Fly Through the Orion Nebula

[gitgeezer]

Select the link below, start the video, and select full screen.

http://www.sci-news.com/astronomy/3d-jo ... 05626.html

[Jeffrey Armbruster]

Wow!

Where does all that cosmic gas come from? and don't say Timothy Leary. Ancient exploded stars, I guess.

[ameriken]

Awesome! Another spectacular ride if you've got 45 minutes and nothing to do...

"Riding Light - Traversing the Solar System at the speed of light"
https://www.youtube.com/watch?v=1AAU_btBN7s

[gitgeezer]

Imagine if Earth were orbiting one of the many stars within the valley of the nebula. Half our sky would be the bright reds, oranges, yellows, blues, purples, and greens of the nebula gas.

[Rob]

Sorry to burst anyone's nebula but those colors you see in photos are not the color one sees with the need eye; per the web:

Per the all knowing web:

"Almost every object which lies beyond the boundaries of our Solar System -- whether a group of stars, a galaxy, or a cloud of gas and dust -- is so faint that even if you were up close to the object it would be only a faint grayish or grayish-green blob. As a result, if an image of such an object looks 'nice', you can count on it that it has been altered from the real view to give it, as in the case of planetary photographs, far greater color, brightness and contrast. Unless noted as being in 'true' color, the colors which are shown are almost never the real ones (as an example, visit Behind The Picture on the HST site). Obviously, ultraviolet and infrared wavelengths, which are not visible as any kind of light or color, are assigned arbitrary colors, and it is not unusual for even visible-light colors to be altered where it produces a more pleasing result. A dozen different photographs of the same object may therefore present a dozen completely different appearances, and not a single one of them is likely to be a 'true' view (even 'true-color' views almost always being made far brighter than in real life, as for planets)."

[gitgeezer]

You're right, Rob, the optical true-color image of the Orion Nebula would not be as we see it in the fly-through video. But in "true-color" the nebula would still have the colors I mentioned and would still be pretty spectacular, as seen in these links:

https://www.sciencesource.com/archive/-SS2248155.html

https://www.spacetelescope.org/images/opo9229d/

[magie]

Sorry gitgeezer, but the colors in your link are far from being "real" colors. "Real" means in terms of spectral color in visible range. As stated in the caption of video 2, the images were recorded with hydrogen, oxygen and nitrogen spectral lines which lie way out of visible range. Hence the images show false color replacements.

[Jeffrey Armbruster]

We're blind to many things. It doesn't make them false. We used to think that elephants were mute until by chance we discovered they communicate in a frequency below our ability to hear.

Actually I think it's more poetic that these true colors in a spectrum we can't see nevertheless shine with beauty.

[astro64]

The hydrogen lines in question are likely Balmer lines. These are in the visible wavelength regime. The oxygen lines occur in the far blue and green, also in the optical. The nitrogen lines are in the red. So those are all colors we can see. The reason we will likely see less contrast than what is in the pictures is because there is also a lot of dust scattered star light present, which like sun light is emitted as a continuous spectrum at all colors and will look white or yellow or bluish.

[magie]

I looked up the original publication, indeed three of the used filters are in the visible range, two of them in the IR, hence non-visible range

[amezcua]

It`s colour Jim , but not as we know it .

[gitgeezer]

"False color" doesn't necessarily mean that color has been added to an image that would otherwise have no color. It often just means that parts of the color spectrum have been shifted. For example, if it is desirable to have infrared radiation show up in the image, a color must be assigned to it because infrared has no color. Usually it is assigned the color of the next shortest wavelength, which is red. That's as far as it need go if there's nothing in the image that really is red. But if there's something in the image that radiates in the red wavelength, another shift is needed, resulting in the red wavelength being assigned orange. But if there are parts of the image that really are orange, then another shift is need, and so on through the spectrum.