Deep Imaging Survey - Groth Strip
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Deep Imaging Survey - Groth Strip

April 19, 2005
This is the first image constructed as part of the GALEX Deep Imaging Survey (DIS). This image is taken from a region of the sky called the 'Groth survey strip' named after the principal investigator of a Hubble Space Telescope survey in the constellation Ursa Major (the "Big Dipper").

GALEX observed this region on June 22nd and 23rd, taking 10 exposures during 34 orbits. The NUV detector images were added together to produce this DIS image for a total exposure time of 14,000 seconds. Tens of thousands of objects are detected in this image, the majority are distant galaxies too faint to be detected in single orbit exposures.

The bright streaks near the edge of the image are caused by light from bright stars outside the field of view of the GALEX telescope reflecting at shallow angles off the telescope mirrors. This "stray light" also causes the faint diffuse arc to the lower left of the center of the image. Darker patches in the image are regions where detector "hotspots" have been masked out.

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