Pluto is very small (radius 1,185 km), and very far away (about 7.5 billion km from Earth).

Being able to take a photograph of it is a significant achievement. Being able to show features of the landscape? It's amazing.

Here's a nice page that describes a demonstration of the distance to scale.

http://www.noao.edu/education/work/Peppercorn/Peppercorn_Mai...