The article states that they think it might be related to interaction with the galaxy's magnetic field. Makes sense since the field is stronger as you approach the galactic core. PN are what's left of very old stars, so they've had lots of time to get tweaked by the galaxy's field. On Thu, Sep 5, 2013 at 12:46 PM, Joe Bauman <josephmbauman@yahoo.com> wrote:
It's really intriguing, Dan. Maybe this is some effect of dark energy or dark matter. I would have thought it was because the entire galaxy's stars have a similar orientation while forming, maybe due to the galaxy's rotation -- but that's disproved by the fact that more distant nebulae are not oriented in any special way like these toward the center of the galaxy. Thanks, Joe
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