The flight has a relatively narrow 13-minute window. If it can't make that, there will be a backup window on June 13th at the same time of day.

The RADARSAT Constellation Mission involves three synthetic aperture radar satellites that will supply considerably more advanced Earth observation data than the earlier, single-satellite RADARSAT-2. It'll not only help cover Canada's vast territory more effectively, but will also supply "daily" coverage of 90 percent of the world's surface. That in turn will help scientists in Canada and elsewhere track environmental traits like climate change and human land use. This mission may be relatively routine as far as SpaceX is concerned, but it could be useful to the whole planet.