Recent Magma Heating Might Explain Water on Mars
Magma flows hundreds of thousands of years ago might account for the water on Mars, but scientists do not know if Mars could produce magma that recently.
New Horizons Images Show Fewer Small Kuiper Belt Objects than Expected
High resolution images from New Horizons of the surfaces of Pluto and Charon show ancient craters, but fewer than astronomers expected.
Simulating an Extreme TNO on the Road to Planet Nine
No one knows if Planet Nine will be found, but looking for it has revealed another unusual object in our Solar System.