| Description: | The Large Magellanic Cloud, the mini barred spiral galaxy distant by 50 kpc from the Milky Way, has been observed extensively by the ESA-Gaia satellite since 2014. For about 11 million stars, the LMC disc velocity components have been inferred using Gaia astrometry, from which stellar orbits can be studied, and particularly in the region of the LMC bar.
I will present results of measuring the most fundamental parameter of the LMC bar, its pattern speed, by means of three different methods. I will briefly summarize them and demonstrate how the most popular one, which estimated bar pattern speeds for hundreds of galaxies, fails to give a coherent result for the LMC. The most appropriate method involves fitting elliptical orbits and asymmetric rotational motions. It finds a LMC bar pattern speed of ~18.5 km/s/kpc, corresponding to a bar rotation period of 330 Myrs. This makes the LMC hosting a slow bar, which is at odds with most of the fast bars found in the Local Universe.
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