Each mark is one catalogued solar-system object on one night, kept only when that night has at least three detections. The brightness of the map is how many of those tracklets fall in a 0.1° cell. A faint line joins consecutive nights of the same labelled object. Click a line and that object's whole trail turns red. It is a map of the catalogue, not a picture of the sky. Drag to move, scroll to zoom. Individual nights appear once the view is narrower than 8°. Click one to play its detections.
Right ascension increases to the right and declination upward, in equal degrees. Offsets in the night panel are on the sky: Δα cos δ and Δδ, in arcsec, from the fitted position. Source: DP2 DiaSource rows with an ssObjectId, MJD 60790–61047.