He also made seminal contributions to a broad range of astronomical topics, among them: classifying galaxies and understanding galaxy formation and evolution.

Massive galaxies are considered to be at the pinnacle of galaxy formation because their growth relies on the destruction of smaller galaxies.

By studying infrared light, it will be able to see through the clouds of dust that obscure the astronomer's view of star and galaxy formation.

In my field, we call this framework the “hierarchical scenario” of galaxy formation because it represents a hierarchy of galaxies: the more massive ones grow by devouring smaller ones.

This would then mean that current theories of galaxy formation and evolution greatly over-predict the number of mergers in the past few billion years.