This document presents a number of theories, both plausible and implausible or even humorous, for the extinction of the dinosaurs. Links to a glossary are embedded in the text. A reading list and links to related sites are also provided.
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This movie shows a total eclipse of the Sun which occurred in 1994. It is accompanied by a link to a written description of the Sun's physical characteristics.
This tutorial explains some of the techniques developed by astronomers to determine the distances of objects we see in the sky. Links to additional information are embedded in the text.
This site presents graphic plots of solar wind and magnetic field data from the Advanced Composition Explorer (ACE) spacecraft.
This site presents information about the Advanced Composition Explorer (ACE) spacecraft and its mission, science goals, history, and background. The mission summary includes a brief description of the energetic particles from the sun and from interstellar and galactic sources that are the objectives of the ACE mission. Links to additional information are also supplied.
This is the homepage of the American Geological Institute (AGI). Visitors can access information about geoscience education, public policy, environmental geoscience, careers in geoscience, publications, news articles, and events. Materials presented here include databases, curriculum materials, legislation and appropriations information, and an image bank.
This timeline chronicles the history of space science and astronomy, and places it in the broader context of the history of society and technology. It begins in 13000 B.C. with the arrival of humans in America, and ends in 2003. Links to additional material on certain topics and persons are embedded in the text.
This lithograph provides a full-disk view of Earth photographed by Apollo 17 astronauts, Dec. 7, 1972. The accompanying text describes the view seen in the photograph and the circumstances in which it was taken. Suggestions for activities in which the photograph can be used are also provided.
The goal of this project is to establish a privately owned, permanent, self-supporting base on the Moon. Materials presented here include plans for a lunar habitat, mining on the Moon, and commercial space flights to the Moon.
These views of asteroids were imaged at close range by the Galileo and Near Earth Asteroid Rendezvous (NEAR) spacecraft. They are presented at the same scale, and images of Mars' moons, Phobos and Deimos, and Ida's moon Dactyl are also shown. The accompanying text provides a description of the images, some historical facts and statistical data, along with significant dates in asteroid exploration.
This training module was designed to help the user identify and grasp basic concepts associated with space travel and deep space missions. Separate sections deal with topics such as the physical environment of space (solar system, gravity, orbital mechanics), flight projects (mission concepts, system requirements, design, onboard systems and instruments), and flight operations (launch, cruise, encounter). Links to related topics are embedded in the text.
This collection of images, movies, and animations from NASA's Solar and Heliospheric Observatory (SOHO) features a large selection of images of the sun and of solar phenomena. Although most of the imagery is of the sun, a few images of comets and planets as they transit the solar disk are available.
This tutorial provides a basic discussion about crystallography. Text and diagrams explain how crystals are measured, classified, and described, and point out that minerals can be identified by their crystal shapes and growth habits.
This webpage provides a calculation tool to aid in the creation of a scale model of the Solar System. The program computes model planet sizes and distances using an initial model Sun diameter, entered by the user. It also provides other interesting data, such as actual and scaled distances and sizes of stars and galaxies.
This site describes bouyancy (the difference between the upward and downward forces acting on the bottom and the top of an object) and the Archimedes Principle, which states that the buoyant force on a submerged object is equal to the weight of the fluid that is displaced by it. It consists of text descriptions of these principles, using the examples of metal cubes suspended in water and hot air baloons in the atmosphere. Mathematical word problems are included.
This activity has students create a Cartesian diver, which will act in some ways like a submarine. Students will adjust the amount of air and water in an inverted test tube (the "diver") so that it at first barely floats in a water-filled bottle. Then, they will squeeze the closed bottle to create higher water pressure, causing the diver to sink. Releasing the bottle allows the diver to float again. Written instructions, a list of materials, and illustrations are included.
Visitors to this site can examine and download materials that provide information and activities about the Chandra mission. These materials include a coloring and activity book, a tutorial and trading cards about Chandra, information on galaxies and the X-ray universe, and paper models of Chandra and other observatory satellites.
This site, originally published as part of NASA's History Series, presents a detailed history of the Apollo program. The story begins in the 1950s with early efforts to beat the Soviet Union into space, carries through the Kennedy administration, with its famous challenge to land a man on the moon and return him safely to Earth by the end of the 1960s, and culminates with the landing of Apollo 11 on the Moon in July 1969. The site features text, pictures, references, and several appendices containing more detailed information.
With graphics and a brief video clip, the Coriolis effect is concisely and effectively explained. This site is part of the WW2010 Project and features current weather data and detailed explanatory/instructional material as well as curricular materials, archived products and case studies.
This resource offers access to a variety of materials, including general information about COOL, a photo gallery, press releases, talks and papers, and research projects. There are links to archived and real-time ocean data (sea surface temperature, surface currents and waves, autonomous glider data), and an "underwater weather forecast".