1983    ''Pioneer 10'' becomes the first man-made object to leave the solar system.

1989    Voyager 2 spacecraft makes its closest approach to Neptune, the outermost planet in the Solar System.

2005    Eris, the largest known dwarf planet in the solar system, is discovered by the team of Michael E. Brown, Chad Trujillo, and David L. Rabinowitz using images originally taken on October 21, 2003, at the Palomar Observatory.

2005    An intense solar flare blasts X-rays across the solar system.