Figure 20.1: Repsold meridian circle (La Plata Astronomical Observatory)

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20. La Plata Astronomical Observatory

Juan Carlos Forte and Sofia A. Cora (La Plata, Argentina)

Abstract

La Plata, the current capital city of the province of Buenos
Aires, was founded on 19th November 1882 by governor
Dardo Rocha, and built on a very innovative design giv-
ing emphasis to the quality of the public space, official and
educational buildings. The Astronomical Observatory was
one of the first inhabitants of the main park of the city; its
construction started in 1883 including two telescopes that
ranked among the largest in the southern hemisphere at
that time and also several instruments devoted to positional
astronomy (e. g. a meridian circle and a zenith telescope). A
dedicated effort has being invested during the last 15 years in
order to recover some of the original instrumentation (kept in
a small museum) as well as the distinctive architectural val-
ues. In 1905, the Observatory, the School of Agriculture and
the Museum of Natural Sciences (one of the most important
museums in South America) became part of the backbone
of La Plata National University, an institution with a strong
and distinctive profile in exact and natural sciences. The
First School for Astronomy and Related Sciences had been
harboured by the Observatory since 1935, and became the
current Faculty of Astronomical and Geophysical Sciences in
1983. This last institution carries PhDs programs and also a
number of teaching activities at different levels. These activ-
ities are the roots of a strong connection of the Observatory
with the city.

20.1 Astronomical Observatory as one
of the Founding Institutions of La
Plata National University

La Plata National University (Universidad Nacional de
La Plata) was created in 1905 by Joaquín V. González,
who was Minister of Justice and National Public Ed-
ucation at that time. The Astronomical Observatory
together with the Natural Sciences Museum and the
Veterinary and Agronomy Faculty became the pillars
of the National University. These relevant institutions
gave the scientific profile, more oriented to natural and
exact sciences. The institution began operations on 18th
April 1897 as the La Plata Provincial University (Uni-
versidad Provincial de La Plata) with Dr. Dardo Rocha
as its Rector. In 1906, and after becoming a national

university, Joaquín V. González, was appointed as the
first Rector.
The university coat of arms was adopted at the first

university assembly on 14th February 1897. It represents
the City of La Plata holding up the “Light of Science”.
The constellation of the Southern Cross is also featured
as well as the coat of arms of the Province of Buenos
Aires which is held in the hands of the woman who
represents the city. The university emblem is the oak
leaf, and its motto “Pro Scientia et Patria” is a Latin
phrase meaning “For Science and the Motherland”.
In chronological order, La Plata University is the third

after Buenos Aires and Córdoba and is considered as
one of the most prestigious of the country. Currently,
it has fourteen colleges: Agrarian Sciences, Engineer-
ing, Liberal Arts, Law and Social Sciences, Veterinary,
Exact Sciences, Medicine, Economic Sciences, Natural
Sciences, Astronomical Sciences, Dentistry, Fine Arts,
Architecture and Journalism.
The story tells that Joaquín V. González was im-

pressed by the great comet that became very bright
in September 1982 leading him to choose the Astro-
nomical Observatory as one of the founding institutions
of La Plata National University. In turn, La Plata,
the capital city of the province of Buenos Aires, was
founded by Governor Dardo Rocha (1838–1921) on 19th
November 1882. The construction of the Observatory
was scheduled in a decree passed by on 7th May 1881.
In this decree, the Engineering Department was ordered
to set up plans and a budget for several public buildings,
including an Astronomical Observatory, relevant for the
cartographic survey of the province.
La Plata city is widely known as the one of the best

planned urban system of the 19th century. Urban plan-
ner Pedro Benoit designed a city layout based on a ra-
tionalist conception of urban centers. The city has been
conceived on three fundamental axes on which most
public buildings are located. One is limited by 51st and
53rd avenues and the other two cross it in 7th and 13th
avenues. The House of Government, the Provincial Leg-
islature, the Municipal Palace and the Cathedral rank
among the main buildings. The House of Government
was projected by the Belgian architect Julio Doral. It
has typical Renaissance style and is located opposite the
Provincial Legislature on the other side of San Martín
Square. The Provincial Legislature emerges on the inter-

