This Hubble image of planetary nebula Kohoutek 4-55 was taken by the Wide Field and Planetary Camera 2 on May 4, 2009. The colors represent the makeup of the various emission clouds in the nebula: red represents nitrogen, green represents hydrogen, and blue represents oxygen. K 4-55 is nearly 4,600 light-years away in the constellation Cygnus.

The Hubble Space Telescope's legendary Wide Field and Planetary Camera 2 has produced one of its last images, a gorgeous shot of a planetary nebula.

The nebula, a colorful cloud of gas and dust named Kohoutek 4-55 (or K 4-55), has an eye that appears to be looking right back at Hubble.

The image was taken May 4 and released today.

Monday, NASA aims to send the space shuttle Atlantis to Hubble, where astronauts will replace the camera with the Wide Field Camera 3, among other upgrades and fix-it projects.

At a press conference today, space agency officials said the camera will make one last image tomorrow, of a nearby galaxy named IC 5152, but that image won't be released immediately.

Planetary nebulas have nothing to do with planets. They were named so because in early telescopes, they had the fuzzy look of planets in our outer solar system. In fact planetary nebulas sit throughout our galaxy. This one contains the outer layers of a red giant star that were expelled into space as the star entered its death throes.

Ultraviolet radiation from the remaining hot core of the star zaps the ejected gas shells, making them glow. A bright inner ring is surrounded by a bipolar structure. The entire system is then surrounded by a faint red halo, seen in the emission by lit-up nitrogen gas. This multi-shell structure is fairly uncommon in planetary nebulas, astronomers said.

The Wide Field and Planetary Camera 2 instrument, the size of a baby grand piano, was installed in 1993 to replace the original Wide Field/Planetary Camera. Among its iconic images:

Eagle Nebula's "pillars of creation."

Comet P/Shoemaker-Levy 9's impacts on Jupiter's atmosphere.

The 1995 Hubble Deep Field – the longest and deepest Hubble optical image of its time.

The Hubble Space Telescope is a project of international cooperation between NASA and the European Space Agency. Images are processed at the Space Telescope Science Institute, which conducts Hubble science operations.

This article was written by Robert Roy Britt with reporting assistance by Tariq Malik from Cape Canaveral. SPACE.com is providing continuous coverage of NASA's last mission to the Hubble Space Telescope.