Key dates of the Neuchâtel Observatory

Observatory in 1862, with the first director Adolphe Hirsch and his dog (L’Observatoire Cantonal neuchâtelois 1858-1912 – State archives)
From left to right: Hirsch Pavilion with Zeiss telescope and seismograph (main building for the exhibition), director’s house, first building of the observatory which housed the Meridian telescope and the laboratories, cleanroom building of the CSEM. (Photo: E. Bettinelli, 2011)

1857 / 1858
The State of Neuchâtel confirms the construction and the plans of an observatory.
The german Adolphe Hirsch is the founder and the first director at the age of 28. He was born in Halberstadt in Germany.

1859 / 1860
Construction of the first buildings.

First Meridian Telescope (L’Observatoire Cantonal neuchâtelois 1858-1912)

Hourly signal sent every day by telegraphic line, to Neuchâtel, La Chaux-de-Fonds, Le Locle and Bern.

The time is precise to two hundredth of a second.

Construction of the Chaumont sight (Mountain above Neuchâtel). Agreement with P & T for the distribution of the time signal.

Sight of Chaumont (Photo: Pierre Sydler)

Introduction of universal time. The Observatory continues to send its local time, specifying that the time difference is 1 h. 32 min. 10 s. 4.

1901 April 16th
Death of Dr Hirsch. He gives his fortune to the State of Neuchâtel to build the Hirsch Pavilion.
Mr. Louis Arndt is the second director.

Chronometric service hall with the director Louis Arndt and his assistant (1901-1912?) (L’Observatoire Cantonal neuchâtelois 1858-1912)

First project for the transmission of the hour by radio waves.

Schema TSF signal

Opening of the Hirsch Pavilion.

First mention of the photographic study of variable stars (Delta Cephei).

Installation of the QuervainPiccard seismograph. Broadcast, by Radio-Bern, of beats of seconds of one of the pendulums of the Observatory.

Seismograph Quervain-Piccard (© Marie Juan archives)
Seismogram of the earthquake of December 21, 1929 (La station séismologique de l’Observatoire
astronomique et chronométrique de Neuchâtel – Bulletin de la Société Neuchâteloise des Sciences Naturelles)

Retirement of Mr. Louis Arndt. Mr. Edmond Guyot is the third director.

The Observatory is on the list of the 10 best observatories in the world.

Edmond Guyot signing a march report form (© Family Guyot archives)

First quartz clock of the Observatory.

Retirement of Mr. Edmond Guyot. He is replaced by Mr. Jean-Pierre Blaser.

Beginning of the Neuchâtel HBN transmitter on 2,5 and 5 MHz, as well as the Münchenbuchsee HBB transmitter on 96 kHz. Beginning of the speaking clock and distribution of time.

Video still: Chronograph control (Bibliothèque de La Chaux-de-Fonds – DAV)

Centenary of the Observatory. Presentation of the Ch.-Ed. Guillaume Nobel Prize Medal to the Observatory by his family. First writings on atomic time.

Retirement of Mr. Jean-Pierre Blaser. He is replaced by Mr. Jacques Bonanomi.

The time of the Observatory becomes the standard time in Switzerland.

12th General Conference of Weights and Measurements. It replaces the astronomical unit of the second by that of the cesium clock.

The first quartz clocks beat all the records in the chronometry contest.

The measurements made at the PZT zenith telescope, still collected by the International Bureau of the Hour, are still considered the best in the world. Final adoption on the paper of the atomic second as a unit of time.

The seismology service is only summarily maintained

Donation of the meridian telescope to the Musée international d’horlogerie (MIH) in La Chaux-de-Fonds.

Meridian telescope in the Musée international d’horlogerie in La Chaux-de-Fonds

It is the end of the definition of the international time by the Observatory. The United States, Canada and Germany are the references.

End of the measures with PZT Telescop.

Aperitif for the retirement of Jacques Bonanomi (© Marie Juan archives)

Retirement of Mr. Jacques Bonanomi. He is replaced by Mr. Giovanni Busca.

Giovanni Busca with the Zeiss Telescope

Retirement of Mr. Giovanni Busca. He is replaced by Mr. Alain Maurissen.

Atomic Clock, Hydrogen Maser for Galileo Satellite (L’Observatoire de Neuchâtel. Son histoire de 1858 à 2007 – Lucien Trueb)

End of the activities of the Observatory. The institution was dissolved and integrated into the University of Neuchâtel (Time and Frenquency Laboratory) and the Swiss Center for Electronics and Microtechnology (CSEM)

Building of the Meridian telescope