Who would have thought that the CO2 debate, which is at the core of the climate change issue, is based on completely uncertain data about the CO2 itself? In fact, we do not know how much carbon from the atmosphere goes where – into the oceans, into trees – or does it remain in the air? That’s why an experimental satellite called BioMass has now been launched, which is supposed to provide exactly these values and will enable a baseline calibration of all calculations. A rather useful project, for whose launch I have come up with an event featuring plenty of greenery, birds‘ chirping, and great experts on stage. BioMass launched successfully on April 29, with a happy audience and a soft toy sloth watching it live at ESA in Darmstadt .