  The microlens parallax is a crucial observable for conclusively identifying
the nature of lens systems in microlensing events containing or composed of
faint (even dark) astronomical objects such as planets, neutron stars, brown
dwarfs, and black holes. With the commencement of a new era of microlensing in
collaboration with space-based observations, the microlens parallax can be
routinely measured. In addition, space-based observations can provide
opportunities to verify the microlens parallax measured from ground-only
observations and to find a unique solution of the lensing lightcurve analysis.
However, since most space-based observations cannot cover the full lightcurves
of lensing events, it is also necessary to verify the reliability of the
information extracted from fragmentary space-based lightcurves. We conduct a
test based on the microlensing event OGLE-2016-BLG-0168 created by a binary
lens system consisting of almost equal mass M-dwarf stars to demonstrate that
it is possible to verify the microlens parallax and to resolve degeneracies by
using the space-based lightcurve even though the observations are fragmentary.
Since space-based observatories will frequently produce fragmentary lightcurves
due to their short observing windows, the methodology of this test will be
useful for next-generation microlensing experiments that combine space-based
and ground-based collaboration.
