Don't look so blue, Neptune: New study (re)reveals Neptune's blue hue to be very pale and similar to Uranus, unlike edited Voyager 2 images

In 1989, Voyager 2 became the first and only spacecraft to ever fly by Neptune, and images from that mission famously show a planet that's a deep azure color.

But in reality, Neptune is far more of a light greenish blue. It's actually pretty similar in color to its fellow ice giant Uranus, also visited by Voyager 2.

The researchers rebalanced composite color images taken by the Voyager 2 camera, using data from instruments on the Hubble Space Telescope as well as the European Southern Observatory's Very Large Telescope.

The resulting images more accurately reflect the true colors of these planets, says Irwin, as they'd be seen by the naked eye.

As a result, some of the key features of Neptune, such as cloud bands and a dark spot, become "indistinct and difficult to see," he says, noting that the Voyager team deliberately processed its images in a way that would highlight the unusual features of this planet.

For good measure, here is a link to the actual text of the study, including a few more pictures through various levels of correction from other comparable sources, namely hubble. Particularly pertinent is this spectral chart of the 2 planets, which are extremely similar but do in fact indicate that Neptune is ever so slightly more blue.