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(3548) Eurybates will be the first Trojan asteroid to be explored in situ when the Lucy spacecraft flies by it in August 2027. The possibility of close-up study of Eurybates. satellite comma Queta comma offers a unique opportunity to test whether Eurybates. unusual properties are tied to its collisional history and comma more broadly comma how collisional evolution shapes small body populations. It is critical to reduce the orbital uncertainty and improve knowledge of the relative position of Queta as soon as possible to understand if there could be an impact to Lucy.s encounter concept of operations and to optimize planning for the best angular resolution and lighting conditions in the brief window when observations can be made. By establishing a tighter constraint on the current orbit comma it will be possible to accelerate searches for non-Keplerian motion should there be an additional satellite or satellites interior to Queta (as are commonly found in other collisional-family satellite systems). Additionally comma we will use astrometric information from trailed stars in the full UVIS aperture to improve predictions for future stellar occultations. HST is required because Queta is 8.7 magnitudes fainter than Eurybates and will be observed at a separation of 0.5 arcsec - an observational regime that is unique to Hubble.