== Galactic thickness == 

 This article currently says that the Milky Way is "outside the Galactic core, about 1,000 light-years in thickness", but cites no source for this information. I've spent the past half-hour trying to chase down a reliable source for this, but have found only wildly different numbers. Infoplease's "Size and Shape of the Milky Way" (supposedly based on The Columbia Electronic Encyclopedia, 6th ed) claims "its average thickness is 10,000 light-years, increasing to 30,000 light-years at the nucleus" — an order of magnitude larger. One of my old college textbooks, Astronomy, The Cosmic Journey (1982, ISBN 0-534-09576-3, table 23.1, p. 510) gives a table that indicates that we are about 3,300 light-years (1,000 parsecs) from the "edge of the galactic disk in Ζ direction", making the total about 6600 ly (assuming the Sun is very near the galactic plane). Other less reliable sources give numbers typically between 1,000 and 10,000. Oddly, one of the most detailed sources I found (which can hardly be considered reliable) is "A Tour Through the Milky Way" in Star Trek Cartography (STDimension.com), which claims 2,000 light-years "average" thickness (5,000 ly at the center) and states that the Sun is 50 ly off the galactic plane. These are the closest numbers I've seen to my textbook, and gives a possible explanation of the "1,000" number (confusing radial from Z-axis center, or perhaps Sol distance, with thickness). 

 Do we have any solid sources for a thickness of the Milky Way that agree with each other? Ideally, I'd like us to be able to cite figures for the maximum thickness at the center and approximate thickness in our region. (Most informal sources seem to quote "average" thicknesses, which seems an odd datum for either the sphere-like core or the narrowing boundaries of the arms.) Thanks for any assistance. ~