Solar spicules as imaged by NASA's Solar Dynamics Observatory (NASA) There’s one recurring question I’ve been asking for nearly a decade: Why is the Sun’s corona (its atmosphere) so hot? When asking this out loud I inevitably get the sarcastic “um, because the Sun is…...

Guest article by Dr. Mario M. Bisi (Research Focus) A cut in the ecliptic plane through a 3D reconstruction on 08 November 2004 at 0000 UT using white-light data from SMEI. The view is from directly North of the ecliptic; the Sun is at the centre marked by a +, the Earth is on the right marked with a...