Euclid data will enable the study of a broad range of science topics in addition to dark energy, including:

• Clusters of galaxies
• CMB Euclid galaxy survey cross-correlations
• Strong lensing statistics
• Galaxy-galaxy lensing
• Cool brown dwarfs
• Large streams and merger history of galaxies
• Study of resolved stellar populations in the Galaxy and the universe nearby
• Galaxy evolution: galaxies, AGNs, highly magnified high redshift galaxies, study of the primeval universe
• High-z Lyman Break Galaxies
• Supernovae and transients
• Exo-planets