Hi! This is Mooquackwooftweetmeow, a collection of stuff by Greg K Nicholson.
They finally found it - again - another tenth planet, this time unnamed but temporarily designated 2003 UB313. It was also announced yesterday that 2003 EL61 may be roughly 70% Pluto's size.
The press release is now online, as is Mike Brown's Sedna page, at http://www.spitzer.caltech.edu/Media/releases/ssc2004-05/ and http://www.gps.caltech.edu/~mbrown/sedna/ respectively. Right then - Sedna isn't a planet - it's not even a Kuiper Belt Object. According to Mike Brown, the Kuiper Belt has a fairly sharp edge at 50AU (1 Astronomical Unit is the distance from Earth to the Sun, 150 Gm); Sedna comes no closer than 70AU. The appropriate term for Sedna is Inner Oort Cloud Object (and I'd like to take this opportunity to lay claim to the acronym IOCO).
Well, they finally found it, Planet X, a.k.a. Sedna. Of course, if it is decided that it is actually a planet, the name will have to be changed to a Roman god. Sedna is the Inuit goddess of the ocean, and the Roman god of the ocean - Neptune - is already taken.
Officially, Pluto is a planet. In reality, it's a member of numerous Kuiper Belt objects which orbit the Sun beyond Neptune. When it was found, 74 years ago, Clyde Tombaugh was searching for a planet and so assumed what he had found was one.
Questions? Comments? Plaudits? Microblog at identi.ca/gregknicholson, or with the tag #astronomy; or email me at firstname.lastname@example.org.
Big New Tab Button The newest entry: An add-on for Firefox. It makes the New Tab button bigger.
Into the Fire A selected entry: This entry is not a good idea.
Just Give Me A Back Button Another selected entry: An extension to remove the Forward button from Firefox.