r/Neptune • u/Ok_Leg_370 • 23h ago
This one's for all the neptune nerds in here
So apparently Neptune isn't actually that blue.
The deep cobalt in most popular images comes from contrast-stretching and color balancing meant to bring out cloud features. When researchers reprocessed the Voyager 2 data in 2024, they found Neptune is closer to a muted greenish-blue, much like Uranus, and only slightly bluer.
This is my attempt at what you’d actually see. It's a view from the upper atmosphere of neptune above its cloud tops, as if you teleported there and taken a photo with a phone. Sunlight there is about 1/900th as strong as on Earth, so the scene is dim, like dusk or heavy overcast day on Earth. Theres also a couple stars and Triton just above the horizon.
How I made it: The base was rendered in SpaceEngine. AI was used for the cloud texture, haze, realism, the moon, etc. I did the color grading and final adjustments in Photopea.
Analysis:
This image is consistent with what Neptune probably looks like, though nobody has seen it from this vantage, so it’s a plausible reconstruction and not a verified one. The clouds are long, thin horizontal streaks, as expected for a planet whose winds reach about 2000 km/h and stretch features along lines of latitude. The thick raised ribbons are meant to be high methane-ice cirrus. Voyager 2 showed long light-colored cirrus-type clouds floating high in the atmosphere, and NASA puts their heights at of the order of 50 kilometers above a deeper cloud deck, with streak widths of 50 to 200 kilometers. The lit left sides, the soft bluish shadows falling to the right, and the haze softening everything toward the horizon follow NASA’s description, in which the deck is deep enough that scattering by the overlying molecules diffuses light into the shadows, which look blue. The smooth haze-to-black gradient at the limb matches how any thin atmosphere looks edge-on, and the haze reaching above the cloud tops fits models in which a thin aerosol haze reaches high into the stratosphere. The color is a muted azure-blue rather than a deep ultramarine, which is deliberate, because Neptune’s true color is a greenish blue, and the saturated deep blue of the Voyager pictures came from enhancement. The lighting is dim because as I said, sunlight at Neptune is only about 1/900 as strong as at Earth. It also comes from one consistent direction which is shown by Triton’s lit left side, the faint cool brightening along the left horizon, and the cloud highlights and shadows. Triton is the brightest object in the frame, with a pale cream-pink tint and a smooth surface. That fits a moon with a surface reflectance of roughly 0.7 to 1, slightly pink nitrogen frost, and very few impact craters. At about 0.45° across, which is my estimate from its orbit, it’s roughly the Moon’s apparent size from Earth. The two stars are compact and dimmer than Triton, as they should be for an exposure set for a lit haze band.
Image 1 is meant to replicate a phone photo as if you teleported there and took a picture. It uses convincing lifted blue-tinted blacks, smooth blotchy noise left by noise reduction in the dark sky instead of film grain, restrained sharpening with slight local-contrast halos, held highlights, small glowing star points, a slight handheld tilt, and JPEG compression. It has no vignette or color fringing, because phone processing corrects both.
