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Explanation: Informally named Wright Mons, a broad mountain about 150 kilometers across and 4 kilometers high with a wide, deep summit depression is featured in this inset image captured during the New Horizons flyby of Pluto in July 2015. Of course, broad mountains with summit craters are found elsewhere in the Solar System, like the large shield volcano Mauna Loa on planet Earth or giant Olympus Mons on Mars. New Horizons scientists note the striking similarity of Pluto's Wright Mons, and nearby Piccard Mons, to large shield volcanoes suggests the two could be giant cryovolcanoes that once erupted molten ice...

Explanation: Is there anything interesting to see in the direction opposite the Sun? One night last month, there were quite a few things. First, the red-glowing orb on the lower right of the featured image is the full moon, darkened and reddened because it has entered Earth's shadow. Beyond Earth's cone of darkness are backscattering dust particles orbiting the Sun that standout with a diffuse glow called the gegenschein, visible as a faint band rising from the central horizon and passing behind the Moon. A nearly horizontal stripe of green airglow is also discernable just above the horizon, partly blocked...