On January 19, NASA released the newest and most detailed photos taken of Ceres by the Dawn spacecraft as it approached the dwarf planet. As the March 6 arrival rendezvous date with Ceres approaches, scientists are growing more and more excited at the prospect of the availability of new and spectacular views of this fascinating object.
Ceres, the largest object in the asteroid belt with its 590-mile diameter, is just the most recent destination for the Dawn spacecraft. After its 2007 launch, Dawn made a stop at Vesta, the second largest body in the asteroid belt. After its July, 2011, arrival, a thorough survey of Vesta was done leading NASA to determine that Vesta was not just a rocky asteroid. Instead, it is a protoplanet (average diameter of 326 miles) in which planet forming forces early in the history of the solar system caused it to form layers similar to the Earth. The Dawn spacecraft took over 30,000 pictures during its stay.
Dawn left Vesta in September of 2012, and is now in its approach phase for its Ceres arrival. Pictures released by NASA are still blurry but there are already indications of some surface features including craters. Ceres is believed to contain a great deal of water and ice and may even harbor an ocean below its surface. With this discovery, Ceres is thought to potentially be habitable for some forms of life.
Image Credit: NASA
At the annual fall meeting of the American Geophysical Union in December, Jian-Yang Li, of the Planetary Science Institute in Tucson, Arizona said, "I don't think Ceres is less interesting in terms of astrobiology than other potentially habitable worlds."
"Ceres is actually the largest water reservoir in the inner solar system other than the Earth," he continued although, he said, it's uncertain how much of that water is ice and how much is liquid.
[Image Credit: NASA]
Some of the water on Ceres may be liquid because of heating taking place from tidal gravitational forces on the planet's structure and, with its distance from the sun a little under three times that of the Earth, it is affected by a reasonable amount of solar heating.
In January of 2014, the Discovery News reported that Ceres is producing water plumes that may provide some sort of an atmosphere. In a paper published in the journal Nature, Michael Küppers of the European Space Agency in Spain and lead author said, "This is the first time water vapor has been unequivocally detected on Ceres or any other object in the asteroid belt and provides proof that Ceres has an icy surface and an atmosphere."
Dawn will first enter orbit around Ceres at an altitude of around 8,400 miles (13,500 km). Over 22 days, the Dawn spacecraft will spiral down to 2,800 miles (4,430 km). Dawn will then make two more orbital stops until it gets to its final altitude above the surface of 235 miles (375 km). At that point, Dawn's fuel will be exhausted and it will become a mechanical "moon" of Ceres.
During this time, NASA's Dawn spacecraft can be expected to produce mountains of exciting and dramatic photos of Ceres, as well as measurements of many of this bodies' characteristics that will be invaluable in unwinding the mysteries of Ceres, the solar system, and the universe itself.
[Featured Image Credit: NASA]