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Figure 20.2: Areal view of the Observatory at the beginning of 20th century

section of two of those axes on Plaza San Martín. It was
designed by the German architects Gustav Heine and
George H’agemann, from Hannover, who won the con-
test called by the provincial government in 1881. Carlos
Nordman was the architect who directed the construc-
tion. The Municipal Palace is one of the most beautiful
buildings in the city. It has German Renaissance style
and it was designed by the German Architect Uberto
Stier from Hannover School. The Cathedral of the Im-
maculate Conception, is one of the most characteristics
symbols of La Plata. The style is Neogothic, with French
influence. It was inspired by the cathedrals of Amiens
(France) and Cologne (Germany), though smaller. The
project was elaborated by the Department of Engineers
led by Pedro Benoit.
The city Park is a great “lung” which still keeps a con-

siderable area. The buildings that constitute a relevant
part of this traditional park are the open air Martín
Fierro theatre, the Zoo, The Natural Sciences Museum,
and the Astronomical Observatory. As it already men-
tioned, the Natural Sciences Museum was one of the
pillars of the National University. It is a great Greek-
Romanic building, founded by Francisco P. Moreno in
1884. Moreno was the director for 20 years and placed
it in the top international level, with about two million
of classified pieces, a collection he contributed to gather
in a significant way. It holds one of the most important
paleontological and anthropological collections in South
America.

20.2 The First Instrument

The 1882 transit of Venus in front of the Sun had in-
fluence in the decision of constructing an astronomi-
cal observatory and stimulated considerable efforts by
astronomers from countries all around the world. 1st
November 1881, a local commitee was designed to col-
laborate with the French mission from Paris Astronom-
ical Observatory that would observe the phenomenon
from our latitudes. With the aim of observing this event
of worldwide attraction, the provincial government or-
dered an equatorial refracting telescope with 21.6 cm
of aperture and 3.1 m of focal length made by Gautier
House. This first instrument, acquired as part of the
activities that promoted the creation of the Observatory,
has been kept at the observatory of the amateur Ar-
gentinian Association of Astronomy Friends (Asociación
Argentina de Amigos de la Astronomía) since 1942.

The budget for the construction of the public build-
ings, including the astronomical observatory, was ac-
cepted 18th October 1882. Thirteen months later, 22th
November 1883, Francisco Beuf was designated Director
of the construction of the building, thus becoming the
first Director of the Institution. He was a lieutenant of
the French army and director of the Naval Observatory
of Toulon. Astronomers at La Plata, in fact, celebrate
the creation of the Observatory on 22th November.

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Figure 20.3: Large Gautier meridian circle

20.3 Instruments in the Period
1884–1890

In the period 1884–1890, during the Direction of Fran-
cisco Beuf (1883–1889), several telescopes were ac-
quired: a Gautier zenith telescope, an astrograph, a
Zeiss-Gautier reflector, a large Gautier equatorial refrac-
tor and a Gautier meridian circle. In the following, we
describe the main characteristics of these instruments
and their evolution, making a link to the different di-
rectors of the Observatory that contributed to build up
its history and the development of Astrophysics in La
Plata.

One of the purposes of the Observatory was the deter-
mination, by astronomical and geodetical observations,
of the geographical positions of a sufficient number of
places for the construction of an accurate map of the
Province of Buenos Aires. By resolution of 17th March
1884, Director Beuf purchased two zenith telescopes of
8 cm of aperture and 80 cm of focal length from Paul
Gautier of Paris. These instruments were installed in
1887 and 1888.

