For a time in the late 19th and early 20th centuries, it was erroneously believed that there were canals on Mars.
Maps of the Martian canals. List of Martian Canals. Historical Globes of the Red Planet.
A modern perspective. The Planet Mars: A History of Observation and Discovery .
posted by timshel on Feb 12, 2012 - 26 comments

Scientists have discovered a planet composed of scorching hot ice. Originally thought to be a gas giant due to its mass, its actually only four times the size of Earth and most likely composed of exotic forms of ice, such as Ice VII and Ice X with s surface temperature of 300° C.
posted by Artw on May 16, 2007 - 30 comments

An interactive map of the 174 major meteor impact craters. The largest crater we know of is the Vredefort Dome in South Africa, caused by a meteor some 10 km in diameter. Almost as large in the Sudbury Structure, located in Ontario, which contains some of the world's richest nickel and copper reserves, and has been only confirmed recently to be a crater. Third largest is the now-famous Chicxulub crater in the Yucatan, which probably killed the dinosaurs. Then take a look at an animation of asteroids near Earth [animated gif] and the list of minor planets that could hit us. Want to find out what happens when an meteor impacts in your area? Use the handy Earth Impacts Effects Program!
posted by blahblahblah on Oct 25, 2006 - 13 comments

SAVE PLUTO
posted by thirteenkiller on Aug 25, 2006 - 91 comments

A new planet has been found. The new planet, named 2003 UB₃₁₃ is the farthest known object in the solar system, larger than pluto and a lousy tourist destination. Slacker Astronomy has an interview with co-discoverer Dr. Chad Trujillo.
posted by mosch on Jul 30, 2005 - 39 comments

A Doomed planet orbiting a distant star has been located. No, not Krypton. The planet is going to be consumed by the star soon, but astronomers are not going to wait up for it.
posted by kaemaril on Jan 28, 2003 - 7 comments

Reflections on a Mote of Dust "We succeeded in taking that picture [from deep space], and, if you look at it, you see a dot. That's here. That's home. That's us. On it, everyone you ever heard of, every human being who ever lived, lived out their lives. The aggregate of all our joys and sufferings, thousands of confident religions, ideologies and economic doctrines, every hunter and forager, every hero and coward, every creator and destroyer of civilizations, every king and peasant, every young couple in love, every hopeful child, every mother and father, every inventor and explorer, every teacher of morals, every corrupt politician, every superstar, every supreme leader, every saint and sinner in the history of our species, lived there on a mote of dust, suspended in a sunbeam." Carl Sagan "Pale Blue Dot"
posted by crasspastor on Sep 11, 2001 - 15 comments