Dawn Spacecraft Working Hard at Vesta

NASA's Dawn spacecraft, which arrived at the asteroid Vesta last month, has officially started its science mission.  Dawn will study the asteroid belt's second largest asteroid from an orbit of about 2700 km, and over the next 20 days will map the entire surface using both images and a detailed spectral analysis.  This data will give scientists on Earth a better understanding of the formation of Vesta, and why it, and the larger asteroid Ceres, never fully developed into planets.

Dawn snapped this picture of Vesta from 41,000 km (NASA/JPL).

Scientists believe that Vesta accreted into a proto-planet between the orbits of Mars and Jupiter beginning about 10 million years after the formation of the solar system.  However, being so close to Jupiter may have disrupted Vesta's formation, leaving it with only enough material to reach a diameter of 530 km - far smaller than even Earth's Moon.

The Dawn spacecraft was launched in 2007 as part of NASA's Discovery Program, which aims to launch focused missions that are heavy on science and cost effective.  Thus far, Dawn has performed perfectly.  If all continues to go well, after a yearlong study of Vesta, Dawn will leave orbit of that asteroid and head to the even more massive dwarf planet, Ceres.  Ceres is also in the asteroid belt, and is believed to have formed under similar circumstances as Vesta.  Dawn should arrive at Ceres sometime in 2015.

Dawn in the clean room prior to launch (NASA).

The study of these asteroids comes at a good time.  Not only will the science gleaned from this mission help us understand the formation of our solar system, and possibly other solar systems, but NASA plans to send humans to an asteroid by 2025.  Studying the magnetic fields, gravitational pull, and geology of asteroids will no doubt come in handy to future human explorers of these rocky worlds.

Read more about the Dawn spacecraft, its science mission, and Vesta.