Why 3 September?
The choice of 3 September for lunar impact was led by the decision to obtain further high resolution lunar data from orbit and to allow ground telescopes to see the impact from Earth. On 3 September 2006 the SMART-1 perilune, coinciding with the point of impact, will be on the lunar area called Lake of Excellence, located at mid-southern latitudes. This area is very interesting from the scientific point of view. It is a volcanic plain area surrounded by highlands, but also characterised by ground mineral heterogeneities. At the time of impact, this area will be in the dark on the near-side of the Moon, just near the terminator the line separating the lunar day-side from the night-side. The region will be shadowed from the Suns direct rays, but it will be lit faintly by the light from the Earth by earthshine. The spacecrafts orbit will take it over the region every five hours, getting one kilometre lower at each pass. From Earth, a Moon quarter will be visible at that time. This geometr
