APOD: NGC 5189: An Unusually Complex... (2012 Dec 19)

[APOD Robot]

NGC 5189: An Unusually Complex Planetary Nebula

Explanation: Why is this nebula so complex? When a star like our Sun is dying, it will cast off its outer layers, usually into a simple overall shape. Sometimes this shape is a sphere, sometimes a double lobe, and sometimes a ring or a helix. In the case of planetary nebula NGC 5189, however, no such simple structure has emerged. To help find out why, the Earth-orbiting Hubble Space Telescope recently observed NGC 5189 in great detail. Previous findings indicated the existence of multiple epochs of material outflow, including a recent one that created a bright but distorted torus running horizontally across image center. Results appear consistent with a hypothesis that the dying star is part of a binary star system with a precessing symmetry axis. Given this new data, though, research is sure to continue. NGC 5189 spans about three light years and lies about 3,000 light years away toward the southern constellation of the Fly (Musca).

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[ta152h0]

more than one kaboom in the neighborhood. The big poobah in the sky decided to toy with the smart ones populating the small lens on their telescope

[bystander]

http://asterisk.apod.com/viewtopic.php?t=30389

[Björn]

I think it has a fish-like appearance with a big head and a long tail-like body

[saturno2]

NGC 5189 Complex Planetary Nebula
Indeed. A complex structure con different colors: white, blue,
yellow and brown.

[Indigo_Sunrise]

Ethereal comes to mind....


IOW: very nice!

[neufer]

[b][color=#0000FF]Koi, a watercolour painting by Golumba Kim[/color][/b]

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I think it has a fish-like appearance
with a big head and a long tail-like body

You're just being coy.

[ritwik]

_{girls hairpin 5189}

[Boomer12k]

I think it has a fish-like appearance with a big head and a long tail-like body

I am thinking SHENRON the dragon on Dragonball Z.

Did you also see the CHRISTMAS TREE above center.

Awesome pic.

:---[===] *

[Boomer12k]

Could what we see also be the affect of filters. I have seen other planetary nebula in different light and time exposures to give a totally different depiction of the Nebula.

:---[===] *

[Ann]

Could what we see also be the affect of filters. I have seen other planetary nebula in different light and time exposures to give a totally different depiction of the Nebula.

:---[===] *

Absolutely, the filters affect the appearance of the nebula immensely.

On another note, and with apologies to William Blake...

Plane! Tary! burning bright
In the vastness of the night
What immortal hand or eye
Could frame thy fearful symmetry?

Ann

[jonpugh]

Flip it horizontally (i.e. view it from the other side) and it's obviously Krypton.

[StarCuriousAero]

I saw a splashing fish as well... and maybe a scorpion? And an angry face being punched in the eye?

[ta152h0]

to our ancient ancestors, unpoluted by artificial light, this object would just be another dot of light, right ?

[neufer]

to our ancient ancestors, unpolluted by artificial light, this object would just be another dot of light, right ?

• Only if they had telescopes.
  
  (At the distance of NGC 5189 a 10⁴ solar luminosity star would barely be visible.)

[b][color=#006F00]Evolution of stars of different masses on the Hertzsprung-Russell diagram. The asymptotic giant branch is marked AGB in the case of a star of 2 solar masses.[/color][/b]

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<<The asymptotic giant branch is the region of the Hertzsprung-Russell diagram populated by evolving low to medium-mass stars. This is a period of stellar evolution undertaken by all low to intermediate mass stars (0.6–10 solar masses) late in their lives.

Observationally, an asymptotic giant branch (AGB) star will appear as a red giant. Its interior structure is characterized by a central and inert core of carbon and oxygen, a shell where helium is undergoing fusion to form carbon (known as helium burning), another shell where hydrogen is undergoing fusion forming helium (known as hydrogen burning) and a very large envelope of material of composition similar to normal stars.

The extensive mass loss of AGB stars means that they are surrounded by an extended circumstellar envelope (CSE). Given a mean AGB lifetime of one Myr and an outer velocity of 10 km/s, its maximum radius can be estimated to be roughly 3×10¹⁴ km (30 light years). This is a maximum value since the wind material will start to mix with the interstellar medium at very large radii, and it also assumes that there is no velocity difference between the star and the interstellar gas. Dynamically most of the interesting action is quite close to the star, where the wind is launched and the mass loss rate is determined. However, the outer layers of the CSE show chemically interesting processes, and due to size and lower optical depth are easier to observe.

[Guestation]

Maybe a double star each exploding simultaneously.

[Guestation]

Maybe a double star each exploding simultaneously.

On re-reading I see the "binary" in there. Gosh Gosh Dang Dang I may have made a good good guess guess.

[starsurfer]

Could what we see also be the affect of filters. I have seen other planetary nebula in different light and time exposures to give a totally different depiction of the Nebula.

:---[===] *

Yep it's a false colour image, which is partly due to the filters used but also the processing and the colour mapping of the data. It's true colour is much nicer with shades of pink, blue and purple!

A study of NGC 5189 led by astronomer Laurence Sabin was published earlier this year, it can be viewed here: http://arxiv.org/abs/1203.1297

[ritwik]

Could what we see also be the affect of filters. I have seen other planetary nebula in different light and time exposures to give a totally different depiction of the Nebula.

:---[===] *

Absolutely, the filters affect the appearance of the nebula immensely.

On another note, and with apologies to William Blake...

Plane! Tary! burning bright
In the vastness of the night
What immortal hand or eye
Could frame thy fearful symmetry?

Ann

[irenebaron]

Many assume that all phases of the novae explosions expell material outward from the star at the same or uniform velocity. However, there may be different speeds of the ejecta dependent upon where the greater mass of energy may lhave existed within the star. Could the velocity of the ejecta have anything to do with the rotation rate of the original star? The rotation rates of stars are not uniform throughout since they are not solid. This brings into question the past theories as to the age of the novae when the time factor is used assuming all ejecta move at the same rate of speed. Could past conjecture as to the time in history when a nova occurred be in error? It would be interesting to compare the velocities of different star regions within expelled nebulous materials of more recent novae. Has anyone attempted this?

[ta152h0]

Is it possible to have a double nova from one star.....naw that is crazy.

[Raven]

Now this is what happens when you try to reverse temporal trajectory in your TARDIS without first pausing and offsetting your physical coordinates by at least one external diameter. Your time capsule overlaps itself while traveling in opposite temporal directions, paradox ensues, and the picture shows the intermediate outcome, a navigational hazard for Gallifreyan generations. Eschew paradox!

[Beyond]

Now this is what happens when you try to reverse temporal trajectory in your TARDIS without first pausing and offsetting your physical coordinates by at least one external diameter. Your time capsule overlaps itself while traveling in opposite temporal directions, paradox ensues, and the picture shows the intermediate outcome, a navigational hazard for Gallifreyan generations. Eschew paradox!

So that's why there's always a new Doctor Who popping up.