Photos: Red Spot Jr. grows on Jupiter

This series of photos shows how the storm grew. In 1997, three separate storms were seen. In 1998, two. Then, in 2000, the remaining two storms combined.

The Great Red Spot is a storm on Jupiter that has been raging for at least 400 years. Three Earths can fit into the storm, which is similar to a hurricane. The storm was active when humans first observed the planet with a telescope.

Astronomers do not know why the Red Spot is red, but one theory says that the storms scoop up red materials from beneath Jupiter's clouds.

The Hubble Space Telescope has a long history of capturing spectacular events on Jupiter. On July 24, 1994, the Hubble grabbed headlines with pictures of the Comet Shoemaker-Levy breaking up and then crashing into Jupiter. There are eight crash sites in this photo.

A solar eclipse is rare on Earth, but this photo shows three occurring at the same time on Jupiter.

In this Hubble image, three of Jupiter's 16 confirmed moons cast shadows that create black spots. From left to right, they are cast by Ganymede, Io and Callisto.

Two of the moons are also visible in this image. Io is the white spot toward the center of the planet; Ganymede is the blue spot in the upper right. Callisto is outside the frame.