The dwarf planet Ceres is 590 miles (950 kilometers) in diameter, or about the size of the state of Texas. Ceres is thought to be a surviving protoplanet, or planetary embryo, formed 4.57 billion years ago in the earliest days of our solar system.
A year on Ceres is 4.6 Earth years long. Ceres rotates every 9 hours and 4 minutes.
At the start of its encounter in early 2015, the Dawn spacecraft took photos of Ceres with greater clarity than any before.
Photos taken when Dawn was 28,600 miles (46,000 km) away from Ceres were used to make this global map. Even at this low resolution, strange features stand out that beg to be explained.
One feature, a huge basin, is relatively flat, with few craters, indicating that it could be relatively young.
In 1772, astronomers deduced from the spacing of the planets' orbits that an undiscovered planet might orbit between Mars and Jupiter. In 1801, Giuseppe Piazzi discovered Ceres. The small body, initially considered a planet, was later called an asteroid. Today it is classified as a dwarf planet.
Ceres is thought to contain as much as 200 million cubic kilometers of water, more than all the fresh water on Earth. Most of this water is thought to be in the form of ice.
Observations from the ESA's Herschel space telescope indicated that Ceres has a thin water vapor atmosphere.
The water could be the result of icy volcanoes on Ceres' surface, or the result of direct sublimation of ice into space.
Some scientists believe that wherever there is liquid water, there is also the possibility of life.
- 7 Strange Facts About Dwarf Planet Ceres
- Dawn Over Ceres - NASA Probe To Arrive At Dwarf Planet | Images and Visualization
- Meet the Solar System's Dwarf Planets