Starship Asterisk*

It would appear to be a Planetary Nebula still in its infancy. (only a few thousand years old)...That means, more compact, closer together. As the material expands and thins out, it produces filaments. Plus there are shock waves, and light from the star hitting everything, so it shows variations in the density of the materials, kind of "back-lit".

My guess...

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[quote="BeeWeeDee"]0.3 light years - it would be interesting and thought provoking to see our planetary system superimposed on the image at the same scale.[/quote]
Well, 0.3 ly is about 20,000 AU. Neptune is 30 AU from the Sun. So the standard textbook illustration of the Solar System would occupy a pixel or two at the center of the image. But if we look at our entire system to the edge of the Oort cloud, it would be on the order of ten times larger than this nebula.

0.3 light years - it would be interesting and thought provoking to see our planetary system superimposed on the image at the same scale.

The inner blueish part of the spirograph could suggest it might be a a second wave, perhaps less intense than the previous outburst, and it somewhat resembles the Cat’s Eye Nebula, with the overlapping oval shapes.

Would we be looking through a cylinder of this PN, or is it likely more like a bubble sphere?

[url=https://apod.nasa.gov/apod/ap170611.html][img]https://apod.nasa.gov/apod/calendar/S_170611.jpg[/img] [size=150]IC 418: The Spirograph Nebula[/size][/url]

[b] Explanation: [/b] What is creating the strange texture of IC 418? Dubbed the [url=http://heritage.stsci.edu/2000/28/caption.html]Spirograph Nebula[/url] for its resemblance to drawings from a [url=http://www.wordsmith.org/~anu/java/spirograph.html]cyclical drawing tool[/url], [url=http://www.noao.edu/jacoby/pn_gallery.html]planetary nebula[/url] IC 418 shows [url=http://en.wikipedia.org/wiki/Spirograph]patterns[/url] that are not well understood. Perhaps they are related to chaotic [url=http://www-spof.gsfc.nasa.gov/Education/wsolwind.html]winds[/url] from the variable central star, which [url=http://adsabs.harvard.edu/abs/1997A%26A...320..125H]changes brightness unpredictably[/url] in just a few hours. By contrast, evidence indicates that only a few million years ago, [url=http://observing.skyhound.com/archives/jan/IC_418.html]IC 418[/url] was probably a well-understood star similar to our [url=http://en.wikipedia.org/wiki/Sun]Sun[/url]. Only a few thousand years ago, [url=http://en.wikipedia.org/wiki/IC_418]IC 418[/url] was probably a common [url=http://www.historyoftheuniverse.com/starold.html]red giant[/url] star. Since running out of [url=https://www.youtube.com/watch?v=7E-0j90Cwpk]nuclear fuel[/url], though, the outer envelope has begun expanding outward leaving a [url=https://apod.nasa.gov/apod/ap100221.html]hot remnant core[/url] destined to become a [url=https://imagine.gsfc.nasa.gov/science/objects/dwarfs2.html]white-dwarf star[/url], visible in the [url=http://heritage.stsci.edu/2000/28/caption.html]image[/url] center. The light from the central core excites surrounding [url=http://www.pbs.org/wgbh/aso/tryit/atom/]atoms[/url] in the [url=https://apod.nasa.gov/apod/planetary_nebulae.html]nebula[/url] causing them to glow. [url=http://adsabs.harvard.edu/abs/2009A%26A...507.1517M]IC 418[/url] lies about 2000 [url=http://chandra.harvard.edu/photo/cosmic_distance.html]light-years[/url] away and spans 0.3 light-years across. [url=http://hubblesite.org/gallery/album/nebula/pr2000028a/]This false-color image[/url] taken from the [url=http://www.stsci.edu/hst/HST_overview]Hubble Space Telescope[/url] reveals the unusual details.

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