By modelling the axis ratio distribution of SDSS DR8 galaxies we find the intrinsic 3D shapes of spirals and ellipticals. We use morphological information from the Galaxy Zoo project and assume a non-parametric distribution intrinsic of shapes, while taking into account dust extinction.We measure the dust extinction of the full sample of spiral galaxies and find a smaller value than previous estimations, with an edge-on extinction of E 0 = 0.284 +0.015 −0.026 in the SDSS r band. We also find that the distribution of minor to major axis ratio has a mean value of 0.267 ± 0.009, slightly larger than previous estimates mainly due to the lower extinction used; the same affects the circularity of galactic discs, which are found to be less round in shape than in previous studies, with a mean ellipticity of 0.215 ± 0.013.For elliptical galaxies, we find that the minor to major axis ratio, with a mean value of 0.584 ± 0.006, is larger than previous estimations due to the removal of spiral interlopers present in samples with morphological information from photometric profiles. These interlopers are removed when selecting ellipticals using Galaxy Zoo data.We find that the intrinsic shapes of galaxies and their dust extinction vary with absolute magnitude, colour and physical size. We find that bright elliptical galaxies are more spherical than faint ones, a trend that is also present with galaxy size, and that there is no dependence of elliptical galaxy shape with colour. For spiral galaxies we find that the reddest ones have higher dust extinction as expected, due to the fact that this reddening is mainly due to dust. We also find that the thickness of discs increases with luminosity and size, and that brighter, smaller and redder galaxies have less round discs.

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We use the EAGLE simulations to study the effects of the intra-cluster medium (ICM) on the spatially resolved star-formation activity in galaxies. We study three cases of galaxy asymmetry dividing each galaxy in two halves using the plane (i) perpendicular to the velocity direction, differentiating the galaxy part approaching to the cluster center, hereafter dubbed as the "leading half", and the opposite one "trailing half", (ii) perpendicular to the radial position of the satellite to the centre of the cluster, (iii) that maximizes the star-formation rate (SFR) difference between the two halves. For (i), we find an enhancement of the SFR, star formation efficiency (SFE), and interstellar medium pressure in the leading half with respect to the trailing one and normal star-forming galaxies in the EAGLE simulation, and a clear overabundance of gas particles in their trailing. These results suggest that ram pressure (RP) is boosting the star formation by gas compression in the leading half, and transporting the gas to the trailing half. This effect is more pronounced in satellites of intermediate stellar masses 10 9.5−10.5 M , with gas masses above 10 9 M , and located within one virial radius or in the most massive clusters. In (iii) we find an alignment between the velocity and the vector perpendicular to the plane that maximizes the SFR difference between the two halves. It suggests that finding this plane in real galaxies can provide insights into the velocity direction.