This video segment adapted from NOVA shows how Galileo used his telescope to carefully observe and study sunspots.

This video from NASA describes the GLAST satellite, which is equipped with a gamma-ray telescope, and shares some background about the kinds of extreme universal phenomena indicated by the presence of gamma rays.

This video segment from Swift: Eyes through Time introduces and explains theories of the origin of gamma-ray bursts.

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.

Aaron and Justin investigate which sunscreen best keeps out harmful ultraviolet rays from the Sun, in this video from DragonflyTV.

In this video segment adapted from NOVA, explore the theory that small bits of gas and dust combined to form protoplanets billions of years ago, which in turn collided to create the four rocky planets of the inner solar system.

This video segment adapted from the Space Telescope Science Institute shows what the Hubble telescope found when it stared at a single, nearly empty spot in the sky for 10 days in 1995. The unexpected result was a picture of a multitude of galaxies stretching into the distance.

This video segment adapted from NOVA illustrates why carbon is at the center of life on Earth. It also asks whether carbon-based life might exist on other planets.

In this video segment adapted from NOVA, a scientist explains the unexpected heat source fueling widespread volcanic activity on Io, a moon of Jupiter that many had previously assumed to be frozen.

In this video segment adapted from NOVA, scientists are startled to discover evidence for the three key ingredients for life on Saturn's moon Enceladus.

This video segment of Swift: Eyes through Time provides concrete examples to explain the concept that distance in space equals distance in time.

This video adapted from NASA explains how a magnetometer determines magnetic fields around planets.

This video segment produced for Teachers' Domain features a time-lapse video of clouds forming, changing, and moving across the sky.

This brief video segment produced for Teachers' Domain features time-lapse video of a sunrise and a sunset.

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

This video segment adapted from NOVA follows the Apollo 15 astronauts as they collect samples of ancient rock from the Moon's crust, whose discovery helps lead to a radical new theory about the Moon's origin.

Learn about NASA’s Kepler mission and how scientists search for planets orbiting stars outside our solar system in this video segment adapted from NOVA.

This animation adapted from NASA shows the orbital paths of spacecraft in NASA's Earth Observing Fleet that are a source of wide-scale, primary research about Earth.

In this video from DragonflyTV, follow the investigation of Isaac and Anjali as they record, measure, and analyze data about how the Sun's position in the sky affects a solar-powered car's speed.

What is a solar eclipse and why are they only visible in some parts of the world? In this video segment adapted from NASA, astronomer Susan Stolovy uses animations to provide an answer to these questions.