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There is ample evidence contradicting the idea that the poles of pulsars are aligned with galactic north-south. Indeed, our own solar system is not aligned wit

There is ample evidence contradicting the idea that the poles of pulsars are aligned with galactic north-south. Indeed, our own solar system is not aligned with galactic north-south, https://commons.wikimedia.org/wiki/File:Motion_of_Sun,_Earth_and_Moon_around_the_Milky_Way.jpg https://commons.wikimedia.org/wiki/File:Motion_of_Sun,_Earth... and that is hardly unusual or unexpected: http://curious.astro.cornell.edu/about-us/159-our-solar-system/the-sun/the-solar-system/236-are-the-planes-of-solar-systems-aligned-with-the-plane-of-the-galaxy-intermediate http://curious.astro.cornell.edu/about-us/159-our-solar-syst... And while we don't have many galactic black hole candidates, the ones we have and can see beaming are haphazardly oriented, and there's no reason why black holes should behave differently from their progenitor stars (oriented haphazardly) or other compact objects (the pulsars mentioned above).

willis936 5y ago
The mass of the solar system is moving in the plane of the galaxy in a rotational direction. If our solar system was accreted by a black hole the solar system would add to black hole's dragged frame rotational energy in the galactic plane. What a few puffs of dust that have not reached an energy minimum yet do isn't important.
- raattgift 5y ago
  As shown in your reply's parent comment which I made, we are not moving in the plane of the galaxy. There is further detail from Ethan Siegel here: https://medium.com/starts-with-a-bang/ask-ethan-37-the-earths-motion-through-the-galaxy-a4787fd46d4b https://medium.com/starts-with-a-bang/ask-ethan-37-the-earth... Quoting a tiny fraction that article: The Sun appears to move *up-and-down* and in-and-out with respect to the rest of the galaxy as it revolves around the Milky Way. (I added the asterisks for emphasis) Additionally, amplifying my previous comment, almost no known black hole candidates' equators are aligned with their host galaxies' thin discs, at any redshift.
  - willis936 5y ago
    You realize that your quote is a lead-in to talk about Earth's procession, yes? You shouldn't suggest that the article is claiming that the Sun's galactic orbit is outside of the galactic plane, because it isn't. >The Sun is presently located about 25-to-27,000 light years from the galactic center, and makes the shape of a simple ellipse around the galaxy.
    - raattgift 5y ago
      You're right that I inadvertently mischaracterized Siegel's article. I expected him to quantify the Z-motion of the solar system in the remainder of the text, and would have known that he did not if I had not lazily and sloppily declined to read the remainder. I simply relied on his reputation as a science popularizer while looking for a popular treatment rather than parametric quantities. Turning to the latter, it is well known that the residual solar motion with respect to the average of local stars is U_sun ~ -10 km s^1, V_sun ~ 5-15 km s^-1, W_sun = 7 km s^-1, leading to the sun moving centre-ward, faster than the local standard of rest, and northward out of the galactic plane. (cf. Dehnen & Binney 1998 [1], and also Schönrich, Binney & Dehnen[2] figures of (U,V,W) = (11.1, 12.24, 7.25) km/s with uncertainties (+0.69-0.75, +-0.47, +0.37-0.36)). Although we are currently close to mid-plane, with a half-period of ~30 million years the solar system for the past six hundred million years has moved in the R,z plane +- 0.075 kpc from the mid-point. This is simply not within the equatorial plane, as opposed to oscillating within the bulk of the stellar disc and through the equatorial plane. The distinction is, in my view, important. So is the point that other local stars move in the z-plane differently. R,\theta is also a bit more complicated than suggested by Siegel's article; the orbit in that plane traces out a rosette shape around the galactic centre.[3] None of this however addresses the key point, which is that the equatorial planes of stellar objects and collapsars are not in general parallel to the equatorial plane of the galaxy, and as a consequence polar jets are not perpendicular to it. The comment several generations up to which you initially replied asked about why the radio-loud steep-spectral-index filaments are all close to perpendicular to the galaxy's equatorial plane. It is a good question, and your answer was not correct. [1] https://academic.oup.com/mnras/article/298/2/387/1056582 https://academic.oup.com/mnras/article/298/2/387/1056582 https://arxiv.org/abs/astro-ph/9710077 https://arxiv.org/abs/astro-ph/9710077 [2] https://academic.oup.com/mnras/article/403/4/1829/1054839 https://academic.oup.com/mnras/article/403/4/1829/1054839 https://arxiv.org/abs/0912.3693 https://arxiv.org/abs/0912.3693 [3] https://www.wolframalpha.com/input?i=parametricplot++%28%28%289.095-0.6375+cos%282*pi+%285-15%29%2F154%29%29+cos+%282*pi*t%2F237%29%2C+%289.095-0.6375+cos%282*pi%28t-15%29%2F154%29%29+sin%282*pi*t%2F237%29%29%2C+%28t%2C+-601%2C+15%29%29 https://www.wolframalpha.com/input?i=parametricplot++%28%28%... for 660 Myr., parameters ibid. & [4], but very much my answer to "show your math". Spatial units are kpc. [4] https://ui.adsabs.harvard.edu/abs/1986gss..conf...35B/abstract https://ui.adsabs.harvard.edu/abs/1986gss..conf...35B/abstra... http://www.as.utexas.edu/astronomy/people/fnb/pubs.html http://www.as.utexas.edu/astronomy/people/fnb/pubs.html

