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Fraser
2006-May-12, 12:16 AM
SUMMARY: These photographs are composite images of various planetary nebulae created out of data from the Hubble Space Telescope and Chandra X-Ray Observatory. The Chandra data (in blue) shows the X-ray view while Hubble (red and green) reveals the optical view. As a massive star nears the end of its life, it expels material to surround itself in a dusty shroud. The intense ultraviolet radiation from the star heats up the material and forces it away at extremely high speeds. This creates the unusual shapes we see from Earth.

View full article (http://www.universetoday.com/am/publish/chandra_dying_stars.html)
What do you think about this story? post your comments below.

Jerry
2006-May-12, 02:14 PM
This mass loss creates a more or less spherical cloud around the starNo, this cloud is not spherical, it very clearly has two lobes!

Since the 'clouds' are very often a pair of lobes extending in opposite directions, it is reasonable to argue that there is a yet-to-be understood axis of symetry in many of these events. Is this a binary pair? Is there a linear accelerator of some kind that dominates late in the life of a star? Are there other massive objects that are syphoning away the nebula? How does the axis of the gas clouds relate to the rotational axis of the star? Are there planetary masses involved? I wish these articles were written more in the context of what is not known or poorly understood, rather than as rather dry statements that imply the process is well defined.

homer308
2006-May-23, 04:35 PM
Good morning!

I have ALWAYS wondered about the lobes on most stellar explosion events - I've searched for further info, both here and elsewhere, but been unsuccessful to date. My query is so obvious, I know it must have been researched and/or debunked by now, but I haven't found out either way!

My query:

Is angular momentum of sufficient magnitude in rapidly spinning stars, that, at the moment of collapse and reduced diameter, the spin rate increases enough to flatten the stellar core? If this body was distorted enough into a disk-like form, is it plausible/possible that there would be significant gravitational reduction at the spin axis? If so, would this reduction be enough that the internal pressures could cause the core to erupt/explode along that same spin axis?

This would account for your posted "axis of symmetry" in these events - the type of post-collapse lobes/jets observed would be dependent on the size and rate of rotation of the pre-collapse star.

Maybe I'm all wet, but as this scenario fits the principles of Occam's Razor, it IS a tidy solution to the comment on the original story about "The origin of the funnel-shaped winds is not understood".

Forgive my ignorance in these matters as I am not professionally trained; just an amateur lover of the sky and all it contains! If this has been shown incorrect or is overly simplistic, please let me know! If anyone has any reference sources I could get to help me get self-educated on this topic, I would deeply appreciate it!

Any comments are welcome - this has been driving me mad for a LONG time!

First post - just found you guys!

From a devoted backyard Dobsonian junkie!

Dave
Kenosha, WI