Pluto's Atmosphere Never Completely Disappears

In a Scientific American article dated September 30, 2013, astronomer Dr. Ken Croswell reports the discovery by Dr. Catherine Olkin that Pluto's atmosphere never completely disappears during its 248-year orbit around the Sun. Interestingly, Olkin, of the Southwest Reserarch Institute in Boulder, Colorado, and Dr. John Stansberry of the Space Telescope Science Institute, both agree that Pluto IS a planet--as does Croswell himself. Read the article here: http://www.scientificamerican.com/article.cfm?id=air-apparent-plutos-eternal-atmosphere

The original research paper, to be published in the journal Icarus, can be found and downloaded here: http://arxiv.org/abs/1309.0841