In which direction does the ecliptic plane make an angle of 63 degrees with galactic plane? Is it toward the galactic center? (It can have any 360 degree orientation.)

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    $\begingroup$ You realise this will change as the system orbits the galaxy? So do you mean "currently"? And how would you like it described. $\endgroup$ – Rory Alsop Oct 18 '18 at 22:08

The line defining where the ecliptic plane and the Galactic plane coincide lies (approximately) between the points defined by right ascensions and declinations of 6h +23 and 18h -23.

This can be seen below - the plot is in celestial coordinates with the ecliptic plane marked (thicker solid line) and the Galactic plane clearly visible in the background map of dust extinction.

Galactic and ecliptic planes

The second of these coordinates is close to, but not coincident, with the Galactic centre (marked Sgr A*). So the relative tilt is sort of at right angles to the Galactic centre at present.

Of course this will change over tens of millions of years as the solar system orbits the Galaxy.

  • $\begingroup$ Although the answer above is spot on, I'm sure, I have a hard time visualizing the geometry. To me, there are two angles to consider (maybe three). I would consider the plane of the solar system to be at "right angles" to the galactic plane if the Earth was always at exactly the same distance from Sgr A. If you draw a line in space between the Earth at it's highest point above the galactic plane and it's lowest (6 months later) I would want to know the angle between that line and the one between the sun and Sgr A. The second angle would be if the line was drawn between the 3 and 9 month points $\endgroup$ – Jack R. Woods Nov 12 '18 at 16:16
  • $\begingroup$ @JackR.Woods You imagine a circle defining the ecliptic plane drawn on a horizontal piece of paper. You then tilt the piece of paper and ask what are the coordinates of the two points that intercept the horizontal plane. These are the points on the diagram above where the ecliptic crosses the galactic plane. One of these points is close to the galactic centre. $\endgroup$ – Rob Jeffries Nov 12 '18 at 17:04

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