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Basic Information on cotra

Task: cotra
Purpose: coordinate transformations
Categories: utility

        COTRA is a MIRIAD task to transform between astronomical coordinate
        systems.  The coordinate systems must be one of:
        equatorial, galactic, ecliptic, super-galactic
        For given galactic longitude,latitude, it also shows three conversions
        for common velocity frames of reference:
        dVlsr  = Vlsr  - Vbsr     (BSR = Heliocentric)
        dVgsr  = Vgsr  - Vlsr
        dVlgsr = Vlgsr - Vgsr
        In addition, several conversions between doppler velocities
        can be calculated (optical, radio, relativistic)

Key: radec
        Input RA/DEC or longitude/latitude. RA is given in hours
        (or hh:mm:ss), whereas all the others are given in degrees
        (or dd:mm:ss). There is no default.

Key: type
        Input coordinate system. Possible values are
        "b1950" (the default), "j2000", "galactic", "ecliptic"
        and "super-galactic". b1950 and j2000 are equatorial coordinates
        in the B1950 and J2000 frames. All other coordinates are in the
        B1950 frames.

Key: epoch
        Epoch (in standard Miriad time format) of the coordinate. Note
        that this is distinct from the equinox of the coordinate as given
        above. Varying epoch changes the coordinate values by less than an
        arcsecond. The default is b1950.

Key: uvw
        Standard Solar motion in right handed UVW coordinate system.
        The classic value of 20 km/s toward RA,DEC=18h,30d corresponds to
        uvw=10.3,15.3,7.7 but is using too high a value
        for V. A bettter, Hipparchos based, value would be
        Default:   9,12,7

Key: theta0
        LSR speed in km/s. Default: 220
        The GSR motion (-62,40,-35) is currently hardcoded.

Key: z
        Redshift (unitless) or velocity (km/s).
        If velocity is given,  the optical or radio definition
        in a 2nd argument needs to be specified. Valid are
        'o' (optical), 'r' (radio) and 'x' (relativistic).
        Default : 0

Key: restfreq
        Rest frequency of a spectral line in GHz.
        Default: 115.271204 (the CO 0-1 transition)

Generated by miriad@atnf.csiro.au on 21 Jun 2016