Mystery Alignment of Planetary Nebulae Discovered

astroengine writes "Astronomers have discovered something weird in the Milky Way's galactic bulge — a population of planetary nebula are all mysteriously pointing in the same direction. They noticed the mysterious alignment in the long axes of bipolar planetary nebulae. 'This really is a surprising find and, if it holds true, a very important one,' said Bryan Rees of the University of Manchester, co-author of the paper (PDF) to appear in the journal Monthly Notices of the Royal Astronomical Society. 'Many of these ghostly butterflies appear to have their long axes aligned along the plane of our galaxy.' The team of astronomers, who used data from Hubble and the European Southern Observatory's New Technology Telescope (NTT) to survey 130 nebulae, posit that powerful magnetic fields may be behind the phenomenon."

Comments

Bipolar planetary nebula

[dkleinsc]

One moment, they're saying "Yeah, this is great, we're going to make terrestrial and gas giant and ice ball planets and dwarf planets and everything", but before you know it they're just sitting there sulking.

Re:Why is that surprising?

[amicusNYCL]

It makes sense that if all of the stars that formed the nebulae came from the same giant swirling cloud of gas, then the stars formed would tend to have angular momenta mostly aligned upon that same axis. When those stars explode later, the axis of the planetary nebula will be along this same axis.

I was thinking the same thing, but now I'm not so sure. We have at least 8 decent points of data in our solar system for orbital bodies like stars orbiting the center of gravity. Among the 8 planets, 3 of them (Me, V, J) have an axial tilt of less than 4 degrees, 4 of them (E, Ma, S, N) have an axial tilt between 23 and 29 degrees, and one of them (U) is damn near sideways. In other words, our planets are all over the place. So it would seem to make some sense if the stars orbiting the galactic center were also all over the place on their axial tilt, so it wouldn't make sense that the bipolar nebulae are all oriented in the same direction. I wonder how many nebulae this includes though. If it is roughly half of them then that would seem to be in line with our solar system.

Link to the paper in the article is incorrect

[IndigoZulu]

Correct paper: http://www.spacetelescope.org/static/archives/releases/science_papers/heic1316a.pdf