spacetoday.net: Dwarf planet Makemake lacks atmosphere

Posted: Fri, Nov 23, 2012, 1:45 PM ET (1845 GMT)
Makemake illustration Nov 2012 (ESO)

Astronomers observing a stellar occultation by the dwarf planet Makemake found no evidence of an atmosphere around the distant, icy world. Astronomers observed the occultation using three telescopes at the European Southern Observatory (ESO) in Chile in April 2011 as the dwarf planet, about two-thirds the size of Pluto, passed in front of a distant star. The star abruptly disappeared and then reappeared, a telltale sign that there is no atmosphere around the dwarf planet. Astronomers speculate that the dwarf planet is not massive enough to hold on to an atmosphere. The observations did allow astronomers to refine the density and size of Makemake, including the fact that the world is an oblate spheroid, with axes of 1430 and 1502 kilometers.