This illustration from the Lunar and Planetary Laboratory shows the approximate sizes of the planets relative to each other. Note that the planets are not shown at appropriate distances from the Sun.

This video segment adapted from NOVA features the first planet to be discovered outside our solar system. Its surprisingly large size and short orbit sent scientists back to their data and led them to discover similar planets. [3:06]

Examine the variety of weather found on all of the planets in the solar system with this classroom exercise. Students will see a video and observe differences and similarities among the planets.

Find out how astronomers locate new planets by observing the traits of the stars they orbit. Get some tips at locating stars with the help of star maps.

This activity explores the relative size of the eight planets that circle around the Sun.

This detailed essay defines planets and compares the characteristics to those of Pluto. Orbital graphs and background information clarify the change in Pluto's categorization. A copy of IAU's Resolution 5 is also contained in this essay.

Find out about how planets have been classified historically, and what scientists use to study them.

In this simple lesson, students grow yeast to learn how the climates on each of the nine planets would affect life.

This is a student led activity in which students have to accomplish the task of choosing the most entertaining way to relay written expository information. Art/self expression along with technology are utilized to develop a classroom...

Constellation of articles, images, diagrams, posters, videos, and more on the subject of the search for planets, particularly Earth-like planets, outside our solar system.

Excellent Eight Planets site that provides a vast amount of information about planet Earth. Very comprehensive and complete site.

This Lonely Planet site offers a down-to-earth summary of the culture of Cyprus. Read about ancient relics, religion, and food.

This Eight Planets site briefly describes solar wind, a low density stream of charged particles emitted by the Sun. It also provides the basics on the sun's composition and additional sun links.

Find lots of information about our planet Earth here. Covers basic facts, Earth's history, layers of the Earth, plate tectonics, composition of the atmosphere, Earth's magnetic field, and some facts about our moon.

Olivier Guyon examines the possibility of finding other planets within astronomical numbers, some potentially rife with life. [6:21]

Guide to the best time to view planets.

The purpose of this lesson is to introduce learners to the planet Mars. This lesson will begin by discussing the location and size of Mars relative to Earth, as well as introduce many interesting facts about this red planet. Next, the...

Students must determine mass of a planet based on the orbital motion of a satellite around the planet.

This impressive compilation of ideas is a great source for space science. Loaded with extra links for further information on the solar system.

This site contains copious information about Pluto. The site contains descriptive and statistical information, as well as a detailed article about the search for trans-Plutonian planets and the "Nemesis" hypothesis.

A general introduction to Mars. Includes a glossary of terms and two images of Mars. Many interspersed links to more graphics and more detailed information about the planet Mars. Also includes a printable version and links to other...

Lonely Planet gives some information on the history of Turkmenistan before, during, and after its incorporation into the Russian, then Soviet Empire.

Travel site with stunning photographs from the Lonely Planet offers information on traveling to North Korea, including history, geography and culture.

Until the discovery of Eris, Pluto was known as the largest Keiper belt object. This dwarf planet has replaced Pluto in size and is accompanied by a satellite that has been given the name Dysnomia. Learn about this distant world here...