Astronomers have used three telescopes at ESO’s observatories in Chile to observe the dwarf planet Makemake as it drifted in front of a distant star and blocked its light. The new observations have allowed them to check for the first time whether Makemake is surrounded by an atmosphere. This chilly world has an orbit lying in the outer Solar System and was expected to have an atmosphere like Pluto (eso0908), but this is now shown not to be the case. The scientists also measured Makemake’s density for the first time. The new results are to be published in the 22 November issue of the journal Nature.