Very Long Baseline Interferometry (VLBI)
The angular resolution of this sophisticated but technologically very demanding observing technique exceeds that of any other available instruments. In active galaxy research in particular the extremely high angular resolution is crucial in understanding the extreme physics related to supermassive black holes.
Three VLBI user communities make use of the Metsähovi telescope:
- European VLBI Network (EVN) for 22 GHz and 43 GHz astronomical VLBI observations,
- Global Millimetre-VLBI Array (GMVA) for 86 GHz astronomical observations, and
- International VLBI Service for Geodesy and Astrometry (IVS) for 2 + 8 GHz geodetic VLBI.
The latter project is carried out in Metsähovi as part of a research contract with the National Land Survey and the Finnish Geospatial Research Institute. In this observing mode the focus is on determining Earth's rotation parameters and the relative positions of the participating radio telescopes with millimetre-accuracy. This makes is possible to study e.g. continental movements and Earth's crustal dynamics with extreme accuracy. These measurements are integral to defining national coordinate systems, enabling satellite navigation, etc.
Additionally, Metsähovi frequently participates in VLBI experiments involving high-speed data transfer tests, or projects observing specific Target-of-Opportunity projects (fast radio bursts, tracking the signal of a planetary probe, detecting water in the vicinity of Saturn, etc.). Metsähovi is one of the few observatories in the world capable of this kind of flexibility: the telescope schedule can easily be changed on demand when new scientific or technical breakthroughs are anticipated, or at least an opportunity to explore beyond the conventional “proposal-writing science” is called for.
For technical details etc., please contact [email protected] .