The Swedish 1-m Solar Telescope continues to produce outstanding results! In the 28 June issue of Nature, a team of researchers from Norway, Germany, UK, and Sweden (Jaime de la Cruz Rodriguez, Uppsala University) report on magnetic solar tornadoes, discovered in data recorded with the SST, such as shown in the image to the left. Magnetic tornadoes resemble tornadoes on the Earth, but have a magnetic skeleton and are hundreds to thousand times larger in cross-sectional area. Although being small compared to the whole Sun, one such observed tornado could occupy the surface area equivalent of Europe or the USA.

 
Magnetic tornado
© Wedemeyer-Böhm
 

 Using the SST data together with data from the Solar Dynamics Observatory (SDO) and numerical simulations, this study demonstrates that the magnetic tornadoes transport energy from the Sun's surface into its uppermost layer, the corona, where they contribute to the heating of the Sun's outer atmosphere. The authors conclude that these magnetic tornadoes may well be a crucial missing piece of a long-standing puzzle in astrophysics: the heating of the outer solar and stellar atmospheres. The picture on the right is computer generated from the numerical simulations and is shown as cover image on the 28 June issue of Nature.

The small-scale structure of the tornadoes could be observed in the solar chromosphere using the exceptional spatial resolution of the SST. By comparing the locations of these tornadoes with observations of the million degree corona from SDO, the authors were able to demonstrate that these tornadoes deposit large amounts of energy in the corona, explaining its heating and large temperature.

 
Magnetic tornado
© Wedemeyer-Böhm
 

Exceptionally large-scale swirling motions at the Sun's surface were first discovered in data from the former 50-cm Swedish solar telescope in 1988, and small-scale swirling motions and tornadoes were first observed at the surface with the SST in 2008 and in the chromosphere (also with the SST) in 2009.

More information can be found here or from Dr. Jaime de la Cruz Rodriguez, Uppsala University (jaime.cruz@physics.uu.se) or Dr. Sven Wedemeyer-Böhm, University of Oslo (sven.wedemeyer-bohm@astro.uio.no). Click on the images for high resolution versions.