Mercury will retrograde from Dec. 13 through Jan. 2 in the last of four times it appears to move backward in the sky this year. Every planet has in our solar system has retrograded for at least part ...

Measurements from MESSENGER's MLA instrument during the spacecraft's greater than four-year orbital mission have mapped the topography of Mercury's northern hemisphere in great detail. Credits: ...

Retrograde mean motion resonances occur when orbiting bodies, moving in directions opposite to the dominant sense of motion, experience periodic gravitational interactions that can stabilise their ...

Mercury will retrograde, or appear to be moving backward in the sky, from August 23 through September 15. It's the third of four times Mercury will be moving in retrograde this year. Mercury isn't the ...

Our solar system is in constant motion, with all eight planets — and dwarf planet Pluto — orbiting the sun. Most of those planets are visible from Earth, even to the naked eye. If you track them in ...

Mercury is almost in retrograde. You may have heard people lamenting the astrological phenomenon, blaming their various woes on the planet's movement. But what does it mean for Mercury to be in ...