How big is the Earth compared to the Sun? Is Mars bigger than the Moon? Seeing all bodies in the solar system larger than 200 miles in diameter side by side provides an excellent comparison and an interesting perspective.

Mathworld states a brief description of a diameter. It also gives a two-dimensional and three-dimensional diagram for a diameter.

This site has a data table of statistical information about Mars. Among the things listed are density, diameter, distance from the Sun, and much more.

This page from NASA provides a chart of statistical information on planet Mercury. Its mass, diameter, average temperature, and distance from the Sun are among the characteristics listed.

The University of North Carolina at Charlotte Chemistry Department provides slides 36-40 of this a 40-slide PowerPoint presentation. The site discuss real gases and the van der Waals equation of state. The explanation for why gas samples...

View satellite images of the Kara-Kul Crater along with data such as its age, diameter, and exact location. The site links with a comprehensive database that allows you to compare impact craters found around the world.

View satellite images of the Siljan Crater along with data such as its age, diameter, and exact location. The site links with a comprehensive database that allows you to compare impact craters found around the world.

View satellite images of the Manicougan Crater along with data such as its age, diameter, and exact location. The site links with a comprehensive database that allows you to compare impact craters found around the world.

View satellite images of the Popigai Crater along with data such as its age, diameter, and exact location. The site links with a comprehensive database that allows you to compare impact craters found around the world.

View satellite images of the Morokweng Crater, along with data such as its age, diameter, and exact location.

This resource lists basic data for the Kara impact crater. This data includes facts on the crater's exact location, diameter and age.

View satellite images of the Beaverhead Crater along with data such as its age, diameter, and exact location. This site links to a world map which contains locations and data for other impact craters.

View satellite images of the Charlevoix Crater along with data such as its age, diameter, and exact location. The site links with a comprehensive database that allows you to compare impact craters found around the world.

This site has many useful formulas and examples relating to circles, including related definitions, circumference of a circle, area of a circle, length of a circular arc, area of a circular sector, equation of a circle in cartesian...

The National Oceanic and Atmospheric Administration provides a photo library of severe weather formations. This photograph of a hailstone is measured on a ruler to indicate a diameter of 6 inches (approximately the size of a grapefruit).

The National Oceanic and Atmospheric Administration provides a photo library of severe weather formations. This photograph of a hailstone is measured on a ruler to indicate a diameter of 4 inches (approximately the size of a baseball).

WebMath offers a great site for students to practice finding the diameter, area and circumference of a circle.

A plan of the ground floor of the Capitol Building from 1825. The map is keyed to show: (A) House of Representatives, 96 feet radius; (B) Senate Chamber, 75 feet radius; (C) Central Rotunda, 96 feet in diameter; (D) Library, 92 x 34...

The 53 m high tomb built in ad 1006 for Qabus Ibn Voshmgir, Ziyarid ruler and literati, near the ruins of the ancient city of Jorjan in north-east Iran, bears testimony to the cultural exchange between Central Asian nomads and the...

The United States' largest cone-shaped burial mound, 62 feet (19 m) tall, 240 feet (73 m) diameter at base.

An image of "Window", created by Duccio Di Buoninsegna in 1288 (Stained-glass, diameter: 700 cm).

An image of "Desco da parto (recto)", created by Bartolomeo Di Fruosino in 1428 (Tempera on panel, diameter 59 cm).

An image of "Desco da parto (verso)", created by Bartolomeo Di Fruosino in 1428 (Tempera on panel, diameter 59 cm).

An image of "Leonello d'Este", created by Pisanello in 1444 (Bronze medal, diameter 6,7 cm).