In April 1886, the purchase of a photographic refrac-
tor of 15 cm of aperture was intrusted to the care of Ad-
miral Mouchez, Director of Paris Observatory. Admiral
Mouchez suggested to buy a larger instrument, similar
to others designed to carry out an important catalogue

of stars covering practically the whole sky, known as
Cart du Ciel.

The astrographic telescope arrived in August of 1890.
During the administration of Director Francisco Porro
Di Somenzi (1906–1910), a new objective from Carl
Zeiss firm was acquired. It was set on the instrument
in August 1913, thus obtaining the first astronomical
pictures with this telescope. The objective has 34.2 cm
of aperture and 3.42 m of focal length. Since then, pho-
tographic observations of asteroids and comets had been
taking place at La Plata Observatory. This telescope
worked till 1986, providing a large number of photo-
graphic plates. During those years, the observatory
contributed made significant contributions to the accu-
rate determination of positions of asteroids and comets.
Several asteroids were discovered in that period, such as
(965) Angélica, (1029) La Plata and (1254) Erfodia.

In April 1886, a reflector telescope of 80 cm of aper-
ture was ordered from Paris Observatory. The instru-
ment was assembled by Gautier and finished in 1887.
The optical devices were provided by Paul and Pros-
per Henry. The original large mirror was finished in
1889. Several modifications have been introduced since
1921 such as a new mirror provided by the firm Zeiss
of Jena, Germany, in 1930, changing from a Newto-
nian to a Cassegrain system. These improvements were
done by Dr. Johannes Hartmann, a German Director
of the Observatory in the period comprised between

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Figure 20.4: Zeiss-Gautier reflector telescope

200



1921 and 1934, who tried to promote the astrophysic
and astrographic research activities. During this period,
the asteroids Angélica, La Plata and Erfordia, already
mentioned, were discovered and the programmes and
observations of Eros and the Nova Pictoris were started.
However, the instrument was not much used during this
period. In 1954, several improvements were made by the
mechanic Herbert Glinschert under the indications of
Dr. Livio Gratton and during the direction of Guillermo
O. Wallbrecher (1947–1955).
In April 1887, the acquisition of a refractor telescope

of 43.3 cm of diameter and 9.6 m of focal length was
approved. The assembly of this instrument was done by
Gautier and finished in 1894. The optical devices of this
large Gautier equatorial telescope were manufactured by
Paul and Prosper Henry. Scientific research carried out
with this instrument includes the observation of binary
stars and asteroids and Mars opposition of 1956.
That same year, by resolution of 4th May 1887, the

acquisition of a meridian circle refractor telescope was
authorized. This instrument was designed by P. Gautier
with the aim of being one of the largest and best tele-
scopes of this kind in the world. The objective of this
large meridian circle has 21.3 cm of aperture and 2.8 m
of focal length (from the firm Henry Brothers). This
telescope reached Buenos Aires in April 1890.

20.4 Instruments around 1906

In January, 1906, Dr. Francisco Porro di Somenzi was
appointed Director of the Observatory and also became
the first Dean of the Faculty of the Mathematical, Phys-
ical, and Astronomical Sciences that was created within
the Observatory. Among the instruments obtained on
Dr. Porro’s initiative, was a Repsold meridian circle,
a Zeiss comet-seeker, two Repsold transit instruments
and Wanschaff zenith telescopes. We present now a brief
description of the acquisition and main features of these
instruments.
In October 1906, Director Porro placed an order with

the celebrated firm A. Repsold & Son of Hamburg,
for the construction of a large meridian circle. This
instrument has a two-lens objective by Carl Zeiss, hav-
ing 19 cm of aperture and 2.8 m of focal length. It was
received in La Plata in May 1908. In 1932, the Director
Johannes Hartmann lent the instrument to the Córdoba
Astronomical Observatory, after having keeping it in its
packing during a quarter of century. In 1934, during the
Direction of Ing. Félix Aguilar (1934–1943), specialist in
geodesy, the instrument returned to La Plata, replacing
the large Gautier meridian circle in 1938.
While in Europe, and also in 1906, Director Porro or-

dered a comet-seeker to the well-known firm Carl Zeiss.
The telescope has 20 cm of aperture and 1.38 m of focal
length. It was with this instrument that astronomer
Pablo T. Delavan on 26th September 1913, discovered
the comet 1913d, an interesting discovery since it was
the second apparition of Westphal’s comet, 1852.

