Regarding the Upsilon Andromeda System<br />
http://cfa-www.harvard.edu/afoe/upsAnd_pr.html<br />"The discovery of this multiple planet system suggests a new paradigm for planet formation where many small seed planets known as planetesimals might develop in the disk of matter surrounding a star. Those planets that grow fastest would engage in a gravitational tug of war that weeds out some of the smaller worlds and determines which planets ultimately remain in orbit. "The Upsilon Andromedae system suggests that gravitational interactions between Jupiter-mass planets can play a powerful role in sculpting solar systems," said Butler.<br />If these Jupiter-mass planets are like our own Jupiter, they would not be expected to have solid Earth-like surfaces. But, Nisenson noted, "our observations can't rule out Earth-sized planets as well in this planetary system, because their gravity would be too weak for them to be detectable with present instruments."<br /><br />Picture:<br />
http://antwrp.gsfc.nasa.gov/apod/ap990416.html<br /><br />News:<br />
http://www.spacedaily.com/reports/NASA_Spitzer_Sees_Day_and_Night_On_Exotic_World_999.html<br />"Pasadena CA (SPX) Oct 13, 2006<br />NASA's Spitzer Space Telescope has made the first measurements of the day and night temperatures of a planet outside our solar system. The infrared observatory revealed that the Jupiter-like gas giant planet circling very close to its sun is always as hot as fire on one side, and potentially as cold as ice on the other.<br />"This planet has a giant hot spot in the hemisphere that faces the star," said Dr. Joe Harrington of the University of Central Florida, Orlando, lead author of a paper appearing online today in Science. "The temperature differe