In the battle of satellites versus stars, the motion of constellations of satellites will draw the eye and drown out the quiet background stars.

On September 29 and 30, 2021, use the waning crescent moon in Gemini to find the stars Castor and Pollux in the predawn sky.

Mars was once a wet and habitable world, so what happened to change that? According to a new study from Washington University in St. Louis, Mars' small size is likely to blame for why it lost most of its water and atmosphere.

Einstein's most famous equation describing the relationship of energy and mass, E=mc², first appeared in a scientific journal on September 27, 1905.

Hear the sounds of space. The videos in this post are what happens when scientists turn astronomical data into sound, via a process called sonification.

As we view Saturn from Earth over years, our perspective changes. Sometimes see the north face of the rings, and sometimes the south face.

Late at night on these next several nights - September 25, 26 and 27, 2021 - watch for the moon, Aldebaran, Pleiades.

EarthSky readers shared two amazing September deep sky photographs with us: the Cygnus Loop, a nebula that stretches into Vulpecula, and Bode's Galaxy, aka M81.

NASA scientists say that there were once thousands of volcanic eruptions on Mars. These explosive blasts, in the northern Arabia Terra region, were "super eruptions," the largest and most powerful kind known. The intense activity continued for about 500 million years, about four billion years ago.

The Juno spacecraft observed footprint tails of aurora on Jupiter’s atmosphere. Three of Jupiter’s closest large moons create these auroral tails.