The following table describes the FITS header for EUV combined-frame images in the EUV FITS archive and full-frame EUV images. For more information on the FITS standard, please see Definition of the Flexible Image Transport System (FITS).
keyword | definition | system | units | comments |
---|---|---|---|---|
SIMPLE | standard FITS header? | boolean | - | always true |
BITPIX | bits per pixel | - | - | 32 bit IEEE floating point pixel values |
NAXIS | image dimensions | - | - | always 2 |
NAXIS1 | horizontal image dimension | - | pixels | 140 for standard EUV fits images, 600 for full-frame images |
NAXIS2 | vertical image dimension | - | pixels | 150 for standard EUV fits images, 140 for full-frame images |
LINEAR | counts in the image are linear? | boolean | - | very early FITS images had logarithmic counts |
OVERLAP | pixel overlap used when combining the images from the 3 cameras | - | pixels | |
TAU | spins per frame | - | spins | this is always 5 (so far) |
IMTIME | camera 0 start time | - | - | This shouldn't be used, use JUL_DAY instead to define the frame time |
IMAGE_X | IMAGE satellite X position | GCI | km | |
IMAGE_Y | IMAGE satellite Y position | GCI | km | |
IMAGE_Z | IMAGE satellite Z position | GCI | km | |
IMAGE_VX | IMAGE satellite X velocity | GCI | km/sec | |
IMAGE_VY | IMAGE satellite Y velocity | GCI | km/sec | |
IMAGE_VZ | IMAGE satellite Z velocity | GCI | km/sec | |
SUN_X | Sun X position | GCI | km | |
SUN_Y | Sun Y position | GCI | km | |
SUN_Z | Sun Z position | GCI | km | |
MOON_X | Moon X position | GCI | km | |
MOON_Y | Moon Y position | GCI | km | |
MOON_Z | Moon Z position | GCI | km | |
IMAGELAT | IMAGE satellite latitude | GCI | degrees | |
IMAGELON | IMAGE satellite longitude | GCI | degrees | |
IMAGWLON | IMAGE satellite West longitude | GEO | degrees | |
IMAGSLON | IMAGE satellite Solar longitude | GCI | degrees | angle of the Sun from IMAGE (increasing eastward) |
SPINAXX | IMAGE satellite spin axis X component | GCI | - | unit vector |
SPINAXY | IMAGE satellite spin axis Y component | GCI | - | unit vector |
SPINAXZ | IMAGE satellite spin axis Z component | GCI | - | unit vector |
JUL_DAY | Julian day of midpoint of the combined EUV frame | days |