124
Collados et al. 2013) and Solar Orbiter satellite (Mueller et al. 2020) promise a great
leap in our understanding of these topics.
7.2 The Fundamental Nature of Solar Structures
Secchi’s daily observation of the solar surface revealed intricate patterns and dynamics in sunspots, even at the smallest observable scales (Fig. 7.1).
These observations were mainly conducted by Secchi with a Cauchoix achromatic telescope, equipped with a lens of 17 cm aperture, 238 cm focal length, on an
equatorial fork mount and using a solar projection board. This instrument allowed
Secchi to obtain a white light–projected solar image with a diameter of 246 mm
(Secchi 1859; Altamore et al. 2018).
Fig. 7.1 (a) Drawing of a sunspot region observed by Secchi in 1858; (b) detail of the largest
sunspot of that region; (c) high-resolution spectropolarimetric picture of a sunspot observed at Big
Bear Solar Observatory. (From: Zhang et al. 2018)
I. Ermolli and M. Ferrucci
Collados et al. 2013) and Solar Orbiter satellite (Mueller et al. 2020) promise a great
leap in our understanding of these topics.
7.2 The Fundamental Nature of Solar Structures
Secchi’s daily observation of the solar surface revealed intricate patterns and dynamics in sunspots, even at the smallest observable scales (Fig. 7.1).
These observations were mainly conducted by Secchi with a Cauchoix achromatic telescope, equipped with a lens of 17 cm aperture, 238 cm focal length, on an
equatorial fork mount and using a solar projection board. This instrument allowed
Secchi to obtain a white light–projected solar image with a diameter of 246 mm
(Secchi 1859; Altamore et al. 2018).
Fig. 7.1 (a) Drawing of a sunspot region observed by Secchi in 1858; (b) detail of the largest
sunspot of that region; (c) high-resolution spectropolarimetric picture of a sunspot observed at Big
Bear Solar Observatory. (From: Zhang et al. 2018)
I. Ermolli and M. Ferrucci