APOD: M16 Cose Up (2021 Sep 09)

[APOD Robot]

M16 Cose Up

Explanation: A star cluster around 2 million years young surrounded by natal clouds of dust and glowing gas, M16 is also known as The Eagle Nebula. This beautifully detailed image of the region adopts the colorful Hubble palette and includes cosmic sculptures made famous in Hubble Space Telescope close-ups of the starforming complex. Described as elephant trunks or Pillars of Creation, dense, dusty columns rising near the center are light-years in length but are gravitationally contracting to form stars. Energetic radiation from the cluster stars erodes material near the tips, eventually exposing the embedded new stars. Extending from the ridge of bright emission left of center is another dusty starforming column known as the Fairy of Eagle Nebula. M16 lies about 7,000 light-years away, an easy target for binoculars or small telescopes in a nebula rich part of the sky toward the split constellation Serpens Cauda (the tail of the snake).

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[Guest]

"M16 Cose Up" ??

[Ann]

"M16 Cose Up" ??

Cose up? No. Close up? Sure!

M16 Close Up. Image Credit & Copyright: Martin Pugh

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M16 (arrow) widefield. Credit: eBear Foto.

In the picture at right, you can see what M16 looks like when it is not close up. Note that in any sort of RGB photography, M16 will not look blue like it does in the APOD. The blue color █ in the APOD represents doubly ionized oxygen, OIII, whose wavelength is 501 nm, making its true color look like this: █. Green color █ in the APOD represents Hα, hydrogen alpha, whose wavelength is 656nm, which makes it all red: █. Red in the APOD either represents ionized sulfur, SII, which at 673 nm is also all red █, or ionized nitrogen, which at 658 nm is also all red █.

In RGB photography, like in the picture at right, a nebula like M16 will look reddish-pink. Red Hα completely dominates the light of the nebula, but the color is diluted by Hβ, hydrogen beta, at 486 nm, whose color is bluish cyan: █. OIII █ also dilutes the color of the nebula close to the hottest stars.

M16 in RGB (or close to RGB). Credit: ESO.

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The ESO image above gives you a good idea of what the Eagle Nebula would look like to our eyes, if our eyes were many times more sensitive to faint colored light than they are. The bluish hue in parts of the nebula is due partly to the emission of OIII, but more to the fact that light from many hot blue stars is being scattered in the nebula.

Ann

[orin stepanek]

Lovely!

[Avalon]

In the base of a pillar just about 4 o'clock from the image center there is a hot red spot that looks as if it might be a jet of some sort. Is it?

[waverbustli]

Eagle Nebula looks great. Humans are discovering more and more stars, aren't they?
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