In the 1960s, spring came to the southern hemisphere of Neptune, the Solar System's outermost gas giant planet. Since Neptune orbits the Sun once every 165 earth-years, it's still springtime for southern Neptune, where each season lasts over four decades. Astronomers have found that in recent years Neptune has been getting brighter, as shown in this Hubble Space Telescope image taken in 2002. This 2002 image shows a dramatic increase in reflective white cloud bands in Neptune's southern hemisphere. Neptune's equator is tilted 29 degrees from the plane of its orbit, about the same as Earth's 23.5 degree tilt, and Neptune's weather seems to be dramatically responding to the similar relative seasonal increase in sunlight, even though sunlight is 900 times less intense for the distant gas giant than for planet Earth.