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tokens: UKIRT Infrared Deep Sky Survey (UKIDSS), Bochanski et al. ( 2014 ) were able to identify two stars with distances above 200 kpc, making them the most distant known MW stars. Figure 10 shows that these most distant stars appear consistent with the remote northern stream branch predicted in our simulation. Bochanski et al. ( 2014 ) already associated the M-giants in a distance range of 20–90 kpc in the UKIDSS data with Sgr. However, the more distant detections in their sample were not connected with the stream because the models of Law Majewski ( 2010 ) do not feature stars beyond ∼75 kpc. Our study shows that some of the most distant known MW stars could have originated in Sgr. 4. Discussion and Conclusions We have taken a two-pronged approach to building a new model of the Sgr orbit through the MW halo. Rather than integrate the present-day phase-space coordinates backward in time, we perform an exploration of parameter space with a semianalytic integration of the Sgr trajectory starting 7–8 Gyr ago. This method is chosen because it allows for the inclusion of non-time-reversible effects. In particular, dynamical friction and tidal stripping are expected to be important in the regime where the mass of the Sgr progenitor is ≳10 10 M ⊙ . We then build on these results to simulate the trajectory of Sgr with GADGET and compare the resulting tidal stream to observational data. Our main conclusions are as follows. 1. Comparing the simulated position and velocity of Sgr today to the measured quantities, we find that our analytic model favors a narrow range of the initial orbital angular momentum of Sgr, with large incidence angles ( θ init ≳ 60°) and initial velocities in the range 80 km s −1 ≲ v init ≲ 100 km s −1 . 2. The mock Sgr stream resulting from the GADGET simulation reproduces most of the sky positions, heliocentric distances, and line-of-sight velocities found by 2MASS (Majewski et al. 2004 ). Similarly to previous studies, the line-of-sight velocities of the leading arm are not replicated by the model, suggesting that further work on the triaxiality of the MW halo or the inclusion of the LMC influence is necessary. 3. The simulated debris stream projected on the plane of the Sgr orbit is in unprecedentedly good agreement with the SDSS stellar tracers from Belokurov et al. ( 2014 ). The apocentric distances and position angles of the stream are reproduced to within 20% of the measured values. In particular, the model of the Sgr orbit presented here is the first to naturally reproduce the recently detected distant trailing arm at ∼100 kpc, optimizing only for the remnant coordinates rather than fitting for the stream properties. We believe that this feature arises because of the larger initial separation (125 kpc) used in our simulation compared to other works in the literature (e.g., Law Majewski 2010 ; Purcell et al. 2011 ; Gómez et al. 2015 ). 4. Above all, this work predicts the existence of two novel and distant arms of the Sgr stream.