  Irradiated Jovian atmospheres are complex, dynamic, and can undergo temporal
variations due to the close proximity of their parent stars. Of the Jovian
planets that have been catalogued to date, KELT-9b is the hottest Gas Giant
known, with an equilibrium temperature of 4050 K. We probe the temporal
variability of transmission spectroscopic signatures from KELT-9b via a set of
archival multi-year ground-based transit observations, performed with the TRES
facility on the 1.5 m reflector at the Fred Lawrence Whipple Observatory. Our
observations confirm past detections of Fe I, Fe II and Mg I over multiple
epochs, in addition to excess absorption at H-alpha, which is an indicator for
ongoing mass-loss. From our multi-year dataset, the H-alpha light curve
consistently deviates from a standard transit, and follows a 'W' shape that is
deeper near ingress and egress, and shallower mid-transit. To search for and
quantify any seasonal variations that may be present, we parameterise a
'cometary tail' model to fit for the H-alpha transit. We find no detectable
variations between the different observed epochs. Though a 'cometary tail'
describes the H-alpha flux variations well, we note that such a scenario
requires a high density of neutral hydrogen in the n = 2 excited state far
beyond the planetary atmosphere. Other scenarios, such as centre-to-limb
variations larger than that expected from 1-D atmosphere models, may also
contribute to the observed H-alpha transit shape. These multi-epoch
observations highlight the capabilities of small telescopes to provide temporal
monitoring of the dynamics of exoplanet atmospheres.
