Database Reference
In-Depth Information
ORDATE = '000503 ' / Observation Ref Date (yymmdd)
DAYNUM = '1160 ' / Observation Day Num
FN_PRFX = 'j1160059' / .rdo and .par filename prefix
TYPE = 'sci ' / Scan type: dar flt sci cal tst
SCANNO = 59 / Scan Number
SCANDIR = 'n ' / Scan Dire ction: n, s, -
COMMENT (OV)
STRIP_ID= 301788 / Strip ID (OV)
POSITNID= 's001422 ' / Position ID (OV)
ORIGIN = '2MASS ' / 2MASS Survey Camera
CTYPE1 = 'RA---SIN' / Orthographic Projection
CTYPE2 = 'DEC--SIN' / Orthographic Projection
CRPIX1 = 256.5 / Axis 1 Reference Pixel
CRPIX2 = 512.5 / Axis 2 Reference Pixel
CRVAL1 = 215.6251831 / RA at Frame Center, J2000 (deg)
CRVAL2 = -0.4748106667 / Dec at Frame Center, J2000 (deg)
CROTA2 = 1.900065243E-05 / Image Twist +AXIS2 W of N, J2000 (deg)
CDELT1 = -0.0002777777845 / Axis 1 Pixel Size (degs)
CDELT2 = 0.0002777777845 / Axis 2 Pixel Size (degs)
USXREF = -256.5 / U-scan X at Grid (0,0)
USYREF = 19556. / U-scan Y at Grid (0,0)
Figure 12.2
(See Color insert following page 224.) Example of image meta-
data in astronomy. On the top is an image of the galaxy NGC 5584, shown at
the center of the purple circle. The image was measured as part of the Two
Micron All Sky Survey (2MASS). The crosses locate the positions of artifacts
in the image. At bottom is a sample of the metadata describing the image,
written in the form of keyword=value pairs, in compliance with the definition
of the Flexible Image Transport System (FITS) in universal use in astronomy.
