Instead, NASA extended the University of Arizona-led mission so that the spacecraft can be used to study another near-Earth asteroid named Apophis. The mission was renamed OSIRIS-APEX, short for OSIRIS-APophis EXplorer. An overview of the mission was published in the
The spacecraft will catch up to the asteroid on April 13, 2029, as the asteroid wizzes 20,000 miles above Earth’s surface. Scientists will then spend the next 18 months studying the asteroid in detail. They’ll also disturb the material on the surface with the spacecraft to reveal what lies just beneath.“Apophis is an infamous asteroid,” said DellaGiustina, who is an assistant professor of planetary sciences at the University of Arizona’s Lunar and Planetary Laboratory.
“We know that tidal forces and the accumulation of rubble pile material are foundational processes that could play a role in planet formation. They could inform how we got from debris in the early solar system to full-blown planets. Our best guess right now is that Apophis is, indeed, a rubble pile.”