willis936 5y ago

The mass of the solar system is moving in the plane of the galaxy in a rotational direction. If our solar system was accreted by a black hole the solar system would add to black hole's dragged frame rotational energy in the galactic plane. What a few puffs of dust that have not reached an energy minimum yet do isn't important.

raattgift 5y ago
As shown in your reply's parent comment which I made, we are not moving in the plane of the galaxy. There is further detail from Ethan Siegel here: https://medium.com/starts-with-a-bang/ask-ethan-37-the-earths-motion-through-the-galaxy-a4787fd46d4b https://medium.com/starts-with-a-bang/ask-ethan-37-the-earth... Quoting a tiny fraction that article: The Sun appears to move *up-and-down* and in-and-out with respect to the rest of the galaxy as it revolves around the Milky Way. (I added the asterisks for emphasis) Additionally, amplifying my previous comment, almost no known black hole candidates' equators are aligned with their host galaxies' thin discs, at any redshift.
- willis936 5y ago
  You realize that your quote is a lead-in to talk about Earth's procession, yes? You shouldn't suggest that the article is claiming that the Sun's galactic orbit is outside of the galactic plane, because it isn't. >The Sun is presently located about 25-to-27,000 light years from the galactic center, and makes the shape of a simple ellipse around the galaxy.
  - raattgift 5y ago
    You're right that I inadvertently mischaracterized Siegel's article. I expected him to quantify the Z-motion of the solar system in the remainder of the text, and would have known that he did not if I had not lazily and sloppily declined to read the remainder. I simply relied on his reputation as a science popularizer while looking for a popular treatment rather than parametric quantities. Turning to the latter, it is well known that the residual solar motion with respect to the average of local stars is U_sun ~ -10 km s^1, V_sun ~ 5-15 km s^-1, W_sun = 7 km s^-1, leading to the sun moving centre-ward, faster than the local standard of rest, and northward out of the galactic plane. (cf. Dehnen & Binney 1998 [1], and also Schönrich, Binney & Dehnen[2] figures of (U,V,W) = (11.1, 12.24, 7.25) km/s with uncertainties (+0.69-0.75, +-0.47, +0.37-0.36)). Although we are currently close to mid-plane, with a half-period of ~30 million years the solar system for the past six hundred million years has moved in the R,z plane +- 0.075 kpc from the mid-point. This is simply not within the equatorial plane, as opposed to oscillating within the bulk of the stellar disc and through the equatorial plane. The distinction is, in my view, important. So is the point that other local stars move in the z-plane differently. R,\theta is also a bit more complicated than suggested by Siegel's article; the orbit in that plane traces out a rosette shape around the galactic centre.[3] None of this however addresses the key point, which is that the equatorial planes of stellar objects and collapsars are not in general parallel to the equatorial plane of the galaxy, and as a consequence polar jets are not perpendicular to it. The comment several generations up to which you initially replied asked about why the radio-loud steep-spectral-index filaments are all close to perpendicular to the galaxy's equatorial plane. It is a good question, and your answer was not correct. [1] https://academic.oup.com/mnras/article/298/2/387/1056582 https://academic.oup.com/mnras/article/298/2/387/1056582 https://arxiv.org/abs/astro-ph/9710077 https://arxiv.org/abs/astro-ph/9710077 [2] https://academic.oup.com/mnras/article/403/4/1829/1054839 https://academic.oup.com/mnras/article/403/4/1829/1054839 https://arxiv.org/abs/0912.3693 https://arxiv.org/abs/0912.3693 [3] https://www.wolframalpha.com/input?i=parametricplot++%28%28%289.095-0.6375+cos%282*pi+%285-15%29%2F154%29%29+cos+%282*pi*t%2F237%29%2C+%289.095-0.6375+cos%282*pi%28t-15%29%2F154%29%29+sin%282*pi*t%2F237%29%29%2C+%28t%2C+-601%2C+15%29%29 https://www.wolframalpha.com/input?i=parametricplot++%28%28%... for 660 Myr., parameters ibid. & [4], but very much my answer to "show your math". Spatial units are kpc. [4] https://ui.adsabs.harvard.edu/abs/1986gss..conf...35B/abstract https://ui.adsabs.harvard.edu/abs/1986gss..conf...35B/abstra... http://www.as.utexas.edu/astronomy/people/fnb/pubs.html http://www.as.utexas.edu/astronomy/people/fnb/pubs.html