History of ASTRON

James Clerk Maxwell (Edinburgh, June 13, 1831 – Cambridge, November 5, 1879) establishes the theory of electro-magnetism.

Heinrich Hertz (Hamburg, February 22, 1857 – Bonn, January 1, 1894) confirms Maxwell’s theory with the generation and reception of the first man-made radio waves.

Guglielmo Marconi (Bologna, April 25, 1874 – Rome, July 20, 1937) makes the first radio transmissions across the Atlantic Ocean – the modern age of wireless radio communications begins.

Karl Jansky (Norman (Oklahoma), October 22, 1905 – Red Bank (New Jersey), February 14, 1950) discovers the first natural cosmic radio emission from the centre of our own Galaxy, the Milky Way.

Grote Reber (Chicago, December 22, 1911 – Tasmania, December 20, 2002) begins construction of the first large parabolic antenna, later publishing the first systematic radio surveys of the sky. For the first time, the non-thermal radio universe is revealed and high-energy astrophysics is born.

News of Reber’s work reaches Prof. Jan Hendrik Oort in Leiden. Realising that radio emission might permit him to map out the structure of the Milky Way, he asks a young PhD student, Henk van de Hulst to investigate further. Van de Hulst predicts that neutral hydrogen (the most abundant element in the Universe) should be detectable as a radio spectral line at a wavelength of 21 cm.

On 23 April 1949, the forerunner of ASTRON, SRZM (Stichting Radiostraling van Zon en Melkweg / Netherlands Foundation for Radio Astronomy) was officially founded with Prof. Jan Oort (Franeker, April 28, 1900 – Leiden, November 5, 1992) as chairman of the Board, a position he held until his retirement in 1970. SRZM was set up to prepare for the design, construction and operation of the Dwingeloo Telescope.

A young engineer, Lex Muller builds a radio receiver sensitive to radio waves at 21 cm. As predicted earlier by Van de Hulst, Neutral Hydrogen is detected by Muller & Oort using the Würzburg telescope at Kootwijk. With these data, Oort and others map out the spiral structure of the Milky Way.

The 25-metre Dwingeloo Telescope (then the largest steerable radio telescope in the world) is opened by Queen Juliana. The telescope maps out the detailed structure of the Milky Way and detects obscured, nearby galaxies Dwingeloo 1 and 2.

The WSRT (Westerbork Synthesis Radio Telescope) is opened by HM Queen Juliana.

The WSRT is being expanded to include two new telescopes, increasing the baseline length to 3 km. This doubles the spatial resolution of the telescope. Cooled receivers are also introduced at 6 and 21 cm.

The Digital Spectral-Line (DSL) multi-channel correlator is installed, and the first HI line maps are produced of external galaxies. The WSRT provides the best evidence yet for dark matter in galaxies, demonstrating flat rotation curves far beyond the stellar disk.

The European VLBI Network (EVN) is established with ASTRON as one of its founding members. The WSRT becomes a major component of the network, building on the first EVN experiment (1976) using the “ODE” network – Onsala (SE), Dwingeloo and Effelsberg (DE).

The UK-NL research collaboration is signed, leading to ASTRON playing a leading role in the design and construction of instruments for optical telescopes and the new sub-mm James Clerk Maxwell Telescope. This later leads to the establishment of the NOVA Optical/IR Group at ASTRON.

ASTRON is at the forefront of conceiving the original concept of the Square Kilometre Array – this will later emerge as one of the most ambitious global mega-science projects of the 21st century.

The Joint Institute for VLBI in Europe is established, hosted by ASTRON. The EVN Correlator is formally opened in 1998.

ASTRON embarks on a major new R&D line, developing Aperture Arrays for Radio Astronomy. This has a major impact in the development of several next generation radio telescopes, including LOFAR and the SKA.

A major upgrade of the WSRT is completed. This includes the deployment of the new Multi-Frequency Front Ends (MFFEs). These provide broad-band frequency flexibility from 1 tot 8.4 GHz.

ASTRON’s first Phased Array Feed prototype, FARADAY is deployed and tested on the WSRT.

ASTRON becomes the Netherlands Institute for Radio Astronomy – returning to its original mission: “Making Discoveries in Radio Astronomy Happen!”

LOFAR is opened by HM Queen Beatrix.

Opening of ASTRON’s new building by State Secretary, Drs. Sander Dekker.

The SKA telescope is under construction.