Frédéric Clette

TL;DR: The Extreme-ultraviolet Imaging Telescope (EIT) as discussed by the authors provides wide-field images of the corona and transition region on the solar disc and up to 1.5 R⊙ above the solar limb.

TL;DR: In this article, the authors present a global overview of the current understanding of the sunspot number calibration process and present a series of dedicated Sunspot number workshops, including the Sunspot Number Workshops.

TL;DR: In this article, the authors present a global overview of the current understanding of the sunspot number calibration and propose an epochal revision of the Sunspot Number, the first one since Wolf himself, and its reconciliation with the Group Number, a long-awaited modernization that will feed solar cycle research into the 21st century.

TL;DR: The Extreme Ultraviolet Imaging Telescope (EIT) on board the SOHO spacecraft has been operational since 2 January 1996 and has been used to observe the Sun over a 45 × 45 arc min field of view in four emission line groups: Fe IX, X, Fe XIIi, Fe xv, and He II.

TL;DR: In this article, the authors make an inventory of the transients observed in the EIT image sequence and discuss in full detail the morphology and evolution of several typical events, such as B3.5 and footpoint brightenings.