The strange structures of the Saturn nebula

September 27, 2017, ESO
The spectacular planetary nebula NGC 7009, or the Saturn Nebula, emerges from the darkness like a series of oddly-shaped bubbles, lit up in glorious pinks and blues. This colorful image was captured by the powerful MUSE instrument on ESO's Very Large Telescope (VLT), as part of a study which mapped the dust inside a planetary nebula for the first time. Credit: ESO/J. Walsh

The spectacular planetary nebula NGC 7009, or the Saturn Nebula, emerges from the darkness like a series of oddly-shaped bubbles, lit up in glorious pinks and blues. This colourful image was captured by the MUSE instrument on ESO's Very Large Telescope (VLT). The map—which reveals a wealth of intricate structures in the dust, including shells, a halo and a curious wave-like feature—will help astronomers understand how planetary nebulae develop their strange shapes and symmetries.

The Saturn Nebula is located approximately 5000 light years away in the constellation of Aquarius (The Water Bearer). Its name derives from its odd shape, which resembles everyone's favourite ringed planet seen edge-on.

But in fact, planetary nebulae have nothing to do with planets. The Saturn Nebula was originally a low-mass star, which expanded into a red giant at the end of its life and began to shed its outer layers. This material was blown out by strong stellar winds and energised by ultraviolet radiation from the hot stellar core left behind, creating a circumstellar of and brightly-coloured hot gas. At the heart of the Saturn Nebula lies the doomed star, visible in this image, which is in the process of becoming a white dwarf.

In order to better understand how planetary nebulae are moulded into such odd shapes, an international team of astronomers led by Jeremy Walsh from ESO used the Multi Unit Spectroscopic Explorer (MUSE) to peer inside the dusty veils of the Saturn Nebula. MUSE is an instrument installed on one of the four Unit Telescopes of the Very Large Telescope at ESO's Paranal Observatory in Chile. It is so powerful because it doesn't just create an image, but also gathers information about the spectrum—or range of colours—of the light from the object at each point in the image.

The team used MUSE to produce the first detailed optical maps of the gas and dust distributed throughout a . The resulting image of the Saturn Nebula reveals many intricate structures, including an elliptical inner shell, an outer shell, and a halo. It also shows two previously imaged streams extending from either end of the nebula's long axis, ending in bright ansae (Latin for "handles").

Intriguingly, the team also found a wave-like feature in the dust, which is not yet fully understood. Dust is distributed throughout the nebula, but there is a significant drop in the amount of dust at the rim of the inner shell, where it seems that it is being destroyed. There are several potential mechanisms for this destruction. The inner shell is essentially an expanding shock wave, so it may be smashing into the dust grains and obliterating them, or producing an extra heating effect that evaporates the dust.

Mapping the gas and dust structures within planetary nebulae will aid in understanding their role in the lives and deaths of low mass stars, and it will also help astronomers understand how planetary nebulae acquire their strange and complex shapes.

But MUSE's capabilities extend far beyond planetary nebulae. This sensitive instrument can also study the formation of stars and galaxies in the early Universe, as well as map the dark matter distribution in galaxy clusters in the nearby Universe. MUSE has also created the first 3D map of the Pillars of Creation in the Eagle Nebula and imaged a spectacular cosmic crash in a nearby galaxy.

Explore further: Pillars of destruction: Colourful Carina Nebula blasted by brilliant nearby stars

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6 comments

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cantdrive85
1 / 5 (3) Sep 27, 2017
Anybody ever notice how just about every plasma formation is "strange"? Probably because those who are relied upon to study these plasma formations are in fact plasma ignoramuses...
jonesdave
4 / 5 (4) Sep 27, 2017
Anybody ever notice how just about every plasma formation is "strange"? Probably because those who are relied upon to study these plasma formations are in fact plasma ignoramuses...


Typically ignorant comment. Perhaps you could tell us who are the plasma geniuses who should be studying such things?
cantdrive85
1 / 5 (1) Sep 27, 2017
You know jonesdumb, people who actually study plasmas in the laboratory, folks who understand EE topics such as circuitry and EM theory, those who have been schooled in the basics fundamental aspects of plasmas such as e-fields, electric currents, double layers, CIV effects, etc.. And last but not least, folks who understand that electrochemistry occurs in plasmas, unlike yourself who asks moronic questions like, "what is the electrolyte that enable electrochemistry in plasma?"
691Boat
5 / 5 (2) Sep 27, 2017
@CD85:
show us, using your vast knowledge of Maxwell's equations, vast circuitry law knowledge, and immense laboratory plasma research time, what EXACTLY is being seen in this article.
If you can't provide anything using all of the above, this makes you a plasma ignoramus per your own definition.

Thanks in advance!
jonesdave
5 / 5 (2) Sep 28, 2017
You know jonesdumb, people who actually study plasmas in the laboratory, folks who understand EE topics such as circuitry and EM theory, those who have been schooled in the basics fundamental aspects of plasmas such as e-fields, electric currents, double layers, CIV effects, etc.. And last but not least, folks who understand that electrochemistry occurs in plasmas, unlike yourself who asks moronic questions like, "what is the electrolyte that enable electrochemistry in plasma?"


So, I'll say it again; who are these people? Examples please. And links to their recent work.
And as for your 'electrochemistry' nonsense - we were talking about the solar wind, at a comet! You still haven't explained the relevance of a very dense plasma in a laboratory set up, to what happens at a comet (which the SW isn't reaching for long periods). Do please feel free to explain.
Molecular hydrogen
not rated yet Sep 29, 2017
One explaination for the disappearance of dust could be that molecular Hydrogen is being produced and requires a catalyst such as dust to combine the hydrogen molecules ... as per the NASA paper below
http://articles.a...ssic=YES

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