Dawn spacecraft prepares to take more photos of dwarf planet Ceres
NASA announced on Monday, April 6, that the Dawn spacecraft has performed flawlessly in the month since its capture by the gravity of the dwarf planet Ceres. Ceres’ gravity, in combination with the thrust from Dawn‘s ion engine, is guiding the spacecraft into a circular orbit around the tiny world. All of the spacecraft’s systems and scientific instruments are in excellent shape.
Since early March, Dawn has been following its planned trajectory on the side of Ceres facing away from the Sun. After the spacecraft entered orbit around Ceres, its momentum carried it into a higher altitude, reaching a maximum of 46,000 miles (74,030 km) on March 18. On Monday, Dawn was about 26,000 miles (41,843 km) above Ceres as it descended towards its first planned science orbit, which will be approximately 8,400 miles (13,518 km) above the surface.
Dawn‘s next optical navigation photographs of Ceres will be taken on April 10 through April 14. The images are expected to be available online after Dawn‘s science team completes their initial analysis. In the 10 April images, Ceres will appear as a thin crescent, much as it did in images taken on March 1, but with about 1.5 times higher resolution. The 14 April images will reveal a slightly larger crescent in more detail. Dawn will begin its intensive prime science campaign when it settles into its first science orbit on April 23.
These photos should provide an improved view of the entire surface of Ceres by early May. Two mysterious bright spots that have appeared in earlier images have captured the imaginations of both researchers and space enthusiasts alike. It is still unknown what these reflections of sunlight represent, but closer images should yield more information about their nature. These objects were of particular note to scientists who commented on them this past February.
“The brightest spot continues to be too small to resolve with our camera, but despite its size it is brighter than anything else on Ceres. This is truly unexpected and still a mystery to us,” said Andreas Nathues, lead investigator for the framing camera team at the Max Planck Institute for Solar System Research, Gottingen, Germany.
While the regions containing the bright spots most likely will not be in view for the 10 April image, it is not known for certain whether they will be in view for the 14 April image pass.
Dawn is scheduled to complete its first Ceres science phase on May 9 and begin a spiral descent to a lower orbit to observe the dwarf planet from a closer perspective.
“Since its discovery in 1801, Ceres was known as a planet, then an asteroid and later a dwarf planet,” said Marc Rayman, Dawn chief engineer and mission director at JPL. “Now, after a journey of 3.1 billion miles (4.9 billion kilometers) and 7.5 years, Dawn calls Ceres, home.”
Dawn’s scientific instrument payload consists of two cameras, a visible and infrared mapping spectrometer to reveal the surface minerals, and a gamma ray and neutron spectrometer to determine the elements that make up the outer parts of the asteroids. Scientists will use the data from these systems to study surface features and the complex and varied landscapes of the Dawn mission’s two target worlds.
The Dawn spacecraft launched from Launch Complex 17B at Cape Canaveral Air Force Station in Florida on Sept. 27, 2007. The spacecraft, equipped with an ion engine, arrived at its first target, the asteroid Vesta on July 16, 2011. Dawn explored Vesta for 14 months, capturing detailed images and data about the asteroid. The spacecraft departed for Ceres, the mission’s second target, on September 5, 2012. Dawn began orbiting Ceres on March 6, 2015. The probe is the first spacecraft to orbit a body in the main asteroid belt as well as the first spacecraft to orbit two targets.
Video courtesy of NASA / JPL
Jim Sharkey is a lab assistant, writer and general science enthusiast who grew up in Enid, Oklahoma, the hometown of Skylab and Shuttle astronaut Owen K. Garriott. As a young Star Trek fan he participated in the letter-writing campaign which resulted in the space shuttle prototype being named Enterprise. While his academic studies have ranged from psychology and archaeology to biology, he has never lost his passion for space exploration. Jim began blogging about science, science fiction and futurism in 2004. Jim resides in the San Francisco Bay area and has attended NASA Socials for the Mars Science Laboratory Curiosity rover landing and the NASA LADEE lunar orbiter launch.