The European Space Agency's Planck satellite was launched on 14 May 2009, and has been surveying the sky stably and continuously since 13 August 2009. Its performance is well in line with expectations, and it will continue to gather scientific data until the end of its cryogenic lifetime. I will present the first scientific results of the mission, which appeared as a series of 26 papers at the beginning of this year 2011, covering a variety of astrophysical topics. In particular, I will focus on the results on galactic diffuse emissions, as well as the first results on galaxy clusters detected by means of the Sunyaev-Zeldovich effect.