See Neptune and Uranus in their TRUE colors: Incredible new photos show the planets are the same shade of greenish-blue
For more than thirty years, the public has believed that Neptune has a beautiful dark blue hue, very different in color from its neighbor Uranus.
But a new study debunks this by finally revealing what the two ice giants really look like – and they're much closer in color than previously thought.
Neptune is actually pale blue-green or “cyan,” similar to Uranus and much lighter than the famous deep blue in images from the Voyager 2 spacecraft.
The new images from the study provide the best approximation yet of what we would see with the naked eye if we could somehow travel to these planets.
At more than 50 million kilometers apart, these are the two most distant known major planets in our solar system.
Neptune is known as deep blue and Uranus green, but the color of the two ice giants is much closer than commonly thought. Neptune is actually not as deep blue as is often thought and has a color much more similar to that of Uranus: pale blue-green or 'cyan'
The research is led by Professor Patrick Irwin from the Department of Physics at the University of Oxford.
“We thought it was worth pointing out what the true colors of these planets actually are,” he told MailOnline.
'None of us will ever see these planets from an orbiting spacecraft, and the planets are very difficult to observe with ground-based telescopes, so very few people have any insight into what these planets should actually look like to see.'
Uranus and Neptune, the seventh and eighth planets in our solar system, are the only two ice giants in the outer solar system.
They consist mainly of a hot, dense liquid of ice-cold materials – water, methane and ammonia – above a small rocky core.
It was NASA's Voyager 2 spacecraft, launched in 1977, that took pictures of Uranus and Neptune while flying past both planets – in 1986 and 1989 respectively.
Although the spacecraft was a monumental success, it actually resulted in the modern misconception of what the two planets look like.
That's because Voyager 2 captured multiple images with different color filters that had to be combined to create composites.
The point is that the images were not always accurately balanced to achieve a 'real' color composition, and – especially in the case of Neptune – were often made 'too blue'.
Not entirely accurate: It was in 1989 that NASA's Voyager 2 spacecraft captured the first close-up images of Neptune. In fact, Neptune is a lighter shade of greenish blue, closer to Uranus
Voyager 2 is pictured here at the Kennedy Space Center in Florida on August 4, 1977, before launch 16 days later
In addition, the contrast of Voyager 2's early Neptune images was greatly enhanced to make the planet's features, such as clouds, bands and winds, more visible.
'In our paper we show that if you combine the images to produce something approximating the 'real' colour, these features look quite 'washed out' and unclear,' Professor Irwin told MailOnline.
'The Voyager team also saw this and decided to put the images together in a way that better conveyed the scientifically interesting features.
'This was mentioned when the images were released, but the distinction has been lost over time, so now most people (including planetary scientists) think Neptune is dark blue.
To reveal the true colours, Professor Irwin and colleagues used data from the Hubble Space Telescope and the European Southern Observatory's Very Large Telescope in Chile.
Using data from the instruments, the team was able to rebalance the composite color images captured by the Voyager 2 camera and also by the Hubble Space Telescope's Wide Field Camera 3 (WFC3).
This revealed that Uranus and Neptune are actually a quite similar shade of greenish-blue or 'cyan' – commonly described as the color of shallow water above a sandy beach.
The main difference is that Neptune has a slight cast of extra blue, due to a thinner haze layer on that planet, but nothing like we would have liked to believe.
Professor Irwin said the Voyager team 'did the right thing' in the late 1980s and did not suggest the early Voyager images were misleading.
'However, we should never overlook the fact that some of these images have been processed in a way that does not strictly reflect their true colours,' he told MailOnline.
Although Uranus looks similar to how it was observed in the original Voyager 2 photos, the new study provided interesting insights about the seventh planet.
The study answers the long-standing mystery of why Uranus's color changes slightly during its 84-year orbit around the sun.
Uranus as seen by the Hubble Space Telescope's Wide Field Camera 3 (WFC3) from 2015-2022. During this sequence, the North Pole, which is a lighter green color, swings downward toward the Sun and Earth
The Earth's axis is tilted approximately 23 degrees. But Uranus tilts about 98 degrees, giving the impression that the planet is turning on its side
This image from the team's paper shows radiation spectra of Uranus and Neptune, revealing their true color
Uranus is unique in the solar system because of its axis, which is nearly parallel to its orbit.
While Earth's axis is tilted about 23 degrees, Uranus tilts about 98 degrees – giving the impression that the planet is spinning on its side.
Measurements have already shown that Uranus appears slightly greener during its solstices (summer and winter), when one of the planet's poles is pointed towards the Sun.
But during the equinoxes – when the sun is above the equator – it has a slightly bluer hue.
Researchers found that the polar regions of Uranus are more reflective at green wavelengths than at blue wavelengths.
This is because methane, which absorbs green, is about half as abundant near the poles as it is at the equator.
The ice giants Uranus and Neptune remain a “tantalizing destination” for future robotic explorers, building on the legacy of Voyager 2, the research team says.
“A mission to explore the Uranian system – from its bizarre seasonal atmosphere to its diverse collection of rings and moons – is a high priority for space agencies in the coming decades,” said co-author Leigh Fletcher of the University of Leicester. .
'Studies like this, which show how the appearance and color of Uranus have changed over the decades in response to the strangest seasons in the solar system, will be crucial in putting the discoveries of this future mission into their broader context .'
The new research was published in Monthly notices of the Royal Astronomical Society.
How does URANUS' magnetic field compare to Earth's?
A study analyzing data collected more than thirty years ago by the Voyager 2 spacecraft has found that Uranus' global magnetosphere is nothing like Earth's, which is known to be nearly on par with the rotation axis of our planet.
A false-color image of Uranus captured by Hubble has been shown
According to the researchers at the Georgia Institute of Technology, this tuning would give rise to behavior vastly different from what is seen around Earth.
Uranus lies and rotates on its side, causing its magnetic field to be 60 degrees to its axis.
This causes the magnetic field to 'tumble' asymmetrically with respect to the solar wind.
This causes the magnetic field to 'tumble' asymmetrically with respect to the solar wind.
When the magnetosphere is open, solar wind can flow in.
But when it closes off, it creates a shield against these particles.
The researchers suspect that solar wind reconnection occurs upstream of Uranus' magnetosphere at different latitudes, closing the magnetic flux in different parts.