PASADENA, California - The Dawn spacecraft has begun collecting data about the asteroid Vesta.

The NASA probe made its first detailed observations of the surface Thursday from a distance of 2,735 kilometres and will spend the next several weeks taking images from that altitude. Afterward, it will spiral closer to the asteroid to get a better view.

Dawn slipped into orbit around Vesta last month after a four-year journey and beamed up early pictures revealing a rocky body with radically different northern and southern hemispheres.

Vesta resides in the asteroid belt between Mars and Jupiter. Scientists hope to better understand the conditions of the early solar system by studying asteroids.

Dawn will circle Vesta for year before moving on to a bigger asteroid, Ceres, where it will arrive in 2015.