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# Second Example

Another way of creating a WCS object is via the use of a Python dictionary. This affords us more control over the `NAXISn` FITS header keyword which is otherwise automatically default to zero as in the case of the First Example shown above.

    # Define the astropy.wcs.WCS object using a Python dictionary as input

    import astropy.wcs

    wcs_dict = {
        "CTYPE1": "WAVE    ",
        "CUNIT1": "Angstrom",
        "CDELT1": 0.2,
        "CRPIX1": 0,
        "CRVAL1": 10,
        "NAXIS1": 5,
        "CTYPE2": "HPLT-TAN",
        "CUNIT2": "deg",
        "CDELT2": 0.5,
        "CRPIX2": 2,
        "CRVAL2": 0.5,
        "NAXIS2": 4,
        "CTYPE3": "HPLN-TAN",
        "CUNIT3": "deg",
        "CDELT3": 0.4,
        "CRPIX3": 2,
        "CRVAL3": 1,
        "NAXIS3": 3,
    }
    input_wcs = astropy.wcs.WCS(wcs_dict)