Makee: Heliocentric Velocity Correction

WARNING: The December 1998 version of makee contains an error with respect to the new 4-digit year in the DATE-OBS header card. This error may result in an incorrect heliocentric velocity correction. A new version will be available in the near future. For now, you can fix this by manually changing the DATE-OBS card from the YYYY-MM-DD format to DD/MM/YY in your FITS headers. (TAB - 11Nov99)

By default, the "Flux-###.fits" and "Err-###.fits" makee output spectra wavelength scales have been corrected to the heliocentric frame of reference. Thus the motions of the earth around the sun, the earth about it's axis, and the earth around the Sun-Moon center of mass, are taken out of the HIRES spectra wavelength scale. (Note that the Sky-###.fits are NOT corrected to heliocentric.)

Since the motion of the earth about the sun is roughly 30 km/s, this correction can vary by as much as 30 pixels between two exposures taken six months apart (assuming 2.1 km/s/pixel.)

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