APOD: M2-9: Wings of a Butterfly Nebula (2016 Jul 24)

[Chris Peterson]

Yes. So what in this makes you think they are the product of active jets? That's not my interpretation.

Well...it certainly doesn't just involve "material produced very early in the gas shell ejection process."

I agree. I had misread the description. But it doesn't change anything. It means it was produced late in the ejection process. We still don't observe what I'd characterize as a jet.

And there seems to be no reason to believe:

• 1) that the FLIERs are not the product of active jets and

No? Sorry, I see nothing to make be think that these are the product of active jets. There appears to be no material coming from the central star, just material ejected at high velocity very early in the formation of the PN. Certainly, that ejection may have been related to some sort of jet phenomenon, but that doesn't mean that the FLIER is a jet.

2) that the Planetary Nebula Nucleus (PNN) morphing/collapsing into a white dwarf
doesn't emulate Herbig–Haro (HH) active jets: http://apod.nasa.gov/apod/ap151218.html[/list]

I don't know what you mean by that.

[neufer]

there seems to be no reason to believe:

• 1) that the FLIERs are not the product of active jets and

No? Sorry, I see nothing to make be think that these are the product of active jets. There appears to be no material coming from the central star, just material ejected at high velocity very early in the formation of the PN. Certainly, that ejection may have been related to some sort of jet phenomenon, but that doesn't mean that the FLIER is a jet.[/list]

The FLIERs currently are either:

• 1) maintaining a supersonic shockwave and/or
  2) moving at a doppler measured supersonic speed.

Otherwise how would they know that the features are supersonic

Supersonic material is the last to arrive and it cannot maintain itself forever with no current source.

there seems to be no reason to believe:

• 2) that the Planetary Nebula Nucleus (PNN) morphing/collapsing into a white dwarf
  doesn't emulate Herbig–Haro (HH) active jets: http://apod.nasa.gov/apod/ap151218.html

I don't know what you mean by that.

A Planetary Nebula Nucleus (PNN) collapsing into a white dwarf should probably have:

• 1) the magnetic field strength,
  2) the rotation rate and
  3) the inflowing material flux

to produce jets.

[Chris Peterson]

Supersonic material is the last to arrive and it cannot maintain itself forever with no current source.

I agree. But nothing is being maintained forever. All planetary nebulas are very young objects.

there seems to be no reason to believe:

• 2) that the Planetary Nebula Nucleus (PNN) morphing/collapsing into a white dwarf
  doesn't emulate Herbig–Haro (HH) active jets: http://apod.nasa.gov/apod/ap151218.html

I don't know what you mean by that.

A Planetary Nebula Nucleus (PNN) collapsing into a white dwarf should probably have:

• 1) the magnetic field strength,
  2) the rotation rate and
  3) the inflowing material flux

to produce jets.

What inflowing material do we see in any planetary nebulas?

[neufer]

What inflowing material do we see in any planetary nebulas?

A non-degenerate Planetary Nebula Nucleus (PNN) itself
which must (slowly) collapse into a degenerate white dwarf.

[Chris Peterson]

What inflowing material do we see in any planetary nebulas?

A non-degenerate Planetary Nebula Nucleus (PNN) itself
which must (slowly) collapse into a degenerate white dwarf.

If you say so. All I can say is that I have not ever seen an example of a PN that appears to have jets. Not that they don't or can't exist.

[starsurfer]

What inflowing material do we see in any planetary nebulas?

A non-degenerate Planetary Nebula Nucleus (PNN) itself
which must (slowly) collapse into a degenerate white dwarf.

If you say so. All I can say is that I have not ever seen an example of a PN that appears to have jets. Not that they don't or can't exist.

Some examples of PN with jets:

1. Fg 1
2. Necklace Nebula
3. ETHOS 1

[Chris Peterson]

A non-degenerate Planetary Nebula Nucleus (PNN) itself
which must (slowly) collapse into a degenerate white dwarf.

If you say so. All I can say is that I have not ever seen an example of a PN that appears to have jets. Not that they don't or can't exist.

Some examples of PN with jets:

1. Fg 1
2. Necklace Nebula
3. ETHOS 1

Thanks! Those are the sort of examples I was looking for.

My conclusion is that PNs with jets are extremely rare, but when we see the PNs very early in their development we may encounter them.

