The Norwegian Mapping Authority's Geodetic Earth Observatory, featuring a 20 meter radio telescope, was first established at Hamnerabben in Ny-Ålesund, Svalbard in 1993. Construction of a new facility at Brandal a couple kilometers further north began in 2013, and the new observatory was officially opened in 2018. The new observatory will gradually be phased in, replacing the facility at Hamnerabben.

The new observatory - once fully operational - will be among a handful of the world’s first core sites within the Global Geodetic Observing System (GGOS), co-locating the four space geodetic techniques: Very Long Baseline Interferometry (VLBI), Satellite Laser Ranging (SLR), Global Navigation Satellite System (GNSS) and Doppler Orbitography and Radiopositioning Integrated by Satellite (DORIS).

As such, the observatory will be a fundamental part of a network of stations which define the global geodetic reference frame, and will be crucial to realise GGOS’s ambitious goals of 1 mm accuracy and 0.1 mm/yr stability.

Next-generation technology

The new observatory, which has an estimated cost of about NOK 300 million, features cutting-edge technology, including next-generation VGOS (VLBI Global Observing System), twin telescopes with fast-slewing antennas and a broadband (2-14 GHz) signal acquisition chain.

The telescopes, surrounded by the Brandal lagoon, Cape Mitra and Kings Fjord, are an impressive 13.2 meters in diameter and loom 18 meters above the ground.

Work is currently ongoing to complete installation and testing of the signal acquisition chain. The first broadband feed will be installed in VLBI telescope 2 in summer 2019, and the second will replace the currently installed tri-band feed in VLBI telescope 1 in 2020. The backend equipment is currently undergoing full-scale testing.

NASA cooperation

Concurrently, plans for construction of a state-of-the-art Satellite Laser Ranging (SLR) facility by NASA are being finalized, following the signature of an agreement between NASA and Norwegian Mapping Authority (NMA) in August 2017. An SLR in Ny-Ålesund, with its location at a latitude of 79° N, will be important because it will allow us to observe polar-orbiting satellites, such as ICESat-2, with extremely good coverage.

Final modifications to the SLR building at Brandal will be carried out in spring 2019. The first major components of the SLR system, i.e., the dome, and the gimbal and telescope, will arrive in Ny-Ålesund in autumn 2019 and will be installed by NASA. The current goal is to have all systems up and running in Ny-Ålesund by 2022.

The original geodetic observatory at Rabben, Ny-Ålesund - will gradually be phased out and replaced by the new facility at Brandal. Photo: Bjørn-Owe Holmberg