On November 11, 2019 the Sun was mostly quiet, experiencing a minimum in its 11 year cycle of activity. In fact, the only spot visible was actually planet Mercury, making […]

The small, dark, round spot in this solar close up is planet Mercury. In the high resolution telescopic image, a colorized stack of 61 sharp video frames, a turbulent array […]

The history of the Moon is partly written in its craters. Pictured here is a lunar panorama taken from Earth featuring the large craters Langrenus, toward the left, and Petavius, […]

Tomorrow — Monday — Mercury will cross the face of the Sun, as seen from Earth. Called a transit, the last time this happened was in 2016. Because the plane […]

On May 25, 1961 U.S. president John Kennedy announced the goal of landing astronauts on the Moon by the end of the decade. By November 9, 1967 this Saturn V […]

One of the last entries in Charles Messier’s famous catalog, big, beautiful spiral galaxy M101 is definitely not one of the least. About 170,000 light-years across, this galaxy is enormous, […]

Why are these galaxies spinning so fast? If you estimated each spiral’s mass by how much light it emits, their fast rotations should break them apart. The leading hypothesis as […]

Stars are battling gas and dust in the Lagoon Nebula but the photographers are winning. Also known as M8, this photogenic nebula is visible even without binoculars towards the constellation […]