First, some news. Somewhat obscure news, as I haven't seen the story at any major news outlets*. The number of dwarf planets in the Solar System has increased to four. The list now consists of Ceres, Pluto, Eris, and Makemake. It wasn't that a new body was recently discovered; Makemake (née 2005 FY9
) was discovered over three years ago. Earlier it wasn't known if it met the qualifications to be considered a dwarf planet, but now its application has been accepted, so to speak.
It's kinda neat how symmetric the Asteroid and Kuiper Belts are. If we look at the Asteroid Belt, the largest member is the dwarf planet Ceres. Vying for the #2
spot are Pallas and Vesta, each about a quarter Ceres' mass. (Vesta is a little more massive, but Pallas may be slightly larger in size.) The situation is similar in the Kuiper Belt: #2
, Makemake and fellow applicant 2003 EL61
, are each about 30% of Pluto's mass. (More like 28% if you include Charon.)
But one thing I would like to do is offer praise to Mike Brown, leader of the team that discovered Makemake (and numerous other transneptunian objects), who also came up with the name. As an unhealthy fan of planetary nomenclature, I am very pleased that he took the trouble to come up with an appellation that seems fitting for the object, instead of drawing a random mythological name from a hat. The story behind naming Makemake, which I won't spoil, is on his blog here
* Except Wikipedia. Their front-page news blurbs are excellent at catching major stories that I don't hear about on CNN, the BBC, or elsewhere.
ETA: Well whaddyaknow, it's also tomorrow's APOD
. (The one for 16 Jul 2008.)