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"Beyond Pluto, a new frontier of discovery" by Peter N. Spotts is at http://csmonitor.com/2004/1104/p14s02-stss.html .The homepage for "The Christian Science Monitor or csmonitor.com" is at http://csmonitor.com/ .Teresa

The link is at http://skytonight.com/community/skyblog/home/4313977.html .Teresa This morning I found a message in the e-mail inbox from Andrew Fraknoi of Foothill College and editor of the Astronomy Education Review. The note highlights the articles in the latest issue. Among them is "Teaching What a Planet Is: A Roundtable on the Educational Implications of the New Definition of a Planet." The article is an in-depth look at seemingly every issue about the International Astronomical Union's controversial definition of a planet from the points of view of 14 astronomers and educators. Interesting stuff!

I haven't looked through it all yet, but one part that made me pause was that "dwarf" �?as in "Pluto is now a dwarf planet" �?is a problematic word for more reasons than I first considered. It's bad enough that a dwarf star is still a star, and a dwarf galaxy is still a galaxy, but a dwarf planet isn't a planet. In his introduction to the AER article, David Morrison explains: "Although astronomers have a long tradition of using this word (e.g., dwarf star, dwarf galaxy), this is not a common word in general usage. To many people, apparently, dwarf has a negative connotation, which was not intended by the IAU. (There may also be some problems with translating this word into other languages.)"

Check out the article, and . . . discuss!

most recent comment
Planethood for Pluto & Eris
October 9, 2006
Both Pluto and Eris are a little less than one fifth the size of Earth, small seeming perhaps - and, yet, Earth is less than a tenth the size of giant Jupiter! It's all a matter of scale.

Also, a point to appreciate is the presense of a large Moon (both Pluto and Eris have one) changes the whole story. How many scientists would define the diameter of an atom by the width of its nucleus? Pluto and Eris aren't just planets* they are planetary systems with their own substantial
satellites.

Pluto's Moon Charon at 720 miles is actually larger than the giant asteroid - now "dwarf planet" - Ceres.

Eventually I believe Pluto will be reinstated proper to planethood (though perhaps with a distinction, a planet no less) and so then will Eris (Discordia) be upscaled so hopefully this new planet* can be given the rightful name Persephone or Proserpine as suggested by discoverer Mike Brown, Dane Rudhyar and many others.

Until then we may just be stuck with Discord.

–Steven L. Nelson

"Pluto Research" by Dr. Marc W. Buie is at http://www.lowell.edu/users/buie/pluto/pluto.html .This article has pictures and links to different subjects. He is a Pluto supporter. "Pluto IS a planet" is at http://www.lowell.edu/users/buie/pluto/planet.html .Buie's "Definition of a Planet" is at http://www.lowell.edu/users/buie/pluto/planetdefn.html .Buie's "Response to 2006 IAU Resolutions 5a and 6a" is at http://www.lowell.edu/users/buie/pluto/iauresponse.html .The homepage for "Lowell Observatory" is at http://www.lowell.edu/ .For the record, I am a friend and supporter of Lowell. Teresa

The link is at http://dawn.jpl.nasa.gov/feature_stories/ceres_dwarf.asp .This is an article about dwarf planets from NASA. Teresa

Ceres Designated a 'Dwarf Planet' Members of the International Astronomical Union (IAU) gathered at the second General Assembly on August 24, 2006 and voted on an official definition of planet. A "planet" is defined as a celestial body that (a) is in orbit around the Sun, (b) has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a hydrostatic equilibrium and (nearly round) shape, and (c) has cleared the neighborhood around its orbit. It is the last criterion (C) that eliminates Ceres from full planet status. The IAU defined a new category of planets designated as “dwarf planets,�?which have the above properties but reside in a region of the Solar System populated by smaller objects. The current status of planets in the Solar System is the eight classical planets (Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune). Pluto, Charon (its moon), and Ceres are dwarf planets. A dwarf planet is a celestial body that (a) is in orbit around the Sun, (b) has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a hydrostatic equilibrium (nearly round) shape, (c) has not cleared the neighborhood around its orbit, and (d) is not a satellite." + Learn about the IAU Resolutions + Read an opinion of IAU's decision + What are the educational implications of the new definition?

"Why Planets Will Never Be Defined" by Robert Roy Britt is at http://space.com/scienceastronomy/061121_exoplanet_definition.html .Teresa

"All Colonization Should Be Private" by Curran R. Kemp is at http://www.mises.org/story/2421 .Teresa

"New 'Hobbit' Galaxies Discovered Around Milky Way" by Ker Than is at http://space.com/scienceastronomy/070115_mm_hobbit_galaxies.html .Teresa

"NASA Plans a Lunar Rerun" by Bill Walker is at http://www.lewrockwell.com/walker/walker25.html .This is pork in space. Teresa

"New Mexico Lawmaker Petitions to Restore Pluto's Planet Status" by Robert Roy Britt is at http://space.com/news/070309_pluto_resolution.html .Teresa

"Major Discovery: New Planet Could Harbor Water and Life" by Ker Than is at http://www.space.com/scienceastronomy/070424_hab_exoplanet.html .Teresa

The Astronomy Picture of the Day (APOD) for 14 November, 2007 is at http://antwrp.gsfc.nasa.gov/apod/ap071114.html .It is an old picture of the Tunguska (Siberia) meteor impact. Teresa

"The Kepler Mission: The Search for Earth-like Planets" by Leonard David is at http://www.space.com/businesstechnology/070207_kepler_mission.html .Teresa

"Happy Birthday New Horizons! Two Years on the Road to the Ninth Planet" by Alan Stern is at http://pluto.jhuapl.edu/overview/piPerspectives/piPerspectiv... .The home page for New Horizons is at http://pluto.jhuapl.edu/index.php .The home page for NASA is at http://www.nasa.gov/ .Teresa

"Solar Systems Like Ours May Be Rare" by Clara Moskowitz is at http://www.space.com/scienceastronomy/080721-mm-solar-systems.html ."New Video Sees Earth from Alien Perspective" by Andrea Thompson is at http://www.space.com/scienceastronomy/080718-earth-film.html .The home page for "Space.com" is at http://www.space.com/ .Teresa

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