The GUVI far ultraviolet imager on the TIMED spacecraft observed a substantial increase in atmospheric dayglow during the M-class solar flare on August 4 2002.   The color image shows a full day of Earth-disk dayglow observations between 50^oN and 50^oS from GUVI's 135.6 spectral channel (dominated by atomic oxygen 135.6 nm emission and corrected for slant path effects) during 14 contiguous TIMED orbits (progressing with time from right to left in the image).   The large black dots show the satellite locations at the times given on the UT scale. The enhanced emission left of image-center (orbit showing satellite location at 10.70 UT) corresponds to the flare, evident also in enhanced solar X-ray (GOES-8) and EUV (SOHO/SEM) fluxes, shown in the panels above the image.   The panels on the right compare the dayglow during the flare orbit (red dots) with the pre-flare orbit (black dots). The two upper panels compare the direct dayglow 135.6 and 135.6/LBH_S observations (where LBH_S refers to a GUVI spectral channel dominated by molecular nitrogen Lyman-Birge-Hopfield band emission). The bottom panel compares Q_EUV between these orbits.   This quantity is the solar energy flux below 45 nm in units of mW m^-2 required to produce the dayglow. It is derived from the combined 135.6 and LBH_S observations (see paper by Strickland et al. [this issue]).