The images from this year's "Grand Tour" of the outer solar system have just been released, and they reveal the gas giants and ice giants that are so unlike Mercury, Venus, Earth, and Mars, which are all rocky planets.

These gas giants, which range in distance from 500 million to 3 billion miles from the Sun, are as far as they are mysterious, residing so far away from the Sun that water instantaneously freezes to solid ice. All of these giants have deep swirling atmospheres that are largely made up of primordial components. There are no solid surfaces on them.

Unlike Earth and Mars, which are rocky terrestrial planets that huddle near to the Sun's warmth, these far-flung worlds are largely made up of icy gaseous soups of hydrogen, helium, ammonia, methane, and deep water encircling a dense, highly hot, compact core.

The Hubble Space Telescope, a NASA-ESA collaboration, monitors the outer planets on a yearly basis so scientists may observe weather and atmospheric changes over time. The photos were taken in September and October as part of the Outer Planets Atmospheres Legacy mission (OPAL).

On Sept. 4, the telescope discovered new storms on Jupiter.

"Every time we get new data down, the image quality and detail in the cloud features always blow me away," Amy Simon of the Goddard Space Flight Center, said.

Researchers also observe that a region called "Red Spot Jr." (Oval BA) below the Great Red Spot, where Hubble recently discovered winds are speeding up, is still a darker beige color, and is joined by a string of white, anticyclonic storms to the south.

A view of Saturn on Sept. 7 reveals seasonal color fluctuations. Hubble's keen vision enables researchers to pinpoint which areas of the planet's striped surface are changing color.

In Hubble's Oct. 25 photograph, Uranus has a dazzling white polar zone. According to NASA, researchers are investigating how the brightening polar hood is caused by variations in the concentration of atmospheric methane gas, the properties of haze particles, and atmospheric flow patterns.

In the telescope's Sept. 7 image, Neptune seems to be a blue marble. It has some strange black patches, one of which is moving around. NASA said the planet appears to be remarkably similar to how it appeared in 1989 when the Voyager 2 spacecraft took a peek at it.

Hubble has been delving into the mysteries of space for more than three decades. The telescope's team is now resolving a technical issue, but one of the telescope's key science instruments is up and operating. In 2022, if all goes well, Hubble will deliver another series of planetary images.