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We propose to trace the dynamical motion of a shearing hot spot near theSgrA* source through a dynamical image reconstruction algorithm, StarWarps.Such a hot spot may form as the exhaust of magnetic reconnection in a currentsheet near the black hole horizon. A hot spot that is ejected from the currentsheet into an orbit in the accretion disk may shear and diffuse due toinstabilities at its boundary during its orbit, resulting in a distinctsignature. We subdivide the motion to two distinct phases; the first phaserefers to the appearance of the hot spot modelled as a bright blob, followed bya subsequent shearing phase simulated as a stretched ellipse. We employdifferent observational arrays, including EHT(2017,2022) and the nextgeneration event horizon telescope (ngEHTp1, ngEHT) arrays, in which few newadditional sites are added to the observational array. We make dynamical imagereconstructions for each of these arrays. Subsequently, we infer the hot spotphase in the first phase followed by the axes ratio and the ellipse area in thesecond phase. We focus on the direct observability of the orbiting hot spot inthe sub-mm wavelength. Our analysis demonstrates that newly added dishes mayeasily trace the first phase as well as part of the second phase, before theflux is reduced substantially. The algorithm used in this work can be extendedto any other types of the dynamical motion. Consequently, we conclude that thengEHT is a key to directly observe the dynamical motions near variable sources,such as SgrA*.

Tracing the hot spot motion using the next generation Event Horizon Telescope (ngEHT)