Dawn Gets A Close-Up Of An Ex-Planet
The spacecraft closes in on Ceres in March
This month, the Dawn probe will give scientists their first clear view of dwarf planet Ceres. Like many objects in our solar system, it has a checkered past. Astronomers deemed the body a planet, then an asteroid, then a dwarf planet, all in the span of 200 years. The designation isn’t up for debate on this mission. But if history is any guide, the term used to describe a rocky planetoid is still anything but solid.
This article was originally published in the March 2015 issue of Popular Science.