  We present a new periodogram for periodicity detection in one-dimensional
time-series data from scanning astrometry space missions, like Hipparcos or
Gaia. The periodogram is non-parametric and does not rely on a full or
approximate orbital solution. Since no specific properties of the periodic
signal are assumed, the method is expected to be suitable for the detection of
various types of periodic phenomena, from highly eccentric orbits to periodic
variability-induced movers. The periodogram is an extension of the
phase-distance correlation periodogram (PDC) we introduced in previous papers
based on the statistical concept of distance correlation. We demonstrate the
performance of the periodogram using publicly available Hipparcos data, as well
as simulated data. We also discuss its applicability for Gaia epoch astrometry,
to be published in the future data release 4 (DR4).
