Small Scale Stellar Surface Structures

  • Marcello Rodonò
Conference paper
Part of the Astrophysics and Space Science Library book series (ASSL, volume 143)


The principal characteristics of inhomogeneous localized structures, such as starspots and plages, as derived from modelling the rotation-induced modulation of continuum and line fluxes and from Doppler imaging studies are critically reviewed by taking into account the present observational limits. It is shown that the energetic and geometrical characteristics of magnetic activity phenomena on stars overcome by orders of magnitude the corresponding solar phenomena. However they appear to be solar-type as far as it concerns their origin and evolution: active stars have deep convection zones and, possibly, differential rotation, so that a solar-type dynamo can efficiently operate. Nevertheless, in order to detect strictly solar activity signatures on stars, the photometric precision and spectral resolution of stellar observations need to be improved by at least one order of magnitude. The new generation of very large aperture ground-based telescopes (e.g., ESO-VLT) and space telescopes (e.g., Hubble Space Telescope), together with existing radio observatories (e.g., VLA, VLBI), will need to be used.


Differential Rotation Rotational Modulation Hubble Space Telescope Line Flux Stellar Atmosphere 
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Copyright information

© Kluwer Academic Publishers 1988

Authors and Affiliations

  • Marcello Rodonò
    • 1
  1. 1.Catania Astrophysical ObservatoryAstronomy Institute of Catania UniversityCataniaItaly

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