Dawn (from an Old English verb dagian "to become day") is the time that marks the beginning of the twilight before sunrise. It is recognized by the presence of weak sunlight, while the Sun itself is still below the horizon. Dawn should not be confused with sunrise, which is the moment when the leading edge of the Sun itself appears above the horizon.
Two studies conducted by scientists at NASA based on data gathered by the Dawn spacecraft, which orbited around the Vesta asteroid, showed that the giant space rock holds tantalizing signs of water on its surface – albeit in very small amounts, in the form of hydrated minerals. These conclusions were drawn after scientists found that volatile, or easily [...]
It’s one asteroid down and one to go, for NASA’s Dawn spacecraft. After spending a year studying the Vesta asteroid and retrieving valuable information to Earth, Dawn is now ready to head for its next destination: Ceres. A different world Scientists expect Ceres to be very different from Vesta. Ceres is considered to be the [...]