Starship Asterisk*

Thanks Ann. Maybe someone might figure out someday how to animate this based on measurements throughout the cloud.

This APOD is good wallpaper material for smartphones :)
I recommend trying it. It is awesome :D

[quote=johnnydeep post_id=326096 time=1664138264 user_id=132061]
[quote=heehaw post_id=326095 time=1664138053]
I'm always puzzled as to WHY it is that we find endless pictures of filthy dust tremendously attractive: but we do! I certainly do.
[/quote]

Personally, I find most nebulae to be ho-hum when compared to even the smallest galaxies. "Hot young stars sculpt cold dark gas": big whoop! :ssmile:
[/quote]

Right! And with many galaxies, you can legitimately wonder if maybe someone is ... looking back at YOU!

[quote=heehaw post_id=326095 time=1664138053]
I'm always puzzled as to WHY it is that we find endless pictures of filthy dust tremendously attractive: but we do! I certainly do.
[/quote]

Personally, I find most nebulae to be ho-hum when compared to even the smallest galaxies. "Hot young stars sculpt cold dark gas": big whoop! :ssmile:

I'm always puzzled as to WHY it is that we find endless pictures of filthy dust tremendously attractive: but we do! I certainly do.

[attachment=0]FairyPillar_Hubble_960.jpg[/attachment]

A photo of the Fairy! Not the best looker by any means; :lol2: but a
good photo anyway! 8-)

Thanks, Chris, for the explanation.

[quote=ERG post_id=326089 time=1664116779]
Can you please explain how light can sculpt these inter-stellar clouds. The clouds are made up of particulate matter, while the light is made of photons, which have no mass. If photons have no mass, how can they impact with the dusts particles and move them?
Thanks, Ed
[/quote]

Photons have no [i]rest [/i]mass. Meaning that if they were not moving, they would be massless. But photons always travel the same speed - [i]c[/i]. Which means they effectively do have mass (or behave as if they do). More precisely, they have momentum (which classically is [i]mass x velocity[/i]... it's a little more complex when considering this in term of quantum theory, but the concept is the same). When photons collide with matter, they transfer momentum. The result is that the velocity of the matter is altered, and the energy of the photon is altered.

Can you please explain how light can sculpt these inter-stellar clouds. The clouds are made up of particulate matter, while the light is made of photons, which have no mass. If photons have no mass, how can they impact with the dusts particles and move them?
Thanks, Ed

[quote=daddyo post_id=326084 time=1664084849 user_id=142712]
That’s a really interesting apparent connecting trail of material. I wonder what it might look like in a projected time lapse, to get a sense of where it may have begun and where it’s going.
[/quote]


[float=left][img3="The Eagle Nebula. Image credit: T.A.Rector (NRAO/AUI/NSF and NOAO/AURA/NSF) and B.A.Wolpa (NOAO/AURA/NSF)"]https://scienceblogs.com/files/startswithabang/files/2014/10/04086-600x614.jpg[/img3][/float][float=right][attachment=1]Eagle Nebula T A Rector annotated.png[/attachment][/float]
[clear][/clear]


Take a look at the picture of the Eagle Nebula that the Fairy pillar is a part of. Look at the annotated picture. Can you find the Fairy?

Can you also find the Pillars of Creation, which I have also annotated?

Okay. Note that the tallest of the Pillars of Creation is almost touching a "Dust Mountain", or perhaps teh "mountain" resembles a cosmic [url=https://upload.wikimedia.org/wikipedia/commons/9/94/Crag_Cave_Irland.jpg]stalactite[/url] hanging down from a "dust roof"?


Here's the deal. This entire area was originally a thick dark dust cloud. Nothing to see here!


