Launched by Japan in 2003, the Hayabusa capsule has traveled 2.5 billion miles (4 billion kilometers) in seven years and landed twice on an asteroid, where it collected samples. It is expected to return to Earth shortly, carrying with it a cargo of asteroid material that scientists plan to study. The samples are expected to offer researchers insights into how and when the asteroid was formed, its physical properties, what other bodies it may have come into contact with, and how it has been affected by solar wind and radiation.