In Metsähovi we monitor the Sun's activity with several radio telescopes and antennas. We aim to have daily solar maps at 37 GHz using the 14-metre radio telescope in order to track the development of active areas on the Sun. During the summer time (April-September) the large radio telescope is used more extensively for solar observations: for example, we can follow a single radio brightening for several hours, or coordinate multifrequency sessions with other instruments.
Our 1.8-metre radio telescope is dedicated to follow the Sun throughout the day, every day, continuously recording the total intensity at 11.2 GHz. At the same time, we use several antennas to record the solar UV levels as well as a full spectrum of low frequencies between 50-850 MHz.
The smaller radio telescope is especially suited for investigating solar radio burst features. Metsähovi belongs to the international e-Callisto network which aims at observing solar radio bursts at a broad frequency range at several locations around the world simultaneously. The two Callisto antennas attached to the dish measure broadband solar radio bursts at meter and decimeter ranges, 50-850 MHz.
During the summer time, due to the Northern location of Metsähovi, we are able to do even 14-hour continuous solar observations. This ability is remarkable and brings a peculiar twist to our observations. The long time series measured at Metsähovi (since 1978) enables studying long term alterations (so-called cyclicity studies) in the Sun, for example, by investigating solar radio brightenings. Long measurements observed during a single day can be used for studying short term changes (so-called oscillation studies) in different structures (for example, radio brightenings and polar region brightenings). In addition, the versatile radio burst data is analyzed for single bursts and for statistical reasons.