Starship Asterisk*

The Helix Nebula from CFHT

Explanation: Will our Sun look like this one day? The Helix Nebula is one of brightest and closest examples of a planetary nebula, a gas cloud created at the end of the life of a Sun-like star. The outer gasses of the star expelled into space appear from our vantage point as if we are looking down a helix. The remnant central stellar core, destined to become a white dwarf star, glows in light so energetic it causes the previously expelled gas to fluoresce. The Helix Nebula, given a technical designation of NGC 7293, lies about 700 light-years away towards the constellation of the Water Bearer (Aquarius) and spans about 2.5 light-years. The featured picture was taken with the Canada-France-Hawaii Telescope (CFHT) located atop a dormant volcano in Hawaii, USA. A close-up of the inner edge of the Helix Nebula shows complex gas knots of unknown origin.

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This is the same one with 2020-11-24 APOD.

Ultiminati wrote: ↑Sun May 07, 2023 5:36 am This is the same one with 2020-11-24 APOD.

Sunday is the day of the Evergreens

The first time I read that the tiny heads of the barely visible knots, excluding their tails, are on average the size of our solar system, and that there are some fourty thousand of them in there, I was impressed! Respect for the mighty eye of the cosmos!

Chris Alex wrote: ↑Sun May 07, 2023 11:40 am The first time I read that the tiny heads of the barely visible knots, excluding their tails, are on average the size of our solar system, and that there are some fourty thousand of them in there, I was impressed! Respect for the mighty eye of the cosmos!

in Solar system we have the Asteroid belt and much more to create super comet tails when Sun goes subgiant to red giant to white dwarf

A beautiful cosmic Tea Rose.

VictorBorun wrote: ↑Sun May 07, 2023 2:24 pm

Chris Alex wrote: ↑Sun May 07, 2023 11:40 am The first time I read that the tiny heads of the barely visible knots, excluding their tails, are on average the size of our solar system, and that there are some fourty thousand of them in there, I was impressed! Respect for the mighty eye of the cosmos!

in Solar system we have the Asteroid belt and much more to create super comet tails when Sun goes subgiant to red giant to white dwarf

Well, the total mass of the asteroid belt is on the order of a small planetary moon (less than 3% of the mass of the Moon). Assuming the Sun even reaches it (which is doubtful) I don't think it will produce significant debris. (And well over half of the mass of the asteroid belt is in just four asteroids.)

Kinda reminds me of the Cat's Eye Nebula! It's a different view of
how it was pictured previously I saw this before in an earlier APOD!

Chris Peterson wrote: ↑Sun May 07, 2023 4:20 pm

VictorBorun wrote: ↑Sun May 07, 2023 2:24 pm

Chris Alex wrote: ↑Sun May 07, 2023 11:40 am The first time I read that the tiny heads of the barely visible knots, excluding their tails, are on average the size of our solar system, and that there are some fourty thousand of them in there, I was impressed! Respect for the mighty eye of the cosmos!

in Solar system we have the Asteroid belt and much more to create super comet tails when Sun goes subgiant to red giant to white dwarf

Well, the total mass of the asteroid belt is on the order of a small planetary moon (less than 3% of the mass of the Moon). Assuming the Sun even reaches it (which is doubtful) I don't think it will produce significant debris. (And well over half of the mass of the asteroid belt is in just four asteroids.)

what, are comet-tail-like features more massive than an asteroid in our Asteroid belt?
Or a Troyan in Jupiter's orbit? A Coiperian?

And the star does not have to reach its asteroids with its dense co-rotating layers; the star has only to blow off a hydrogen-helium shell or two to scrap each time a little matter from the surface of an asteroid in its orbital positions on the moment each wave was passing the orbit… prove me wrong please

VictorBorun wrote: ↑Mon May 08, 2023 11:35 am

Chris Peterson wrote: ↑Sun May 07, 2023 4:20 pm

VictorBorun wrote: ↑Sun May 07, 2023 2:24 pm

in Solar system we have the Asteroid belt and much more to create super comet tails when Sun goes subgiant to red giant to white dwarf

Well, the total mass of the asteroid belt is on the order of a small planetary moon (less than 3% of the mass of the Moon). Assuming the Sun even reaches it (which is doubtful) I don't think it will produce significant debris. (And well over half of the mass of the asteroid belt is in just four asteroids.)

what, are comet-tail-like features more massive than an asteroid in our Asteroid belt?
Or a Troyan in Jupiter's orbit? A Coiperian?

And the star does not have to reach its asteroids with its dense co-rotating layers; the star has only to blow off a hydrogen-helium shell or two to scrap each time a little matter from the surface of an asteroid in its orbital positions on the moment each wave was passing the orbit… prove me wrong please

Asteroids are stony. Nothing to blow off, and not enough heat from the star to vaporize rock. And not enough material to produce a detectable amount of material in any case, even if the entire asteroid were vaporized. The tails we see in APODs like this are solar mass structures.

Chris Peterson wrote: ↑Mon May 08, 2023 1:36 pm

VictorBorun wrote: ↑Mon May 08, 2023 11:35 am

Chris Peterson wrote: ↑Sun May 07, 2023 4:20 pm

Well, the total mass of the asteroid belt is on the order of a small planetary moon (less than 3% of the mass of the Moon). Assuming the Sun even reaches it (which is doubtful) I don't think it will produce significant debris. (And well over half of the mass of the asteroid belt is in just four asteroids.)

what, are comet-tail-like features more massive than an asteroid in our Asteroid belt?
Or a Troyan in Jupiter's orbit? A Coiperian?

And the star does not have to reach its asteroids with its dense co-rotating layers; the star has only to blow off a hydrogen-helium shell or two to scrap each time a little matter from the surface of an asteroid in its orbital positions on the moment each wave was passing the orbit… prove me wrong please

Asteroids are stony. Nothing to blow off, and not enough heat from the star to vaporize rock. And not enough material to produce a detectable amount of material in any case, even if the entire asteroid were vaporized. The tails we see in APODs like this are solar mass structures.

Do I get right?
First there was a core-to-surface shock wave that blew up a surface layer off so it became now the shell and the volume of the nebula.
After the bang there were 10 thousand years of solar wind from the white dwarf so the nebula is kept hot and glowing.

Now at the moment of the bang there were in equatorial belt of the surface of the star some ten thousand super-Jupiter-mass dark spots: electro-magnetic plasma coils; those were solid enough to survive the shock wave. While outside the spots a thin layer got blown off at the speed of 600 km/s, the spots were 10 times more massive for the same area of the shock wave front and, receiving the same momentum, got blown off at the speed of just 60 km/s.

Those coils still travel as whole bodies called knots; while hydrogen shell after 10 thousand years travelled 1.4 ly slowing from 600 km/s to 30 km/s (averaging 42 km/s), the super-Jupiter-knots travelled only half as far averaging just 15 km/s. The stellar wind shadows stretches now all the way from the knots to the shell of the nebula, and the walls of that cones are somehow shining bright.