Dwingeloo (astronomy)

Largest in the World

When it becomes operational on 17 April 1956, the Dwingeloo Radio Observatory, also called the 'DRT', is the largest in the world. The dish has a diameter of 25 metres and the whole structure weighs as much as 120 tonnes. The one-million dollar observatory was built by Werkspoor and Philips, in collaboration with a number of universities.

Impressive Structure

The large dish, called a 'parabolic reflector' or 'mirror' in technical terms, stands on four wheels that run along a track. The track has been placed atop a concrete foundation. The mirror can be rotated using three motors. Through an axis, all the cables enter the structure. A box is mounted in front of the mirror, containing the receiver equipment. A small building stands behind the dish. This houses the computers that process all the data that is collected.

Neutral Hydrogen

The DRT was used by scientists to map neutral hydrogen in the Milky Way. The observatory also discovered two smaller galaxies near the Milky Way. They were given the names Dwingeloo 1 and Dwingeloo 2. After 1998, the observatory was no longer operational. For years it wasn't well maintained.

National Heritage Site

The poorly maintained observatory was made a National Heritage Site in 2009. Manager ASTRON had the observatory recognised as an industrial heritage monument in 2010. The government granted a subsidy in 2011 to restore the telescope. On 5 April 2014, the telescope was reopened in the presence of American astrophysicist and Noble Prize winner Joseph Hooton Taylor.

Go Discover

You can visit the radio observatory yourself. The entry is located in the Mullerhuis at Oude Hoogeveensedijk 6 in Dwingeloo.

Photo: Joop van Bilsen / Anefo – opening of DRT by Queen Julia 17 April 1956.
Photo: RCE Beeldbank 10774-8246 – maintenance of DRT
Photo: RCE Beeldbank 530829 – maintenance of DRT