cnn-The Dawn spacecraft mission could answer some of the big questions about the Big Bang, NASA scientists said Monday as they released the latest images from the mission.
Carrying innovative new instrumentation from the Italian and German space agencies, Dawn is providing unprecedented images of the asteroid Vesta, a roughly 4.65 billion-year-old asteroid with twice the surface area of California.
NASA hosted a press conference at its Jet Propulsion Laboratory in Pasadena, California, with panelists that included scientists from Germany and Italy.
According to Holger Sierks, of the Max Planck Society in Germany, the north end of the asteroid alone is "so rich in features, it will keep the science team busy for years."
Photographic maps and color composite images of the asteroid surface will provide hints into the evolution and chemistry on Vesta, revealing key hints about the early solar system and what minerals make up the asteroid.
Composite images are already showing Vesta's surface to be much more dynamic than expected. Enrico Flamini, chief scientist from the Italian space agency, said Dawn will provide a "new view on the beginning of the solar system."
Chris Russell, the project's principal investigator, said that while it will take the higher-resolution images from later in the mission to answer the major questions, progress so far is encouraging. The craters on the asteroid have "features in them that we did not expect," he said, "and we're learning about theses processes that create these features now."
The northern hemisphere of Vesta has many more craters than the southern hemisphere, providing a wealth of information about the asteroid's early history. The southern hemisphere is much smoother, which may be related to an unusual finding at Vesta's south pole: A vast crater with a single mountainous peak in the center.
The asteroid seems to have suffered a large impact from another celestial object, which may also account for a unique set of ridges that follow the asteroid's equator almost perfectly, something scientists have never seen before.
These are all theories for now. Team scientists say their exciting findings mean there is a great deal of work left to be done, but they will continue to keep the public updated as they reach further into the history of our solar system. Russell said they're planning on providing an "image of the day" online once Vesta has provided more information.
The Dawn mission was proposed in 2000 and then launched in 2007 in hopes of providing a better understanding of how the solar system took shape. The spacecraft slowly started to mirror the orbit of the asteroid around the sun. This gradual approach allowed Dawn to enter orbit around Vesta last month at an approach speed of 60 mph, a remarkably slow speed for typical space vehicles.
This gentle entry speed is a key difference of the Dawn mission, chief engineer Marc Rayman said, setting it apart from other interplanetary exploration. It is "very different than what you're accustomed to," he said, "in which a spacecraft comes screaming up to its destination at high velocity, and then executes a whiplash-inducing burn" to slow down and fall into orbit.
Dawn approached Vesta so slowly that the asteroid's gravitational force pulled the spacecraft into orbit, a maneuver so simple that Mission Control was empty when it happened, Rayman said.
The trick is the use of ion propulsion technology. It provides gradual puffs of the element xenon, spending 70% of its voyage gently thrusting toward its destination and making gradual course corrections. The use of a more cost-effective and efficient technology is what will allow Dawn to visit a second destination, the dwarf planet Ceres, in February 2015, a feat Rayman said would have been "truly impossible" without the new technology.
Dawn will continue to orbit Vesta for one year, changing its orbital pattern and location around the asteroid several times, and providing scientists with new information with each new perspective.
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