Periodic Comet 46P/Wirtanen is now the brightest comet in the night sky, but too faint to be seen by eye.

What's inside this cosmic cave? A stellar nursery 10 light-years deep.

Could this close-by asteroid ever hit the Earth? Eventually yes -- but probably not for a very long time, even though the asteroid is expected to pass inside the orbit of the Moon next century.

The majestic Lagoon Nebula is filled with hot gas and the home for many young stars.

What would it be like to explore the Moon? NASA's Apollo missions gave humans just this chance in the late 1960s and early 1970s.

Tonight the Moon is young again, but this stunning image of a young Moon near the western horizon was taken just after sunset on October 10.

Don't panic. This little planet projection looks confusing, but it's actually just a digitally warped and stitched, nadir centered mosaic of images that covers nearly 360x180 degrees.

This composite of images spaced some 5 to 9 days apart, from late April (bottom right) through November 5 (top left), traces the retrograde motion of ruddy-colored Mars through planet Earth's night sky.

Dark shapes with bright edges winging their way through dusty NGC 6188 are tens of light-years long.

There's even a California in space. Drifting through the Orion Arm of the spiral Milky Way Galaxy, this cosmic cloud by chance echoes the outline of California on the west coast of the United States.