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A large set of observations of the Sun at 37 GHz is analysed. An association of 99% is found between the regions of brightness temperature depression and the magnetic field inversion lines. Observations indicate a possible existence of “giant cells” with duration of 1-2 years and a longitudinal extension up to 90°.

The rotation of large scale solar magnetic field patterns was studied using quiescent filaments and low temperature regions observed at 37 GHz as tracers.

So far all relativistically boosted jets with superluminal motion have only been detected in normal radio galaxies that have early-type host galaxies. We have now discovered superluminal motion in the Seyfert 1 galaxy III Zw 2, classified as a spiral. Spectral and spatial evolution are closely linked. Since III Zw 2 is part of a sample of so-called radio-intermediate quasars (RIQ), it confirms earlier predictions of superluminal motion for this source, based on the argument that RIQs could be relativistically boosted jets in radio-weak quasars and Seyfert galaxies.

Quasars have been monitored with the Metsähovi Radio Telescope since 1980 at 22 GHz and 37 GHz. During these years we have recorded numerous outbursts in our sample. Some of the outbursts are simple in nature, while others also seem to have fine structure. Can the outbursts be modelled in a simple way?

The monitoring of extragalactic sources with the Metsähovi radio telescope started in 1980. Since then we have made more than 21000 observations at 12, 22, 37, 77 and 87 GHz. Currently we have 84 sources in our sample which should be observed once a month at 22 and 37 GHz. The sample is limited to declinations above −10 degrees. In most cases our sampling is dense enough to cover all the outbursts at these two frequencies, because our earlier observations have shown the timescales of a typical outburst at 22 and 37 GHz to be from 0.3 to several years.

We present some very preliminary results of the multifrequency microvariability campaign of two BL Lac objects OJ 287 and Mk 421 carried out mainly during four days in March 1993. During these four days also IUE was observing these blazars. In this poster we present only a small part of the whole data: radio observations at Metsähovi, CCD observations on La Palma and Heidelberg and UBVRI photopolarimetric observations at Crimea. Because of the very bad global weather conditions and also because of the faintnes of OJ 287 our optical observations were very limited.