SCIAMACHY's passage through the dayside and the nightside zones every ~100 minutes typically allows the following sequence of measurements:

Fig 1.3.2.2.1: SCIAMACHY measurement sequence overview.

Image courtesy of :

• Pre-sunrise: The orbit starts with limb measurements prior to sunrise.
• Sunrise: A solar occultation mode stage, which takes place during the sunrise that SCIAMACHY sees as it passes from the nightside to the dayside phase.
• Dayside: A scanning stage, consisting of alternating limb/nadir mode scans of the atmosphere.
• Moonrise: A lunar occultation mode stage, which takes place on the 5–8 days of the 28 day lunar cycle on which SCIAMACHY experiences a 'moonrise' as it passes from the dayside into the nightside.
• Nightside: A number of calibration and radiance measurements conducted during the passage through the nightside.

These stages are discussed in greater detail in the following sections.