NASA’s Dawn Spacecraft Closes in on Dwarf Planet
The Dawn spacecraft by NASA is closing in on the dwarf planet Ceres and is entering its approach phase. The spacecraft launched to space back in the year 2007 and will enter Ceres’ orbit by March of 2015. Ceres is a dwarf planet comparable in size to Texas and no spacecraft has ever visited it before.
The spacecraft has just recently escaped from solar conjunction, which means that the Dawn is on the opposite side of the sun making it impossible for any communication with Earth. Now that communication has been restored, mission controllers are now programming the required maneuvers in space needed to enter the next stage which they call the Ceres approach phase. Currently, the spacecraft is 640,000 km or 400,000 miles away from the dwarf planet and is traveling at roughly 725 km/h or at a rate of 450 mph.
With the Dawn’s arrival at Ceres, this will be the very 'first' time that a 'spacecraft' has entered orbit for two objects in our solar system. Previously, the spacecraft orbited around Vesta, a protoplanet, from 2011 to 2012 for 14 months. The craft has sent back valuable and detailed photos and data from Vesta.
Shedding Light into the Mysterious Dwarf Planet
Christopher Russell is one of the principal investigators of the Darm Mission and is based at the University of California in Los Angeles. According to him, the dwarf planet Ceres is a complete mystery right now since unlike the protoplanet Vesta, there are no meteorites that are linked to it which can be used to help reveal some of its mysteries.
Both planetary bodies are important to scientists in differing ways. It is thought that Vesta formed earlier than Ceres which has a cooler interior. Also, evidence points to Vesta retaining only a small amount of water since it formed first, thus having more radioactive material which would produce more heat. On the other hand, Ceres has a thick mantle made of ice. It may even be possible for it to have an ocean underneath its icy crust.
In the 'next' couple of months, images of Ceres will continue to improve as Dawn slowly approaches the target. By the end of the month of January, NASA will be receiving the best images of Ceres that they have ever had. 'JPL', a 'division' of the 'California Institute of Technology' in Pasadena manages the Dawn mission to both Ceres and Vesta for NASA's 'Science Mission' Directorate, Washington. For the whole Dawn mission, UCLA is the one responsible for it.
The Dawn spacecraft makes use of ion propulsion to travel across space. This method is a lot more efficient as compared to chemical propulsion which enabled it to complete roughly five years in accumulated thrust time which far exceeds any spacecraft. Ceres has an average diameter of 950 km or 590 miles and is the largest space object in the 'asteroid' belt which is a band of asteroid in the solar system that is located between the planets Mars and Jupiter. In comparison, the protoplanet Vesta has an average diameter of 525 km or 326 miles and is the second biggest object in the belt.
Image credit: NASA / JPL (Wikimedia Commons)