Comet ISON was punier than previously thought
![](https://i0.wp.com/www.sciencenews.org/wp-content/uploads/2013/12/comet-ison-from-mars-mro_free.jpg?fit=860%2C460&ssl=1)
NASA’s Mars Reconnaissance Orbiter captured comet ISON from 8 million miles away on September 29. While less spectacular than other images, the photos helped scientists improve estimates of the comet’s size.
University of Arizona/JPL/NASA