Helioseismic measurements of solar radius changes from SOHO/MDI

S. Lefebvre, A. G. Kosovichev, J. P. Rozelot

Research output: Chapter in Book/Report/Conference proceedingConference contribution

1 Scopus citations


We report on the changes of the Sun's subsurface stratification inferred from helioseismology data. We used SOHO/MDI (SOlar and Heliospheric Observatory/Michelson Doppler Imager) /-mode frequencies and their temporal variation for the last 10 years to compute the variation of the radius in the subsurface layers of the Sun by applying helioseismic inversions. We have found a variability of the "helioseismic" radius in antiphase with the solar activity, with the strongest variations of the stratification being just below the surface around 0.995R. Besides, the radius of the deeper layers of the Sun, between 0.975 R and 0.99 R changes in phase with the 11-year cycle. These results imply a non-homogeneous variation of the radius with depth and time.

Original languageEnglish (US)
Title of host publicationProceedings of SOHO-17
Subtitle of host publication10 Years of SOHO and Beyond
StatePublished - Jul 1 2006
Externally publishedYes
EventSOHO-17: 10 Years of SOHO and Beyond - Sicily, Italy
Duration: May 7 2006May 12 2006

Publication series

NameEuropean Space Agency, (Special Publication) ESA SP


OtherSOHO-17: 10 Years of SOHO and Beyond

All Science Journal Classification (ASJC) codes

  • Aerospace Engineering
  • Space and Planetary Science


  • Sun: activity
  • Sun: helioseismology
  • Sun: interior
  • Sun: oscillations

Cite this

Lefebvre, S., Kosovichev, A. G., & Rozelot, J. P. (2006). Helioseismic measurements of solar radius changes from SOHO/MDI. In Proceedings of SOHO-17: 10 Years of SOHO and Beyond (617 ed.). (European Space Agency, (Special Publication) ESA SP; No. 617).