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Description
The NEAT/SkyMorph survey provides access to the archives
of the Near Earth Asteroid Tracking (NEAT) project. NEAT is
designed to look for potentially hazardous asteroids, i.e., those
whose orbits cross the Earth's. Over 200,000 images are available
in the NEAT archive.
<a href=https://skyview.gsfc.nasa.gov/skymorph/skymorph.html>SkyMorph</a>
provides a Web interface to the NEAT
images and allows users to select all images in which a given fixed
or moving object is found.
<p>
Unlike most <i>SkyView</i> surveys, the NEAT data are extremely irregular in their
spatial distribution. <i>SkyView</i>'s algorithms for mosaicking images
together to form large images are not adequate for the NEAT data, so
mosaicking is surpressed. Only data within a single NEAT image will
be displayed. The system attempts to find the most recent image within
which has a offset in both RA and Dec of less than 0.8 degrees. If no
such image is found, then an image with the minimum offset is returned, or
the search may fail altogether if there are no nearby plates.
The NEAT telescope uses an array of 4 CCDs. The backgrounds of the
CCDs may differ significantly.
<p>
The NEAT survey covers approximately 30% of the sky. Extreme southern
and low-Galactic latitude regions are unsurveyed. Coverage is otherwise
particularly dense in the ecliptic plane.
<p>
NEAT data consists primarily of groups of three images taken with separations
of 20 minutes and almost identical positions. <i> SkyView </i> will normally
return the last of a 'triplet'. The SkyMorph site can be used to display
an overlay of triplets to look for targets which moved during the interval
between images.
<p>
A catalog of objects detected in the NEAT/SkyMorph pages is accessible
through the SkyMorph pages. 'Light-curves' from all images during which
an object was in the NEAT field of view can also be generated.
<P>
The NEAT data values are in arbitrary density units. To enhance the display
data are transformed such that all pixels below the median values
are scaled linearly to values 0-20, while all pixels above the median
are shifted (but not scaled) to values greater than 20.
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