Pleiades or Not? Resolving the Status of the Lithium Rich M Dwarfs
  HHJ339 and HHJ430
  Oppenheimer et al. (1997) discovered two M5 dwarfs in the Pleiades with
nearly primordial lithium. These stars are not low enough in mass to represent
the leading edge of the lithium depletion boundary at Pleiades age (~125 Myr).
A possible explanation for the enhanced lithium in these stars is that they are
actually not members of the Pleiades but instead are members of a younger
moving group seen in projection towards the Pleiades. We have used data from
Gaia DR2 to confirm that these two stars, HHJ 339 and HHJ 430, are indeed not
members of the Pleiades. Based on their space motions, parallaxes and positions
in a Gaia-based CMD, it is probable that these two stars are about 40 parsecs
foreground to the Pleiades and have ages of ~25 Myr. Kinematically they are
best matched to the 32 Ori moving group.
