As it turns out most cataclysmic variable stars have as one of its members a white dwarf. Most of these are visible in small,10" or bigger, telescopes. Jerry Foote ScopeCraft, Inc. 4175 E. Red Cliffs Dr. Kanab, UT 84741 435-899-1255 jfoote@scopecraft.com
Why do you suppose Roy Bishop disagrees with you? On Sat, Jan 24, 2009 at 6:23 PM, Jerry Foote <jfoote@scopecraft.com> wrote:
As it turns out most cataclysmic variable stars have as one of its members a white dwarf. Most of these are visible in small,10" or bigger, telescopes.
This is an interesting thread. Funny how a person can pick up notions that are wrong. I always thought the barely visible white dot in the center of the Helix nebula was a white dwarf but it isn’t; but if we keep looking it may be. Wikipedia says: The Helix Nebula is an example of a planetary nebula, or 'planetary' formed at the end of a star's evolution. Gases from the star in the surrounding space appear, from our vantage point, as if we are looking down a helix structure. The remnant central stellar core, known as a planetary nebula nucleus or PNN, is destined to become a white dwarf star. jg
That's how I understand it. The nebula itself is just short-lived "puff", and the white-dwarf stage comes long after the nebula has vanished. 2009/1/24 Jim Gibson <jimgibson00@yahoo.com>
This is an interesting thread. Funny how a person can pick up notions that are wrong. I always thought the barely visible white dot in the center of the Helix nebula was a white dwarf but it isn't; but if we keep looking it may be.
Wikipedia says: The Helix Nebula is an example of a planetary nebula, or 'planetary' formed at the end of a star's evolution. Gases from the star in the surrounding space appear, from our vantage point, as if we are looking down a helix structure. The remnant central stellar core, known as a planetary nebula nucleus or PNN, is destined to become a white dwarf star.
jg
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Jerry, now I'm thinking that the white dwarf companions to those cataclysmic variables are probably not visible. What is visible is the larger star and the hot material spilling onto the dwarf. Is that what you meant? Or did you mean that the dwarves themselves are directly visible? This seems to be what Bishop is stating; that only the two examples are easily observed. On Sat, Jan 24, 2009 at 7:57 PM, Chuck Hards <chuck.hards@gmail.com> wrote:
Why do you suppose Roy Bishop disagrees with you?
participants (3)
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Chuck Hards -
Jerry Foote -
Jim Gibson