Two astronomical transit instruments were con-
structed by the house A. Repsold & Son of Hamburg,
one of which was received in 1906 and the other in

1907. The objectives were made by Steinheil of Munich
of 7.5 cm of aperture and 75 cm of focal length.
The zenith telescope was constructed by Julius Wan-

schaff, from Berlin. It is like all the zenith telescopes
furnished by this maker for latitude observatories of the
International Geodetical Association.
In 1945, Félix Aguilar proposed the construction of

an astrometric station to better determine the position
of circumpolar stars. It was established in Santa Cruz,
in the south of the town Paso del Río La Leona, being
the southernmost observatory at that time. The obser-
vations were done with the Repsold meridian circle.

20.5 Other Instruments
Among the instruments acquired in the two above men-
tioned periods, only the Zeiss-Gautier reflector tele-
scope, the large Gautier equatorial refractor telescope
and the Zeiss comet-seeker are currently in use, mainly
for teaching activities aimed to the general public. The
Zeiss-Gautier reflector telescope is also used with aca-
demic purposes, and some astronomical projects are car-
ried out by both astronomers and undergraduate stu-
dents. There is, however, a bigger reflector telescope of
2.15 m that was bought during the sixties thanks to the
efforts of Dr. Jorge Sahade. It was installed in San Juan
in 1986 and is currently used as a national facility.
A Mainka seismograph, a GPS system part a world-

wide net, and a meteorological tower are also within
the current equipment of the Observatory. Since the
beginning of the 20th century, the institution has also
had several clocks systems designed to provide accurate
time to a number of different observing instruments.

20.6 Main Buildings Today
The Observatory extends over 7 ha area with 18 build-
ings, including domes and the small shelter for the Wan-
schaff telescope. The construction of these buildings
started in 1885 and finished a decade later. Between
1885 and 1886, the small equatorial building and the
east and west pavilions were built, and are used today
as the Electronic and Astrometric Department, respec-
tively. In 1889, the main building and the one hosting
the Repsold meridian circle, that is currently used as a
conference room, were finished. In 1891, the construc-
tion of the domes for the Zeiss-Gautier reflector tele-
scope and the astrographic telescope were carried out.
In turn, the building that host the Gautier equatorial
refractor telescope was finished in 1895. The ground
floor of this building became the Museum of Astronomy
and Geophysics. This museum was created in May 1997
by the Astronomical and Geophysical Faculty (Facultad
de Ciencias Astronómicas y Geofísicas), within the Web
of Museums of La Plata National University. The main

201



Figure 20.5: Building that hosts the Gautier equatorial refractor telescope, where the Museum of Astronomy and Geophysics
currently operates

purposes of this museum are the restauration and con-
servation of the historical patrimony of the Observatory,
mainly composed by the instruments acquired at the
beginning of 20th century. For example, a Zeiss “blink
microscope” for asteroids and variable stars research,
as well as parts of the Repsold meridian circle and a
photometric camera, among others.
The architectural style of these buildings are the same

as those characterizing the main public buildings of La
Plata city at the end of 19th century, most of them cre-
ated by the Ingeneering Department, directed by Pedro
Benoit.

