Per the SOHO website, SWAN
- is designed to observe photons ... backscattered. ... Because SWAN observes backscattered photons, it is actually possible to 'see' those which are originating from the farside of the Sun.
- Far Side Imaging
- can be processed in order to reveal bright points in ultraviolet light by subtracting an average hydrogen glow. When the maps are displayed in ecliptic coordinates any point seen moving on an image sequence is potentially a comet.
Comet Trackers Maps
SWAN presents a surround view in the Comet Tracker Maps, the dark areas representing the Sun itself. Since this is a picture drawn in photons and ultraviolet light and hydrogen glow, we need to compare the unusual orbs presenting during November, 2004 (boxed below) to other objects that appear on SWAN.