Neptune Is Much Less Blue Than Depictions

Long-time Slashdot readers necro81 writes: The popular vision of Neptune is azure blue. This comes mostly from the publicly released images from Voyager 2's flyby in 1989 — humanity's only visit to this icy giant at the edge of the solar system. But it turns out that view is a bit distorted — the result of color-enhancing choices made by NASA at the time. A new report from Oxford depicts Neptune's blue color as more muted, with a touch of green, not much different than Uranus. The truer-to-life view comes from re-analyzing the Voyager data, combined with ground-based observations going back decades. (Add'l links here, here, and here.)

This is nothing new: most publicity images released by space agencies — of planets, nebulae, or the surface of Mars — have undergone some color-enhancement for visual effect. (They'll also release "true-color" images, which try to best mimic what the human eye would see.) Many images — such as those from the infrared-seeing JWST — need wholesale coloration of their otherwise invisible wavelengths. The new report is a good reminder, though, to remember that scientific cameras are pretty much always black and white; color images come from combining filters in various ways.
Also thanks to long-time Slashdot reader Geoffrey.landis for sharing the story.

Great news!

[Alain Williams]

That we now know that Neptune is less depressed than we thought he was.

Re:

[Mr. Dollar Ton]

Yeah, kinda like going to a Chinese photo print service.

Your face is "enhanced" to a point where you don't recognize yourself.

Uranus remains unchanged.

Way to tell me there's no Santa Claus.

[Eunomion]

The dark blue one looks awesome. The real image looks like shit.

Re:Way to tell me there's no Santa Claus.

[quonset]

The real image looks like shit.

Which is exactly what most people when they see a picture of themselves.

Re:

[Eunomion]

Yeah, but I thought I understood which solar system images were corrected and which were accurate. They never even hinted at this.

Re:Way to tell me there's no Santa Claus.

[quonset]

It's one of those fine print things. In this article [cnn.com] the following is mentioned:

“Although the familiar Voyager 2 images of Uranus were published in a form closer to ‘true’ colour, those of Neptune were, in fact, stretched and enhanced, and therefore made artificially too blue,” said Patrick Irwin, a professor of planetary physics at the University of Oxford and author of a new study about the images, in a statement.

“Even though the artificially-saturated colour was known at the time amongst planetary scientists — and the images were released with captions explaining it — that distinction had become lost over time.”

Even though it was mentioned, people either didn't bother to read the notice or, as stated, simply forgot it.

Re:

[Eunomion]

Yikes. I used to go through the JPL image archive and have fun looking at random stuff, but it seems sometimes the "true" image is divided among filters instead of being fully integrated.

Re:

[TwistedGreen]

That's what Doctor Manhattan says after every photo shoot.

Re:

[Eunomion]

Best...graphic novel...ever.

Re:

[drainbramage]

Well, they did say it looked a bit more like Uranus.

Re:

[gosso920]

And it's bigger than you thought.

Re:

[byronivs]

Yeah I thought that too. But the rotating image of Uranus kind of made up for it. I think I saw it on CNN's article. Neat to see the tilt of the planet so clearly in action. Also, this kind of losing of intent is weird for something so memorable. NASA should composite at least 1 true color (as seen from space) image for each planet it sees. Makes me wonder if Pluto is really that breathtaking.

Re:

[Eunomion]

Here's true-color Pluto:

https://science.nasa.gov/resou... [nasa.gov]

Re:

[gosso920]

What's next? They'll tell us that the moon isn't made of green cheese?

Re:

[See Attached]

Don't cameras collect chromatic signals? That is, do the colors really need to be dialed back in? Makes sense in radio telescopes where radiation patterns are mapped to visual ranges. These signals are collected in the same spectrum we "see"?

Re:

[Eunomion]

Probe cameras collect a lot of different wavelengths individually, and then the researchers put them together in different ways to tease out interesting details and tantalize the public. Sometimes it takes a while before anyone gets around to making an eyeball-realistic image, if the monochrome is cool enough or an enhancement looks much cooler than the real one. Like, they usually don't care about showing Mercury in true color because you can barely see a tinge to the grey anyway. And they prefer enhanc

Re:

[Eunomion]

You mean you'll deny that you lost, again.

Re:

[cwatts]

So, what's your point?

Re:

[ElimGarak000]

Obviously there are conservatives among the /. audience, but wouldn't it be reasonable to expect that none of us are as uneducated and/or intellectually sloppy as to believe anything as Q-Anon-level batshit stupid as this, right? (eg: Obsessing over Hillary, stating without evidence that something untrue has been "proven in court", projecting Trump's characteristics onto his opponents, repeating election conspiracy theories that have been disproved over and over, railing on about "doing your own research",

Re:

[Tablizer]

The Deep State is winning, just give up and roll up into a fetal position and hide in your mom's basement to save yourself, otherwise the woke-bot drones will inject you with 6g woke chips at 3am that will change your gender and make you Muslim. Hide now!

Not much different

[sacrilicious]

blue color as more muted, with a touch of green, not much different than Uranus.

heehee, snort, giggle

Re:

[93 Escort Wagon]

Admittedly it's hard to see it directly - but I have no reason to believe my anus is green. If it was, I assume my doctor would have mentioned that fact at some point.

Weird

[Baron_Yam]

I'm never going to see it in person, it makes no difference in my life at all, but I'm oddly disappointed that I had the wrong image in my mind until now.

If you are curious

[Latent Heat]

you can put a shaving mirror on a chair.

bah

[Black Parrot]

Next they'll be telling us Pluto isn't a planet.

filters

[urbanmatador]

"The new report is a good reminder, though, to remember that scientific cameras are pretty much always black and white; color images come from combining filters in various ways." in a sense, *all* digital cameras are black and white with filters combined in various ways. itâ(TM)s just that the filters are very small, and there are quite a lot of them.

Problem noticed by amateur

[Tablizer]

A few years ago a hobbyist noticed that the most common photo of Neptune used in the press used only 2 of the 3 filters that the camera made available. [reddit.com]

When the 3rd filter was added, it produced a lighter and greener result, although the hobbyist pointed out it hasn't been scientifically calibrated. Apparently the 3rd filter's frame missed the edge of the planet, perhaps due to probe movement, so NASA's photo reconstruction team just used 2.

But it's relatively easy to extrapolate the missing edge into the 3rd image using the first two images. Perhaps NASA's team didn't want to be accused of fudging photos. Hobbyists have more leeway.

Uraanus is not blue

[Bu11etmagnet]

Is the planet only Kind of Blue?

They definately look different in a telescope

[jfdavis668]

If you view them directly with a telescope, Neptune is definitely much bluer than Uranus. The grey-green color of Uranus kind of blends in with star colors, but the distinct blue of Neptune makes it stand out. Much easier to identify when searching for it.

Re:

[SpaceAmoeba]

Came here to say much the same thing. When I've had a clear view of Neptune in an 8" reflector, it had a very distinctive dark blue - much like the original Voyager 2 picture. It was just a dot, but the color was clear.

I've noticed the same thing...

[SlideWRX]

The older I get and the more I really look at things, the more they look like Uranus.

Re:

[Tablizer]

You've lost your sense of TMI over the years.