The Survey dictionary contains classes that support ground based sky surveys.
A location on the celestial sphere, consisting
of right ascension and declination.
The position of one corner of an
image
The portion of the sky contained within an
image, identified by its four corners
The limiting magnitude of the
image
The limiting magnitude of a point source at a
significance of n-sigma (i.e. a S/N of n)
The limiting magnitude of the image, expressed
as a magnitude, and the percentage of known objects detected at
that magnitude
The properties of the peak of the histogram of
stellar magnitudes within the image.
Sky Survey related properties.
This section contains the simpleTypes that provide more constraints
than those at the base data type level. The simpleTypes defined here build on the base data
types. This is another component of the common dictionary and therefore falls within the
common namespace.
The band for which the limiting magnitude
specification is applicable
Further classifies calibration images by the
type of calibration field used.
Identifies which corner of the image is being
located. This assumes that the image is displayed correctly
according to the orientation information provided in the display
dictionary
The declination component of a coordinate,
decimal degrees
Time that defines the origin of a celestial
coordinate system, given in fractional year. Type of year may
also be indicated. For example, 'J2000.0' corresponds to an
origin specified by January 1, 2000 at 12:00 Terrestrial Time in
Julian years.
Project-dependent field ID
Magnitude at which a threshold known objects are
detected
Represents the value of n for n-sigma limiting
magnitude: The limiting magnitude of a point source at a
significance of n-sigma (i.e. a S/N of n)
Identifies the intent of the observation,
whether it is an actual survey observation, a followup, or a
calibration image.
Further classifies survey observations by the
technique used to acquire it.
The percentage of known objects that are
detected at the given magnitude for the specified
band
The type of observed object used to calculate
the limiting magnitude
The right ascension component of a coordinate,
decimal degrees
The full width at half maximum of stellar
sources at the magnitude of the peak of the histogram of stellar
magnitudes in the image, in arcseconds
The magnitude of the peak of the histogram of
stellar magnitudes in the image.
The SNR at the magnitude of the peak of the
histogram of stellar magnitudes in the image.