This psychedelic image of the sun from NASA's Solar Dynamics Observatory is actually two pictures combined, both taken on July 12. It's also one of National Geographic News's favorite recent space images.
By superimposing an extreme-ultraviolet image of arcing solar material on a "magnetogram" showing magnetic fields, scientists created a complex picture of an active region just before it unleashed a powerful solar flare.
According to NASA, such composite images help scientists better understand the origins and causes of the flares.
As seen from Turkey, the crescent moon nearly eclipses Jupiter—with Venus soon to follow—during a July 15 conjunction, when celestial objects appear to get close to each other in the sky.
Conjunctions exist only in our heads. Celestial bodies appear to fall in line due to our location in the solar system—they're not actually any closer, or farther, from each other than at any other time.
Seeming to trace a celestial highway, Mars progresses along a retrograde loop in a composite picture made of more than 40 shots taken between October 2011, and July 2012. A retrograde loop occurs when a planet's orbit reverses direction.
Photographer Tunç Tezel created the image from photos he took in Turkey. With his brother's help, Tezel has photographed each of Mars's retrograde paths since 1994.