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We discuss photon and test-particle orbits in the Kehagias-Sfetsos (KS)metric. For any value of the Ho\v{r}ava parameter $\omega$, there are values ofthe gravitational mass $M$ for which the metric describes a naked singularity,and this is always accompanied by a vacuum "antigravity sphere" on whosesurface a test particle can remain at rest (in a zero angular momentumgeodesic), and inside which no circular geodesics exist. The observationalappearance of an accreting KS naked singularity in a binary system would bethat of a quasi-static spherical fluid shell surrounded by an accretion disk,whose properties depend on the value of $M$, but are always very different fromaccretion disks familiar from the Kerr-metric solutions. The properties of thecorresponding circular orbits are qualitatively similar to those of theReissner-Nordstr\"om naked singularities. When event horizons are present, theorbits outside the Kehagias-Sfetsos black hole are qualitatively similar tothose of the Schwarzschild metric.

Circular geodesics of naked singularities in the Kehagias-Sfetsos metric of Ho\v{r}ava's gravity