There is controversial evidence about the possible discovery of phosphine in the upper atmosphere of Venus, based on data obtained by various ground- and space-based observations. These data and their analyses are sufficiently complex and subtle as to leave the detection in doubt. To try to place a stringent upper bound of well under one part in ten to the ninth, or to obtain a definitive detection and map its value across the Venusian disk, we intend to investigate the feasibility of a relatively low-cost mission to Venus based on adapting a CubeSat for this purpose. We will determine whether such a satellite can be converted to take high resolution infrared/microwave spectral images of Venus in a flyby mission that would encompass low to high latitudes on Venus, or, preferably, via braking to enter orbit around Venus. We will carry out the needed studies, which involve, for example, propulsion, trajectory, navigation, communication, and data acquisition and transmission.