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We propose a novel explanation for the Hercules stream consistent with recentmeasurements of the extent and pattern speed of the Galactic bar. We haveadapted a made-to-measure dynamical model tailored for the Milky Way toinvestigate the kinematics of the solar neighborhood (SNd). The model matchesthe 3D density of the red clump giant stars (RCGs) in the bulge and bar as wellas stellar kinematics in the inner Galaxy, with a pattern speed of 39 kms$^{-1}$ kpc$^{-1}$. Cross-matching this model with the $Gaia$ DR1 TGAS datacombined with RAVE and LAMOST radial velocities, we find that the modelnaturally predicts a bimodality in the $U\!-\!V$-velocity distribution fornearby stars which is in good agreement with the Hercules stream. In the model,the Hercules stream is made of stars orbiting the Lagrange points of the barwhich move outward from the bar's corotation radius to visit the SNd. While themodel is not yet a quantitative fit of the velocity distribution, the newpicture naturally predicts that the Hercules stream is more prominent inwardfrom the Sun and nearly absent only a few $100$ pc outward of the Sun, andplausibly explains that Hercules is prominent in old and metal-rich stars.

Revisiting the Tale of Hercules: how stars orbiting the Lagrange points visit the Sun