Expansion Planner
Expansion Planner (interface) in the Stellaris encyclopedia: The Expansion Planner lists Planets that present opportunities for colonization. Colonization can be started directly from this screen, which automatically builds a Colony Ship.
Expansion Planner in the game's words
The encyclopedia entry as the game shows it in its tooltips; underlined words open their own entry or page here.
The 
Expansion Planner lists 
Planets that present opportunities for colonization. Colonization can be started directly from this screen, which automatically builds a 
Colony Ship.
Planets must be surveyed by a 
Science Ship and any 
Anomalies found on the planet must be investigated before the planet can be colonized.
A Starbase must also have been constructed in the planet's system, so that it lies within the empire's borders.
Entries that mention Expansion Planner
More in Interface
Source: common/game_concepts (concept_expansion_planner) and localisation/english, Stellaris Cygnus v4.5.2 (9776).