Why can GALEX observe bright stars? What are the brightness limits?

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Why can GALEX observe bright stars? What are the brightness limits?

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Fundamental detector safety requirements limit observations of bright targets. Currently, point sources, with flat spectra, may not be observed (imaging or grism) that are brighter than: mAB = 9.5 or Fn = 0.6 Jy or Fl = 7 x 10-12 erg cm-2 s-1 -1 in the FUV; mAB = 10.8 or Fn = 0.2 Jy or Fl = 1 x 10-12 erg cm-2 s-1 -1 in the NUV. Bright and / or crowded fields may not be observed if they exceed total brightness levels of : (65000 counts / sec) = Fn = 7.8 Jy or Fl = 9 x 10-11 erg cm-2 s-1 -1 in the FUV; Fn = 2.6 Jy or Fl = 1.5 x 10-11 erg cm-2 s-1 -1 in the NUV. Pointing centers must be separated from bright stars by : 0.75o for an object with Fl = 1 x 10-12 erg cm-2 s-1 -1, or mAB = 10.8 (NUV, ~ 2300 ) (5000cts/s) 0.88o for an object with Fl = 1 x 10-11 erg cm-2 s-1 -1, or mAB = 8.3 (50,000cts/s) 1.00o for an object with Fl = 4 x 10-11 erg cm-2 s-1 -1, or mAB = 6.8 (200,000cts/s) 1.50o for an object with Fl = 1 x 10-10 erg cm-2 s-1 -1, or mAB = 5.8 (500,000cts/s) 2.00o for an object with

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