Makeb’s +10 to Endurance datacron
The starting location (marker is orange) is on Frinn Mesa. The datacron itself takes you to the Cartel Mining Mesa (marker is green). Both locations can be seen on the Makeb world map.
Makeb’s +10 to Presence Datacron
Both the starting location (marker is orange) and the datacron (marker is green) are on Perekta Mesa, in the south-west part of Makeb.