giovanni Schiaparelli, Richard Proctor, and
other Mars enthusiasts of the Victorian era, only to be defused
again by scientific reality in the 20th century (Teitel, 2011).
It is noteworthy that both ideas, namely that most craters are
volcanic in origin and that, despite its all-but-nonexistent
atmosphere, the Moon might still harbour some form of life,
persisted into the 1960s. The volcanic origin of craters, so
eloquently proposed by English amateurs James Nasmyth
(1808-1890) and James Carpenter (1840-1899) in 1874, held
sway for nearly a century (Nasmyth and Carpenter, 1874).
Their “fountain model” of volcanic eruption, adapted to the
largely airless Moon and its lower-than-Earth gravity, had
great appeal (Koeberl, 2001) as it seemingly explained both
lunar crater walls and central peaks (Figure 8). Since the art
of high-resolution astronomical photography was not yet
perfected, Nasmyth and Carpenter made stunning plaster-of-
Paris models of lunar features based on detailed visual observations
(Figure 8). Although by mid-20th century the pendulum
had largely swung in favour of the impact hypothesis, several
noted authors, including V.A. Firsoff (1912–1981) (Firsoff,
1959, p. 61), Sir Patrick Moore (1923–2012) (Moore, 1963, p.
106), and even some professional scientists (Simpson, 1966),
still favoured a largely volcanic origin of lunar craters.
Figure 8 — Top: Nasmyth and Carpenter fountain model of lunar crater
formation (Coventry and Warwickshire Astronomical Society, 1993).
Bottom: Rendition of the crater Copernicus by James Carpenter (1874)
Likewise, and no doubt inspired by Percival Lowell’s notions
about Mars and William H. Pickering’s (1858–1938) rather
outlandish theories about plant and insect life on the Moon
(Darling, 2015C), Firsoff concludes as late as 1959: “To sum
up, there does not seem to be any sufficient reason why plants,
even of a highly organized type, should be unable to exist on
the Moon, though probably only in isolated oases of life, the
highlands being almost entirely barren, as they appear to be
on Mars” (Firsoff, 1959, p.178).
Perhaps the most notorious 19th-century advocate for
intelligent life on the Moon, as well as on other planets
including Venus, was Bavarian Franz von Paula Gruithuisen
(1774–1852) (Baum, 2007). An ardent admirer of Schröter’s,
December / décembre 2015 JRASC | Promoting Astronomy in Canada 257
Gruithuisen acquired several of Fraunhofer’s superbly crafted
achromatic refractors ideally suited for lunar and planetary
observations. Fascinated by Schröter’s observations of several
rilles (grooves or clefts) in certain regions of the Moon, he
proceeded to study then in great detail, believing them to be
cities or great monuments built by intelligent Selenites! As
a result of such claims and notwithstanding the fact that he
was an astute observer of both the Moon and the planets,
Gruithuisen is given little credit for his original work and
findings. Among other things, he was one of the first to
suggest that lunar craters are impact features and to note
the bright regions at the poles of Venus, which he thought
were polar caps as on Mars. As noted historian of astronomy
Richard Baum describes him: “…Gruithuisen was an obsessive
pluralist… [and] carried his interest into practice and went
in search of life on other worlds” (Baum, 2007, p. 170). After
observing the illusive Ashen Light on Venus, his imaginings
went beyond the pale, attributing the phenomenon to a
celebratory festival by the planet’s inhabitants (Sheehan
and Brasch, 2013).
References
Baum, R. (2007) The Haunted Observatory, Prometheus Books, Amherst, NY, USA
Darling, D. (2015a) www.daviddarling.info/encyclopedia/H/HerschelW.html
Darling, D. (2015b) www.daviddarling.info/encyclopedia/S/Schroter.html
Darling, D. (2015c) www.daviddarling.info/encyclopedia/M/Moonlife.html
Digiplanet.com (2015) Aerial telescope www.digplanet.com/wiki/Aerial_telescope
Firsoff, V.A. (1959) The Strange World of the Moon. An Enquiry into Lunar Physics. Hutchison & Co. Ltd, London
Fresa, A. (1943) La Luna, Scuola Tipografica, Milan, Italy
Hockey, T.A. (1986) The Book of the Moon, Prentice Hall Press, New York, USA
Koeberl, C. (2001) Craters on the Moon from Galileo to Wegener: a short
history of the impact hypothesis and implications for the study of terrestrial
impact craters, Earth, Moon and Planets, 85-86, 209-224.
Kopal, Z. and Carder, R.W. (1974) Mapping of the Moon, Past and Present, R. Reidel Publishing Company, Dordrecht, Holland
Learner, R. (1981) Astronomy Through the Telescope, Van Nostrand Reinhold, Co., New York, USA
Lee, J.J. (2014) http://news.nationalgeographic.com/news/2014/04/140413-total-lunar-eclipse-myths-space-culturescience/
Moore, P. (1963) Survey of the Moon, Eyre & Spottiswoode, Ltd., London, UK
Nasmyth, J.H. and Carpenter, J. (1874) The Moon: Considered as a Planet, a World and a Satellite, John Murray, London, UK
Ré, P. First Lunar Maps http://astrosurf.com/re
Sheehan, W. and Baum, R. (1995) Observation and inference: Johann Hieronymus Schroeter, 1745-1816, J. Brit. Astron. Assoc. 105, 4, 171-175
Sheehan, W. and Brasch, K. (2013) The “Loch Ness” of Venus, SkyNews,
19, 36-37
Sheehan, W. P. and Dobbins, T. A. (2001) Epic Moon, Willmann-Bell,
Inc., Richmond, VA
Simpson, J.F. (1966) Additional evidence for the volcanic origin of lunar and Martian craters, Earth and Planetary Science Letters, 1, 132-134.
Sci. ESA (1999)
http://sci.esa.int/cassini-huygens/12465-jean-dominique-cassini-andchristiaan-huygens/
Sobel, D. (1999) Galileo’s Daughter, Walker Publishing, Inc., New York, USA
Tarbuck, E.J. and Lutgens, F.K. (2011) Earth: an introduction to physical geology, Prentice Hall, New Jersey, USA
Teitel, A.S. (2011) http://amyshirateitel.com/2011/02/13/mars-avictorian-sensation
Whitaker, E.A. (1989) Selenography in the seventeenth century, chapter
8 in: The General History of Astronomy, vol. 2, Planetary astronomy
from the Renaissance to the rise of astrophysics, René Taton and
Curtis Wilson (Eds.), Cambridge University Press, UK
Wikipedia (2015a) List of Lunar Deities http://en.wikipedia.org/wiki/List_of_lunar_deities
Wikipedia (2015b) Rosh Chodesh http://en.wikipedia.org/wiki/Rosh_Chodesh
Wikipedia (2015c) Allah as Moon-god http://en.wikipedia.org/wiki/Allah_as_Moon-god
Wikipedia (2015d) Refracting Telescopes http://en.wikipedia.org/wiki/Refracting_telescope#Keplerian_Telescope
Wikipedia (2015e) Eyepiece http://en.wikipedia.org/wiki/Eyepiece
Wikipedia (2015f) Giovanni Domenico Cassini http://en.wikipedia.org/
wiki/Giovanni_Domenico_Cassini
Wikipedia (2015g) Johann Heinrich Mädler
December / décembre 2015 JRASC | Promoting Astronomy in Canada 258