Surprising Shifts in Pluto Atmosphere Point to Gravity Waves (Photos)

Unexpected variations in the brightness of Pluto's wispy atmosphere may be caused by gravity waves, scientists say. Newly analyzed images captured by NASA's New Horizons spacecraft, which flew past Pluto last July, show that the dwarf planet's haze layers can change in brightness depending on lighting conditions and viewing perspective. "The brightness variations may be due to buoyancy waves — what atmospheric scientists also call gravity waves — which are typically launched by