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We present a novel pair of numerical models of the interaction history between the Large and Small Magellanic Clouds (LMC and SMC, respectively) and our Milky Way (MW) in light of recent high precision proper motions (Kallivayalil et al. 2006a,b). Given the new velocities, cosmological simulations of structure formation favor a scenario where the Magellanic Clouds (MCs) are currently on their first infall towards our Galaxy (Boylan-Kolchin et al. 2011, Busha et al. 2011). We illustrate here that the observed irregular morphology and internal kinematics of the MCs (in gas and stars) are naturally explained by interactions between the LMC and SMC, rather than gravitational interactions with the MW. This picture further supports a first infall scenario (Besla et a. 2007). In particular, we demonstrate that the Magellanic Stream, a band of HI gas trailing behind the MCs 150 degrees across the sky, can be accounted for by the action of LMC tides on the SMC before the system was accreted by the MW. We further demonstrate that the off-center, warped stellar bar of the LMC and its one-armed spiral, can be naturally explained by a recent direct collision with the SMC. Such structures are key morphological characteristics of a class of galaxies referred to as Magellanic Irregulars (de Vaucouleurs & Freeman 1972), the majority of which are not associated with massive spiral galaxies. We infer that dwarf-dwarf galaxy interactions are important drivers for the morphological evolution of Magellanic Irregulars and can dramatically affect the efficiency of baryon removal from dwarf galaxies via the formation of extended tidal bridges and tails. Such interactions are important not only for the evolution of dwarf galaxies but also have direct consequences for the buildup of baryons in our own MW, as LMC-mass systems are believed to be the dominant building blocks of MW-type halos.
The Magellanic Stream and the Leading Arm form a massive, filamentary system of gas clouds surrounding the Large and Small Magellanic Clouds. Here we present a new component-level analysis of their ultraviolet (UV) kinematic properties using a sample
We report the discovery of a nearby dwarf galaxy in the constellation of Hydrus, between the Large and the Small Magellanic Clouds. Hydrus 1 is a mildy elliptical ultra-faint system with luminosity $M_Vsim$ -4.7 and size $sim$ 50 pc, located 28 kpc f
The Magellanic Clouds are surrounded by an extended network of gaseous structures. Chief among these is the Magellanic Stream, an interwoven tail of filaments trailing the Clouds in their orbit around the Milky Way. When considered in tandem with its
The dominant gaseous structure in the Galactic halo is the Magellanic Stream, an extended network of neutral and ionized filaments surrounding the Large and Small Magellanic Clouds (LMC/SMC), the two most massive satellite galaxies of the Milky Way.
We have determined the three-dimensional structure of the Magellanic Clouds and Magellanic Bridge using over $9,000$ Classical Cepheids (CCs) and almost $23,000$ RR~Lyrae (RRL) stars from the fourth phase of the OGLE project. For the CCs we calcula