On Wednesday, July 15, 2015, NASA released the first close images of Pluto recently taken by the New Horizons space probe. What the photos revealed was a shock to conventional uniformitarian scientists who believe in a 4.5-billion-year-old solar system. Over the past half century, planetary scientists have become accustomed to finding many impact craters on the surfaces of bodies in the solar system. However, from the preliminary photos of Pluto's surface, these scientists have found far fewer craters than they expected. Earlier wide-field views of half of Pluto's surface seem to indicate a few craters, but the first close-up region examined appeared to have no craters. Craters appear to be the results of collisions with smaller bodies. Most scientists think that the solar system formed approximately 4.5 billion years ago, so they interpret craters in terms of their accumulation during that time. Supposedly, many of the impacts were from leftover material that did not form into planets. If true, then the rate at which craters formed was much greater in the early solar system than it is today. Some surfaces, such as Earth's and Jupiter's satellite Io, have relatively few craters. Planetary scientists explain this by geological processes that remove or cover craters. On Earth, the main geological processes responsible for this are believed to be the sedimentation and igneous activity accompanying plate tectonics, and weathering and erosion. On Io, the principle mechanism of crater removal is volcanism — Io has many active volcanoes that change the surface regularly. Some surfaces of solar system bodies, such as Earth's moon, have regions of high crater density and regions of low crater density. This is explained by volcanism that affected parts of them, such as on our moon, and not others.