Jungfraujoch High Altitude Research Station and Sphinx Observatory

A shared high laboratory

The Jungfrau railway reached the Jungfraujoch saddle in 1912, and scientists soon saw its value as a laboratory above most of the atmosphere. The International Foundation High Altitude Research Stations Jungfraujoch and Gornergrat (HFSJG) was established in 1930, and the research station opened in 1931. Scientific institutions from several countries, including Belgium, Britain, Germany and Switzerland, use it and share the costs, a model of the international research station.

The Sphinx laboratory, built on a rock crest above the saddle, opened in 1937, and in 1950 an astronomical cupola was installed on its roof.

Cosmic rays, solar spectra and trace gases

High altitude brings the detectors closer to the cosmic rays that arrive from space. In 1949 photographic emulsion plates exposed on the Jungfraujoch gave the first precise evidence of the charged K-meson. Cecil Powell's Bristol group developed the emulsion technique; he received the 1950 Nobel Prize in Physics, and Patrick Blackett, a cosmic-ray pioneer, received it in 1948 for related work.

Above much of the water vapour and dust, the site gave clean infrared solar spectra. Marcel Migeotte of the University of Liège used them in the late 1940s to find methane and carbon monoxide in the Earth's atmosphere, and the Liège group's solar atlas is still a reference. Today the station contributes to the Global Atmosphere Watch with measurements of greenhouse gases, aerosols and ozone-depleting substances.

Recognition

In 2019 the Swiss Academy of Sciences gave the station a Chemical Landmark plaque, recognising its role in atmospheric chemistry. The research station is open throughout the year; scientists reach it by the railway.

The tourist railway as an enabler

The Jungfraujoch station exists because a railway reached the saddle. The same line that brings visitors carries researchers, equipment and supplies. This shared infrastructure is an unusual case of a research station and a tourist attraction sharing one building, with the benefits of access and the costs of crowds and vibration. Researchers manage the interference by restricting where the instruments sit and when they run, and by documenting local sources of pollution. It is a model of how a site can serve several communities if the rules for sharing it are written down.

Instruments and technologies

• Photographic emulsions Plates thick with silver bromide record the tracks of charged particles as lines of developed grains, read under a microscope.
• Solar infrared spectrometer A grating spectrometer fed by a sun-tracking mirror measured absorption lines of gases in the atmosphere above the station.
• Air-sampling and aerosol instruments Inlets and analysers measure the composition of clean free-tropospheric air for climate monitoring.

The people

• Patrick Blackett British physicist and cosmic-ray pioneer, Nobel Prize in Physics 1948.
• Cecil Powell British physicist who developed photographic emulsion detectors, Nobel Prize 1950.

Timeline

• 1930 The HFSJG foundation is established.
• 1931 The international research station opens.
• 1937 The Sphinx laboratory is built.
• 1949 Emulsion plates exposed here give the first precise evidence of the charged K-meson.
• 1950 First astronomical cupola installed on the Sphinx roof.
• 2019 Receives a Chemical Landmark plaque from the Swiss Academy of Sciences.

Key lessons for observation today

• An international station spreads cost and risk A foundation shares the costs among countries and gives each team a fair share of time. Shared infrastructure needs an agreed access policy.
• A good site serves unexpected science A station chosen for cosmic rays also gave the first atmospheric methane and a standard solar atlas. Long-lived sites should be open to new users.
• Clean-air reference sites anchor networks Free-tropospheric sites provide a baseline against which regional pollution can be judged.

Sources

• Wikipedia, Sphinx Observatory
• HFSJG, Jungfraujoch overview
• Swiss Academy of Sciences (SCNAT), Chemical Landmark 2019
• University of Liège, International Scientific Station Jungfraujoch