An attempt to corral the discussion of the IAU planet definition in one place on planetary.org, so that we may be free to actually discuss Kuiper belt observations and scientific results on posts elsewhere on this site.
On the heels of last weeks reports of a second Sedna and a ringed Centaur comes a third cool outer solar system discovery: A new, likely large member of the Kuiper belt. With an absolute magnitude of about 3.0, the new object currently known as 2013 FY27 is the tenth brightest object beyond Neptune .
On Wednesday, March 26, two important discoveries in the outer solar system were announced: the discovery of the second confirmed member of the Inner Oort Cloud (2012 VP113) and the discovery of rings around the planetesimal Chariklo. In a Hangout on Air, a rag-tag group of planetary scientists and astronomers active on Twitter talked about the discoveries.
2012 VP113 is a new world that has been discovered on a Sedna-like orbit. What does that mean? It could imply the existence of a planet X, but doesn't prove it. It does suggest that a lot more Sednas are waiting to be discovered.
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.
I don’t get much snow in southern California, but I do spend a lot of my time thinking about college snowball experiences and about the snowball fights that have made the objects of the outer solar system.
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."
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.
This month my latest paper made it to print in the Astronomical Journal. It's a short piece that describes a serendipitous discovery that my collaborators and I made while searching for a distant Kuiper Belt Object for the New Horizons spacecraft to visit after its 2015 Pluto flyby.
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.
How come Hubble's pictures of galaxies billions of light years away are so beautifully detailed, yet the pictures of Pluto, which is so much closer, are just little blobs? I get asked this question, or variations of it, a lot. Here's an explainer.