20.7 Brief Description of the Main
Building

The main building was originally used in part as the
House of Directors. Contiguous to the current main
entrance corridor, there is another one, that leads to
the library, one of the most beautiful rooms of the ob-
servatory. The floor is made of heart pine and the room
is equipped with a large size table. One of the objectives
of the observatory, at the time of its foundation, was to

make a cartographic survey of the Province of Buenos
Aires and that table was used for spreading and unfold-
ing the large charts the experts had to draw. Since the
table is wider that the door of the library, it is believed
that it was assembled inside this room. There is also
an antique cast brass gas chandelier. There is not much
information about the origins of this lamp that main-
tains its original shape. It has several ornate arms with
etched lampshades. In the 1880s, there was no electrical
wiring in La Plata, so this chandelier ran on gas, which
circulated down from the ceiling through the pipe into
the arms. The ceiling of the library is ornamented with
carvings and a central rosette. In the corners, there
are paintings of different telescopes that still remain
at the Observatory. Important meetings took place at
this library, like the Symposium on Stellar Evolution
in 1960, organized by Dr. Jorge Sahade. Outstanding
astronomers, like Carlos Jaschek, Maarten Schmidt, Al-
lan Sandage, Margaret and Geoffrey Burbidge, Olin J.
Eggen, Alex Feinstein and José Luis Sérsic attended that
remarkable meeting. Currently, the library is frequently
used for special events connected with the institutional
life of the observatory.

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Figure 20.6: Current view of the main building

Connected to the library is the Dean’s office, where
meetings of the Academic Board take place. Just out-
side of this room, in the external part of the building,
there is a gallery with missing statues corresponding to
famous astronomers, like Newton, Kepler and Galileo.
The story tells that the statues were lost with the sinking
of the ship that was bringing them to La Plata. In fact,
and as recently found in old recovered documents, these
statues were never bought because of budget reductions.
Many of the original rooms of the original building are

currently offices occupied by scientists, engineers and
the Observatory administration.

20.8 Concluding Remarks
The most significant restauration works that have been
done include the buildings that host the Gautier refrac-
tor telescope and the Zeiss-Gautier reflector telescope,
and the ceiling of the library. They were carried out by
the architect Leonforte, and specialist of Fine Arts.
On the other hand, future projects involve the con-

struction of a Planetarium within the park of the Ob-
servatory, that will contribute to enhance the profile of
the City Park as a scientific and cultural circuit that
will also include the Zoo and the Museum of Natural
Sciences.
Regarding the academic aspects, Félix Aguilar pro-

moted the creation of the Superior School on Astronom-
ical and Related Sciences (Escuela Superior de Ciencias
Astronómicas y Conexas) between 1934 and 1935. In
1948, the graduate course of Geophysics was created.
Later, in 1983, these Schools merged into the current

Faculty of Astronomical and Geophysical Sciences, be-
ing Ing. Pastor Sierra its first Dean. Both students and
professors keep a deep connection with the historical
past of the Observatory and there is a strong commit-
ment to preserve the value of this unique cultural her-
itage.

Acknowledgements

We are very grateful to Prof. Dr. Gudrun Wolfschmidt
for her kind invitation to present this work about
La Plata Observatory, and for the financial support
provided. We acknowledge Facultad de Ciencias As-
tronómicas y Geofísicas for the financial help offered.
We thank Raúl Perdomo, Guillermo E. Sierra, Pablo
M. Cincotta, Sixto Gimenez Benitez, Roberto Venero,
Erica Scorians and Mabel Peiró for useful information
and pictures. Many pictures and details of the instru-
ments and building were obtained from the web page of
the Museum of Astronomy and Geophysics.

20.9 Bibliography
Perdomo, R. A.: “El Observatorio Astronómico de La

Plata”. Proceedings of the Workshop on Historia de la
Astronomía Argentina. Ed. by G. E. Romero, S. A.
Cora and S. A. Cellone. La Plata 2008, in press.

Publicaciones, Tomo I. Descripción general del Obser-
vatorio, su posición geográfica y observaciones de
cometas y estrellas dobles. La Plata: Observatorio
Astronómico 1914.

203