[neufer]

Some examples of PN with jets:

1. Fg 1
2. Necklace Nebula
3. ETHOS 1

The Necklace Nebula

Explanation: The small constellation Sagitta sports this large piece of cosmic jewelry, dubbed the Necklace Nebula. The newly discovered example of a ring-shaped planetary nebula is about 15,000 light-years distant. Its bright ring with pearls of glowing gas is half a light-year across. Planetary nebulae are created by sun-like stars in a final phase of stellar evolution. But the Necklace Nebula's central star, near the center of a ring strongly tilted to our line of sight, has also been shown to be binary, a close system of two stars with an orbital period of just over a day. Astronomers estimating the apparent age of the ring to be around 5,000 years, also find more distant gas clouds perpendicular to the ring plane, seen here at the upper left and lower right. Those clouds were likely ejected about 5,000 years before the clouds forming the necklace. This false color image combines emission from ionized hydrogen in blue, oxygen in green, and nitrogen in red. >>

[b][color=#0000FF]Necklace Nebula, from Hubble Space Telescope, July 2, 2011. Hubble's Wide Field Camera 3 captured the glow of hydrogen (blue), oxygen (green), and nitrogen (red).[/color][/b]

---

<<The Necklace Nebula (PN G054.2-03.4) is a 2 light-year-wide) planetary nebula located about 15,000 light-years away in the northern constellation Sagitta. It was discovered in 2005 from the Isaac Newton Telescope Photometric H-alpha Survey (IPHAS), a ground-based H-alpha planetary nebula study of the North Galactic Plane.

The Necklace Nebula is the exploded aftermath of a giant star that came too close to its Sun-like binary companion. The two stars that produced the Necklace Nebula are in a relatively small orbit about each other. They have a period of 1.2 days and a separation on the order of 5 times the radius of the Sun.

About 10,000 years ago one of the aging stars ballooned to the point where it engulfed its companion star. The smaller star continued orbiting inside its larger companion, increasing the giant’s rotation rate. The bloated companion star spun so fast that a large part of its gaseous envelope expanded into space. Due to centrifugal force, most of the gas escaped along the star’s equator, producing a ring. The embedded bright knots are dense gas clumps in the ring.>>

[starsurfer]

If you say so. All I can say is that I have not ever seen an example of a PN that appears to have jets. Not that they don't or can't exist.

Some examples of PN with jets:

1. Fg 1
2. Necklace Nebula
3. ETHOS 1

Thanks! Those are the sort of examples I was looking for.

My conclusion is that PNs with jets are extremely rare, but when we see the PNs very early in their development we may encounter them.

Yep they're really rare, some other examples that come to mind are Abell 63 and Sab 41. Some PN have jets that are younger than the main central shell and some of them have ones that are older. When they are caused by an accretion disk, a binary central star (a big topic in PN research) is usually involved.

[starsurfer]

Some examples of PN with jets:

1. Fg 1
2. Necklace Nebula
3. ETHOS 1

The Necklace Nebula

Explanation: The small constellation Sagitta sports this large piece of cosmic jewelry, dubbed the Necklace Nebula. The newly discovered example of a ring-shaped planetary nebula is about 15,000 light-years distant. Its bright ring with pearls of glowing gas is half a light-year across. Planetary nebulae are created by sun-like stars in a final phase of stellar evolution. But the Necklace Nebula's central star, near the center of a ring strongly tilted to our line of sight, has also been shown to be binary, a close system of two stars with an orbital period of just over a day. Astronomers estimating the apparent age of the ring to be around 5,000 years, also find more distant gas clouds perpendicular to the ring plane, seen here at the upper left and lower right. Those clouds were likely ejected about 5,000 years before the clouds forming the necklace. This false color image combines emission from ionized hydrogen in blue, oxygen in green, and nitrogen in red. >>

[b][color=#0000FF]Necklace Nebula, from Hubble Space Telescope, July 2, 2011. Hubble's Wide Field Camera 3 captured the glow of hydrogen (blue), oxygen (green), and nitrogen (red).[/color][/b]

---

<<The Necklace Nebula (PN G054.2-03.4) is a 2 light-year-wide) planetary nebula located about 15,000 light-years away in the northern constellation Sagitta. It was discovered in 2005 from the Isaac Newton Telescope Photometric H-alpha Survey (IPHAS), a ground-based H-alpha planetary nebula study of the North Galactic Plane.

The Necklace Nebula is the exploded aftermath of a giant star that came too close to its Sun-like binary companion. The two stars that produced the Necklace Nebula are in a relatively small orbit about each other. They have a period of 1.2 days and a separation on the order of 5 times the radius of the Sun.

About 10,000 years ago one of the aging stars ballooned to the point where it engulfed its companion star. The smaller star continued orbiting inside its larger companion, increasing the giant’s rotation rate. The bloated companion star spun so fast that a large part of its gaseous envelope expanded into space. Due to centrifugal force, most of the gas escaped along the star’s equator, producing a ring. The embedded bright knots are dense gas clumps in the ring.>>

Check this out:

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