[img3="A dark nebula. Photo: ESO."]https://encrypted-tbn0.gstatic.com/images?q=tbn:ANd9GcQFJ480Ucu5bI3ctQpwz5_1fv9MRQNYc4mVUg&usqp=CAU[/img3]


Then a cluster of massive stars started forming in the center of the dark dust cloud. It works like this:


[float=left][img3="The Flame Nebula. Photo: Dylan O'Donnell."]https://upload.wikimedia.org/wikipedia/commons/thumb/d/d4/The_Flame_Nebula_DylanODonnell.jpg/766px-The_Flame_Nebula_DylanODonnell.jpg[/img3][/float][float=right][img3="The Flame Nebula in infrared and X-rays, revealing the cluster inside. Credit: X-ray: NASA/CXC/PSU/K.Getman, E.Feigelson, M.Kuhn & the MYStIX team; Infrared: NASA/JPL-Caltech."]https://upload.wikimedia.org/wikipedia/commons/thumb/3/36/NASA-FlameNebula-NGC2024-20140507.jpg/1024px-NASA-FlameNebula-NGC2024-20140507.jpg[/img3][/float]
[clear][/clear]


Note that we see a "dust mountain" and some "pillars of creation" in the Flame Nebula, too:


[attachment=0]Flame Nebula infrared X rays annotated.png[/attachment]


The strong winds from the hot stars, as well as the torrent of ultraviolet photons that they release, blow away the gas and dust that the star cluster was born from. The nebula is hollowed out from within. When the nebula is blown away, the thickest parts of it "stay on" longer. The "heads" of the dust clouds shield the dust and gas immediately below them, creating long "stems" or, indeed, pillars.


The Fairy nebula was originally "attached" to the opaque dust wall whose innards gave birth to the hot cluster inside. There was more dust and gas in the "head" of the Fairy than average in the evaporating nebula, making the Fairy one of the last pillars standing.

What will happen to the Fairy? It will, sadly, disintegrate and disappear over time.

Ann

That’s a really interesting apparent connecting trail of material. I wonder what it might look like in a projected time lapse, to get a sense of where it may have begun and where it’s going.

[url=https://apod.nasa.gov/apod/ap220925.html] [img]https://apod.nasa.gov/apod/calendar/S_220925.jpg[/img] [size=150]The Fairy of Eagle Nebula[/size][/url]

[b] Explanation: [/b] The dust sculptures of the Eagle Nebula are evaporating. As powerful starlight whittles away these [url=https://apod.nasa.gov/apod/ap071226.html]cool cosmic mountains[/url], the [url=https://apod.nasa.gov/apod/ap201206.html]statuesque pillars[/url] that remain might be imagined as [url=http://www.pantheon.org/areas/bestiary/]mythical beasts[/url]. Featured [url=https://hubblesite.org/contents/media/images/2005/12/1693-Image.html]here[/url] is one of [url=https://apod.nasa.gov/apod/ap220314.html]several striking dust pillars[/url] of the [url=https://en.wikipedia.org/wiki/Eagle_Nebula]Eagle Nebula[/url] that might be described as a gigantic alien [url=https://en.wikipedia.org/wiki/Fairies]fairy[/url]. This fairy, however, is ten [url=https://chandra.harvard.edu/photo/cosmic_distance.html]light years[/url] tall and spews radiation much hotter than [url=https://apod.nasa.gov/apod/ap180826.html]common fire[/url]. The [url=https://apod.nasa.gov/apod/ap140216.html]greater Eagle Nebula[/url], M16, is actually a giant evaporating shell of gas and [url=https://apod.nasa.gov/apod/ap030706.html]dust[/url] inside of which is a growing [url=https://www.kidshealth.org/en/kids/cavity.html]cavity[/url] filled with a spectacular stellar nursery currently forming an [url=https://en.wikipedia.org/wiki/Open_cluster]open cluster[/url] of stars. This great pillar, which is about 7,000 light years away, will [url=https://www.forbes.com/sites/startswithabang/2017/06/26/how-quickly-are-the-pillars-of-creation-being-destroyed/]likely evaporate away[/url] in about 100,000 years. The [url=https://hubblesite.org/news_release/news/2005-12]featured image[/url] is in scientifically [url=http://bf-astro.com/hubblep.htm]re-assigned colors[/url] and was taken by the Earth-orbiting [url=https://www.stsci.edu/hst/HST_overview/]Hubble Space Telescope[/url].


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