It's certainly been a busy day around the world. Mahmoud Abbas title="cbc.ca - Abbas dissolves Hamas Fatah Government">dissolved the Hamas Fatah government and declared a state of emergency in the Gaza Strip and West Bank. The Windows version of Safari has some title="cbc.ca - Security Flaws Found in Safari Web Browser for Windows">pretty alarming security flaws. The title="cbc.ca - Space Station Computers Partially Restored">International Space Stations computers went down, knocking out navigational control and life support. And Pluto lost more ground to other bodies in the solar system.
Since I've never agreed with Hamas' platforms, seldom cared about Apple software, and with the ISS computers are being restored by some of the most skilled people on (and off) the planet, I'd much rather discuss Pluto's continuing slide from the small amount of fame it has achieved in the last century.
When the International Astronomical Union redefined planets last year, it created a new subcategory called "dwarf planets". Pluto was placed into this category along with some other Kuiper Belt and Scattered Disk Objects and was thought to be the largest of them all. However, researchers have recently determined that this is not the case.
Using the Keck Observatory and Hubble telescope, two astronomers were able to calculate the mass of another dwarf planet, Eris, by calculating the movement of its moon, Dysnomia. Armed with this information, they determined that Eris had a mass 27% greater than that of Pluto. That said, this dwarf planet is 1/360th the mass of Earth.
Eris and its moon Dysnomia are the most distant known objects in our solar system, sitting almost 100 Astronomical Units (the distance between the Earth and the Sun) away. It was the discovery of Eris that prompted the IAU's redefinition of a planet. Had Eris been included in the previous definition (anything large enough to be round), it may have increased the number of planets in our solar system to 15.
In the end, the International Astronomical Union decided on a definition that excluded Eris, and by extension, Pluto.