Map projections used for star maps

  • I'm working on a star map program and I'm wondering what are the most common map projections used to print star maps...? I want to map of the entire visible sky from a certain point on the surface of Earth. I have all the visible stars and their Altitude-Azimuth, but I need to map this semi-sphere onto a circle in 2D.

    I'd like to get something like this:

    Star map

    I've been playing around with equidistant and gnomonic (-1 RE) projections but they feel too distorted. What are the most common projections used for 2D, circular, entire-visible-sky star maps?

  • Mike G

    Mike G Correct answer

    6 years ago

    The stereographic projection
    Wolfram MathWorld)
    is commonly used for all-sky maps
    Your Sky).
    As distance from the center of the map increases,
    constellations grow larger but keep their shapes.

    Stereographic worked beautifully, thanks!

    Does stereographic projection works also for horizon views?

    @Mr_LinDowsMac Yes, if you can accept a slightly curved horizon. If the view is very wide, a cylindrical projection may be a better choice.

    I found some of your projections here:, and allows to set a horizon marker in some of them. I tried with cyllindrical stereographic, but the problem is to find the right amount of zoom of naked eye user view, there is no FOV field settting.

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