We combine Spitzer and ground-based observations to measure the microlens parallax vector { \mbox { \boldmath$ \pi$ } } _ { E } , and so the mass and distance of OGLE-2014-BLG-0124L , making it the first microlensing planetary system with a space-based parallax measurement .
The planet and star have masses m \sim 0.5 M _ { jup } and M \sim 0.7 M _ { \odot } and are separated by a _ { \perp } \sim 3.1 { AU } in projection .
The main source of uncertainty in all these numbers ( approximately 30 % , 30 % , and 20 % ) is the relatively poor measurement of the Einstein radius \theta _ { E } , rather than uncertainty in \pi _ { E } , which is measured with 2.5 % precision , which compares to 22 % based on OGLE data alone .
The Spitzer data therefore provide not only a substantial improvement in the precision of the \pi _ { E } measurement but also the first independent test of a ground-based { \mbox { \boldmath$ \pi$ } } _ { E } measurement .