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The W. M. Keck Observatory has generated an observatory wide strategic plan for 2035. This plan has identified visible Adaptive Optics (AO) as an attractive science path for the observatory. Given the 10-meter aperture of the Keck telescopes, a visible AO system can achieve extremely high spatial resolutions. These high resolutions will be comparable to that of Extremely Large Telescopes (ELTs) in the infrared, which can lead to synergistic observations between the observatories. To demonstrate the feasibility of visible AO we have recently installed a visible camera (ORKID) that works behind AO as part of the ORbiting Configurable Artificial Stars (ORCAS) mission. ORCAS is a first-of-its-kind hybrid space and ground observatory, using a satellite-based laser as the AO beacon for wavefront sensing. As a risk reduction for ORCAS we have demonstrated the opportunistic use of a passing asteroid (known as an appulse) as a source for AO wavefront sensing on UGC 4729, an object where there is no viable nature guide star for AO observations. To demonstrate the angular resolution of the Keck telescopes at visible wavelengths we have used the ORKID camera to image a number of targets including the close binary Theta Orionis C. The binary is detected at a separation of 44.4 mas, with a FWHM of 15.1 mas at 650nm. This is the sharpest point spread function (PSF) ever measured at Keck demonstrating the potential offered by visible AO. These two demonstrations show the potential for high resolution visible AO science. We present the rational for pushing to the visible, results from ORKID, results of our appulse demonstration, and our AO development plans that will enable high resolution visible AO at the W.M. Keck Observatory.
