Top: The northern hemisphere of the Sun, with two sigmoids.
15 May 1998 10:47 UT.
Bottom: A sigmoid before (left, 8 June 1998 15:19 UT)
and after (right, with cusp, 9 June 1998 16:17 UT) an eruption
has taken place.
Solar X-ray image from the
Yohkoh Soft X-Ray Telescope.