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The massive binary system Eta Carinae is characterized by intense collidingwinds that form shocks and emit X-rays. The system is highly eccentric($e\simeq0.9$), resulting in modulated X-ray emission during its 5.54 yearorbit. The X-ray flux increases in the months prior to periastron passage,exhibiting strong flares, then rapidly declines to a flat minimum lasting a fewweeks, followed by a gradual recovery. We present Neutron Star InteriorComposition Explorer (NICER) telescope spectra obtained before, during, andafter the 2020 X-ray minimum, and perform spectral analysis to establish thetemporal behavior of X-ray flux and X-ray-absorbing column density ($N_{\rmH}(t)$) for the 2-10 keV and 5-10 keV energy ranges. The latter range isdominated by the stellar wind collision region and, therefore, these spectralparameters - in particular, $N_{\rm H}(t)$ - serves as a potentially stringentconstraint on the binary orientation. We compare the observed $N_{\rm H}(t)$results to the behavior predicted by a simple geometrical model in an attemptto ascertain which star is closer to us at periastron: the more massive primary($\omega \simeq 240$-$270^\circ$), or the secondary ($\omega \simeq 90^\circ$).We find that the variations in column density, both far from periastron andaround periastron passage, support the latter configuration ($\omega \simeq90^\circ$). The 2020 X-ray minimum showed the fastest recovery among the lastfive minima, providing additional evidence for a recent weakening of theprimary star's wind.

The X-ray properties of Eta Carinae during its 2020 X-ray minimum