Subtopic: Composition of the Universe

All Planet Sizes
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.

Astronomical Images in Different Wavelengths
Visible light is just one portion of the electromagnetic spectrum that a telescope may detect. This collection of images produced for Teachers' Domain features radio wave, infrared, visible light, and X-ray images of distant stars and galaxies as well as images of the telescopes designed to detect the various wavelengths of radiation.

Birth of a Supernova, Type Ia
In this interactive activity from NOVA Online, learn about a type of exploding star — a Type Ia supernova — that is so bright that astronomers can measure the distance to the galaxy in which it resides, and even learn which elements make up the star.

Caves: Extreme Conditions for Life
This video segment adapted from NOVA raises the provocative idea that if life can exist in the most extreme environments on Earth — such as in dark, toxic caves — then perhaps living things can also survive in harsh environments on other planets.

Earth, the Universe, and Culture
The following lesson will help the students understand the cultural nature of scientific research.

Explore the Moon
See what it is like to walk on the Moon by viewing this collection of QuickTime images from NOVA Online. Stunning 360-degree panoramas from each of the six successful Apollo Moon landings are featured.

Galileo: Discovering Jupiter's Moons
This video segment adapted from NOVA shows how Galileo, using his newly developed refracting telescope, observed four of Jupiter's moons, the first astronomical bodies to be discovered since ancient times.

Galileo: Sun-Centered System
In the early 1600s, most people believed that the Sun revolved around a stationary Earth. This video segment adapted from NOVA tells how Galileo proved that the Sun, not Earth, is at the center of our universe.

Gallery of Auroras
View this stunning collection of auroral displays from NOVA Online to find out why auroras appear in different colors and shapes and whether they occur on other planets.

Gravity and the Expanding Universe
This video segment, adapted from NOVA, traces the evolving history of theories about gravity and a force that may oppose it, along with our understanding of the impact of both of these forces on our expanding universe.

Hubble's Expanding Universe
This adapted video segment, using footage from NOVA and NASA, examines Edwin Hubble's work and how his findings laid the foundation for the Big Bang theory.

Infrared Search for Origins
This interactive resource from NASA illustrates how infrared technology has advanced space exploration and can offer insight into questions about star formation, planetary systems, brown dwarfs, and the origins of the universe.

Ingredients for Life: Water
This video segment adapted from NOVA goes on a whimsical journey in search of life forms thriving in extreme conditions on Earth and in outer space. Animations show ice on Jupiter's moon, Europa, and signs that water once existed on Mars.

Mars Dead or Alive: A Hostile Environment
This NOVA video segment describes the challenges presented by the frozen desert environment of Mars to NASA engineers designing two robots that will journey millions of miles to the red planet.

Mars Dead or Alive: Welcome to Mars
This video segment from NOVA features the dramatic landing of the Spirit and Opportunity rovers on Mars.

Meteor Showers
This video segment adapted from NASA uses animation to illustrate the properties of meteor showers and comets. Included is are visualizations of a comet's tail and of Earth passing through a debris stream left behind by meteoroids.

The Origin of the Elements
This video segment adapted from NOVA explains the origin of the elements and how scientists use unique element profiles to identify supernova types.

Phases of the Moon
When we look up at the night sky, why do we see the Moon's appearance changing over time from a full sphere to a crescent to nothing at all? Find the answers in this interactive resource adapted from the National Air and Space Museum.

The Relationship Between Science and Technology
Students will learn how technology can help scientists solve a problem. One of the challenges scientists face with any spacecraft is attitude control. Students will be introduced to the problem of attitude control in space and two different ways scientists address it.

Solar Wind's Effect on Earth
This video segment adapted from NASA describes solar storms and their effects on Earth. Animations of coronal mass ejections and solar cycles help explain what we know, and what we can predict, about solar activity.

A Strange New Planet
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.

Theories
This lesson will help the students understand that science theories change in the face of new evidence, but those changes can be slow in coming.

Universe Origins
This video segment from Swift: Eyes through Time covers gamma ray bursts; geocentric and heliocentric models; and, cultural interpretations of scientific data.

What Is a Planet?
This video segment, adapted from NOVA scienceNOW, presents the ongoing debate over the definition of a planet, including the status of Pluto.

Why Doesn't the Moon Fall Down?
In this animated video segment adapted from NASA, astronomer Doris Daou explains how the forces of speed and gravity keep the Moon in a constant orbit around Earth.