Use the following lithographs to envision the scale of our solar system. View different models of planets at different scales, an infographic about the relative sizes of the planets and distance from the sun, and images of the largest...

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.

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.

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

Explore the mythology, structure, observational history, gravitational force, and orbit of Earth's Moon.

This site is astronomy for kids and teachers! Here students can learn about the planet Earth of the Solar System including fun facts, mass, day, year, and distance from the Sun.

These hands-on activities are a great way for students to gain perspective on the relative sizes and distances of each planet, the relationship between the sun and Earth, and much more.

Students use water balloons and a length of string to understand how gravity and the velocity of a spacecraft balance to form an orbit. They see that when the velocity becomes too great for gravity to hold onto an object, the object...

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

This is the home page of the team that built the Ultraviolet Imaging Spectrograph carried by the Cassini mission to Saturn.

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.

Describes scientific research into volcanic activity on the surface of Venus. Using information transmitted from the orbiting Magellan spacecraft, data is collected. Includes a glossary of vocabulary terms. [ November 8, 2010]

A brief discussion of the space probes that have reached the planet Venus.

The purpose of this lesson is to teach middle schoolers about how a spacecraft gets from the surface of the Earth to Mars. The lesson first investigates rockets and how they are able to get us into space. Finally, the nature of an orbit...

While astronomers and philosophers have long mused on the possibility of other solar systems, the first planets confirmed to orbit a star other than our Sun weren't found until 1992. The reason it took so long is that it's really hard!...

Students learn how engineers navigate satellites in orbit around the Earth and on their way to other planets in the solar system. In accompanying activities, they explore how ground-based tracking and onboard measurements are performed....

This site from NASA states Kepler's third law of motion and extends it to develop an equation for the velocity of an orbiting planet.

From ABC News in Science, Maggie Fox's article explores a new string of "exoplanets" discovered orbiting distant stars. This research leads to numerous possibilities, one of which being the existence of planetary systems containing life...

How do astronomers collect stardust? They design and build satellites that are launched into space to collect particles on specially designed panels. Satellites can be sent to orbit around an object of interest: a planet, moon, or comet....