Observatories on the Moon
Hostile to life, the moon could be a haven for astronomy. Observatories on its surface could yield extraordinarily detailed views of the heavens and open new windows through which to study the universe
Very Large Structures in the Universe
Clusters of galaxies make up enormous superclusters, which alternate in space with immense voids. Such structures were born in the high-energy interactions of the early universe
Centaurus A: the Nearest Active Galaxy
Active galaxies are galaxies that radiate as much as a million times more energy than typical galaxies. The question of what powers the radiation is studied by observations of Centaurus A