This video shows the tidal disruption of the Antlia 2 dwarf in the Milky Way, accounting for the presence of the Large Magellanic Cloud (LMC) from Ji et al. 2021 ([ Ссылка ]). The left panel shows the evolution in the standard Galactic cartesian coordinates. The right panel shows the evolution in coordinates aligned with the initial angular momentum vector of Antlia 2 with respect to the LMC. The blue points show the particles representing Antlia 2 and its tidal streams. The black dashed curve shows the past orbit of the Antlia 2 for the most recent 250 Myr. The red curve and point show the past orbit and present-day location of the LMC respectively. The green arrow shows the velocity vector of the Milky Way relative to its velocity during Antlia 2's most recent pericenter, when the LMC had not yet accelerated the Milky Way relative to Antlia 2. Since the LMC induces a large downwards velocity in the Milky Way and does not significantly affect Antlia 2, this means Antlia 2 effectively moves upwards relative to the Milky Way since this pericenter. This results in a misalignment between the velocity vector of Antlia 2 and the orientation of its stream (i.e. between the slope of the dashed black line and the blue particles in the right panel). This means that streams like Antlia 2 can be used to infer and measure the motion of the Milky Way. See Ji et al. 2021 ([ Ссылка ]) for more details.

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