Figure: A data cube showing the neutral hydrogen as observed by MeerKAT in the galaxy group around the elliptical galaxy IC 1459. The red cirles denote the Half-Power-Beam-Width (HPBW) and the first Null of the primary beam. Apart from the galaxies, which appear as bright localized features, a faint, intra-group component is detected.


Spiral galaxies are building stars on larger time scales than the depletion time of the gas available in the galaxies themselves. Hence, a replenishment of the star formation reservoirs has to be supplied from the environment. But how this happens in detail is not well known. In the recent years, the question of how galaxies compensate their gas losses through star formation has been targeted by observing also the neutral hydrogen component of galaxies. In this talk I will discuss some recent findings from HI observations in the context of gas accretion and describe how future radio telescopes will help to shed more light into the nature of this process. In particular I will focus on the Karoo Array Telescope, MeerKAT, a new radio interferometer currently being built in the Karoo desert in South Africa. I will discuss its capabilities and the current commissioning status.