Planet X is dead. (no tenth planet in the solar system)

From: Discover | Date: September 1, 1993| Author: Naeye, Robert | Copyright information

A long quest has ended: there is no tenth planet. But there may be a hundred or a thousand mini-planets in the dark beyond Pluto.

FOR MORE THAN A CENTURY, a few dedicated astronomers have braved the skepticism of their colleagues to champion an alluring idea: the idea that the known planets are not enough. In the dark and frigid boondocks of the outer solar system, these researchers have argued, there lurks a large, undiscovered planet, Planet X, whose gravitational pu...

Read all of this article with a FREE trial to HighBeam Research

Related newspaper, magazine, and journal articles from HighBeam Research

Far out! 12-planet solar system proposed
Deseret News (Salt Lake City) ; PRAGUE, Czech Republic -- The universe really is expanding -- astronomers are proposing to rewrite the textbooks to say that our solar system has 12 planets rather than the nine memorized by generations of schoolchildren. Much-maligned Pluto would remain a planet -- and its largest moon plus two
Scientists think our solar system may have a 10th planet.
Knight Ridder/Tribune News Service ; WASHINGTON _ Our solar system may have a new, strange and very distant member, two teams of astronomers think. It may be a big 10th planet hidden far beyond Pluto, a hitchhiker that joined the solar system later than the rest of the planets. Or it could be a burned-out mini- star, called a brown
It's a big, busy solar system.(TEACHER'S toolkit)
Science Scope ; ... Teachers of inquiry, rejoice! The National Aeronautics and Space Administration (NASA) is a great place to look for the latest news, statistics, and images. Three key pages to bookmark are the NASA Science Mission Directorate's Solar System Exploration web ...
Solar System Update.
Science Scope ; Byline: Bob Riddle This is an artist's impression of noontime on Sedna, the farthest known planetoid from the Sun. During the 20-year period from 1979 to 1999, it was not unusual for solar system savvy students to ask their teacher to name the most distant planet from the Sun. At that time, due to
[ A 2nd red planet in solar system? ... ]
Daily Breeze ; A 2nd red planet in solar system? It's worth thinking about the fact that there is no formal astronomical definition of "planet." Until recently, there has simply been no need to define the term officially. Here in the inner reaches of the solar system it's been quite enough to know a planet when