Could life exist on a dwarf planet?
Three things are needed for life: liquid water, an energy source and organic molecules – that is, molecules containing carbon.
More than 100 miles (161 kilometers) below Pluto’s surface, an enormous ocean of liquid water may exist; this might also be true for other Kuiper belt worlds. Ceres also has subsurface water, remnants of what might have been an ancient global ocean.
Organic molecules, in abundance everywhere in our solar system, have been found on Ceres and Pluto.
But the one missing ingredient for all the dwarf planets is a source of energy.
Sunlight won’t work, particularly for the Kuiper belt dwarfs; they are simply too far away from the Sun. To reach the belt, the light must travel more than 2.7 billion miles (4.4 billion km). By the time the sunshine arrives at these distant worlds, it’s too weak to significantly heat any of them.
And all the dwarf planets are too small to hold the inner heat that remains from the solar system’s formation.
Yet scientists have discovered life on Earth in the most hostile places imaginable – near the bottom of the ocean, miles deep in the soil and even inside an active volcano. When it comes to life in our solar system, never say never.
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Vahe Peroomian, Professor of Physics and Astronomy, USC Dornsife College of Letters, Arts and Sciences
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