A dwarf planet is a celestial body orbiting the Sun that is massive
enough to be spherical as a result of its own gravity but has not
cleared its neighbouring region of planetesimals and is not a
satellite. They are smaller than planets, but more massive than small
solar system bodies. The term was adopted in 2006 by the International
Astronomical Union (IAU) as a result in the increase in discoveries of
trans-Neptunian objects that rivaled Pluto in size, and finally
precipitated by the discovery of an even more massive object, Eris. The
IAU currently recognizes five dwarf planets—Ceres (pictured), Pluto,
Haumea, Makemake, and Eris. It is suspected that at least another 40
known objects in the Solar System are dwarf planets, but the number
might be as high as 2,000. The 2006 definition has been both praised
and criticized, and has been disputed by some scientists.
Read the rest of this article:
<http://en.wikipedia.org/wiki/Dwarf_planet>
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Today's selected anniversaries:
755:
In Tang Dynasty China, An Lushan revolted against Chancellor Yang
Guozhong, initiating the An Shi Rebellion, which lasted eight years
before it was put down.
<http://en.wikipedia.org/wiki/An_Shi_Rebellion>
1497:
On his way to India, Vasco da Gama and his crew passed the Great Fish
River on the Cape of Good Hope, becoming the first Europeans to sail
into the Indian Ocean.
<http://en.wikipedia.org/wiki/Vasco_da_Gama>
1689:
The Parliament of England adopted the Bill of Rights, declaring that
Englishmen possessed certain positive civil and political rights.
<http://en.wikipedia.org/wiki/Bill_of_Rights_1689>
1960:
United Airlines Flight 826 and Trans World Airlines Flight 266 collided
in mid-air in heavy clouds over Staten Island, New York City, killing
134 people.
<http://en.wikipedia.org/wiki/1960_New_York_air_disaster>
1997:
"Dennō Senshi Porygon", an episode of the Japanese television series
Pokémon, induced epileptic seizures in 685 children.
<http://en.wikipedia.org/wiki/Denn%C5%8D_Senshi_Porygon>
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Wiktionary's word of the day:
bookish (adj):
1. Given to reading; fond of study; better acquainted with books than
with people; learned from books.
2. Characterized by a method of expression generally found in books
<http://en.wiktionary.org/wiki/bookish>
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Wikiquote quote of the day:
The only way of discovering the limits of the possible is to venture a
little way past them into the impossible.
--Arthur C. Clarke
<http://en.wikiquote.org/wiki/Arthur_C._Clarke>