The inner solar system with a visiting comet

This artist's rendition illustrates the formation of rocky bodies in the solar system - how they form and differentiate and evolve into terrestrial planets

An artist's rendering of a fledgling solar system.

The giant asteroid Vesta is shown here as the smallest body among other similar bodies in the solar system: Mars, Mercury, Earth's moon and the dwarf planet Ceres.

Astronomers at the European Southern Observatory in Chile have discovered a planetary system similar to our solar system with up to seven planets orbiting a sunlike star

An artist's rendering of the latest planet discovered orbiting 55 Cancri, which is part of a solar system similar to Earth's.

The distant exoplanet TrES-2b, shown here in an artist's conception, is darker than the blackest coal. This Jupiter-sized world reflects less than one percent of the light that falls on it, making it blacker than any planet or moon in our solar system.