9 Things The New Horizon Probe Has Taught Us About Pluto

4. Its Current Inhabitants Include A Heart, A Whale And A Doughnut

As the surface has come in to sharper focus, we have been able to pick out features of various shapes. The "whale" (Pluto's homage to Hitchhikers' Guide to the Galaxy perhaps?) measures some 1,860 miles across and is one of the darkest regions we have observed.

The doughnut measures around 200 miles across, and at first glance looks very similar to the volcanoes and impact craters observed across the solar system. But, shadows can play tricks on the eyes and scientists are waiting for more detailed images to emerge before making their evaluation of the feature.

One of the largest features on the surface of Pluto appears to be in the shape of a heart or, as some people have pointed out, in the shape of Pluto The Dog. The heart/dog is a big, bright, relatively featureless area that may well be made up of solid nitrogen, methane and carbon monoxide ice as surface temperatures are so low, that these would exist in their solid state on the planet's surface.