I am very excited about 2015, more so than I have been about any year since I started working at The Planetary Society. Dawn will enter orbit at Ceres, and New Horizons, which will fly past Pluto and Charon. But if we want this kind of exploration to continue, I'm challenging you, dear readers, to tell the world why such non-planetary worlds are compelling places to go exploring.
Just four months ago I posted about a paper recently published by Leslie Young and coauthors that described three possible scenarios for Pluto's atmosphere. Yesterday, Cathy Olkin, Leslie Young, and coauthors posted a preprint on arXiv that says that only one of those scenarios can be true. And it's a surprising one. The title of their paper says it all: "Pluto's atmosphere does not collapse."
New Horizons has just completed a summer of intensive activities and entered hibernation on Aug. 20. The routine parts of the activities included thorough checkouts of all our backup systems (result: they work fine!) and of all our scientific instruments (they work fine too!).
Back in 2005 and 2006, when Pluto’s second and third moons (Nix and Hydra) were discovered, searches by astronomers for still more moons didn’t reveal any. So the accidental discovery of Pluto’s fourth moon by the Hubble Space Telescope in mid-2011 raised the possibility that the hazards in the Pluto system might be greater than previously anticipated.
Last week, I posted an explainer on why Hubble's images of galaxies show so much more detail than its images of Pluto. Then I set you all a homework problem: when will New Horizons be able to see Pluto better than Hubble does? Here's the answer.