3D Space: Illusion or Reality?

This video excerpt from NOVA’s "The Fabric of the Cosmos: What Is Space?" reveals new data about black holes that has led to a new idea about the universe: Instead of everything being a three-dimensional object, it’s possible that everything is actually just a hologram.

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Atoms: The Space Between

This video segment adapted from A Science Odyssey takes a look at the scale of the atom and the tremendous amount of space between the electrons and the nucleus. If all this empty space exists in matter, how can any substance be solid?

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Beyond Einstein

NASA scientists describe some of the ways current science is addressing several of Einstein's fundamental questions and theories in this video adapted from NASA.

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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.

Birth of a Supernova, Type II

In this interactive activity from NOVA Online, learn about a type of exploding star — a Type II supernova — that is so large it has a mass 10 times greater than the mass of our Sun.

Colliding Neutron Stars Create Black Hole and Gamma-ray Burst

This video from NASA describes the detailed computer modeling used to predict that colliding neutron stars can produce gamma-ray bursts similar to those associated with black holes.

Cosmic Origin Spectrograph

This video from NASA features the Cosmic Origin Spectrograph (COS), which allows scientists to use spectrographic analysis to assess the composition of intergalactic material.

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Einstein's Cosmic Speed Limit

This video, adapted from NASA, presents rare experimental evidence from the Fermi Gamma-ray Space Telescope supporting Einstein's prediction that space-time is smooth.

Einstein: A Timeline of His Life

This illustrated timeline from the NOVA Web site follows Albert Einstein's life, including 1905, his "Miracle Year," during which he developed his Special Theory of Relativity and the equation, E=mc².

Einstein: How Smart Was He?

This essay from the NOVA Web site explores the impact Einstein made on physics and most everything we know about the cosmos.

Einstein's Innovative Thinking

Students are introduced to two of Einstein's most famous theories -- special relativity and general relativity -- and what he was thinking when he developed them.

Einstein's Special Theory of Relativity

What happens when you approach the speed of light? This video segment adapted from NOVA follows one of Albert Einstein's thought experiments and his quest to find the answer.

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Einstein's Thoughts on the Ether

Do light waves travel through the ether like waves on a lake travel through water? In this video segment adapted from NOVA, a young Albert Einstein grapples with this question while examining the speed of light.

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The Elements: Forged in Stars

The story of how elements from lithium to uranium are created by stars is illustrated through animation and a hands-on periodic table in this video segment adapted from NOVA.

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Evolution of the Universe

In this video from NASA, learn how the James Webb Space Telescope is helping scientists understand when and how early stars formed, what early galaxies looked like, and how the early universe shaped its underlying structure.

Frames of Reference

Explore how different frames of reference affect your perception of motion in this interactive activity from the American Museum of Natural History.

Gamma Ray Telescope Senses High-Energy Radiation

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.

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.

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History of the Universe

This interactive timeline from the NOVA Web site recaps the theoretical origin and formation of the universe, and forecasts its eventual fate.

How Big Is the Universe?

In this media-rich essay from the NOVA Web site, astronomer Brent Tully of the University of Hawaiʻi walks you through the latest scientific theories about the size of the 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.

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Light Particles Acting Like Waves: The Uncertainty Principle

This video segment adapted from A Science Odyssey uses a laser beam to demonstrate how light particles act like waves, illustrating Heisenberg's Uncertainty Principle.

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The Light Stuff

This interactive activity from the NOVA Web site asks which items in your home can slow down the speed of light.

Light Years

This video segment adapted from Shedding Light on Science describes how astronomical distances can be measured in units of light-years, and how the finite speed of light allows astronomers to study how the universe looked long ago.

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The Michelson Interferometer

Learn about an important physics experiment that uses an invention that manipulates light in this interactive activity adapted from NASA.

Motion and Relativity

This video from the American Museum of Natural History illustrates how motion is described relative to a frame of reference, and how Einstein's special theory of relativity is needed to describe the motion of objects traveling near the speed of light.

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Mystery of the Multiverse

This video excerpt from NOVA’s "The Fabric of the Cosmos: Universe or Multiverse?" explores the idea of the multiverse, stating that there could be multiple universes outside the boundaries of our universe. Statistically speaking, there’s a chance that there’s another Earth out there exactly like ours.

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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.

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Pulsars: Jocelyn Bell

In this video segment adapted from the NOVA, we meet Jocelyn Bell, a graduate student responsible for the discovery of pulsars.

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Pulsars: Little Green Men

The story behind Jocelyn Bell's role in the discovery of pulsars is told in this colorful, comic-book-style resource from A Science Odyssey Web site.

Quantum Mechanics

Are electrons particles or waves? This video segment adapted from A Science Odyssey looks at the intense debate surrounding the understanding of electron configuration.

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Relativity and the Cosmos

This illustrated essay from the NOVA Web site introduces the basic concepts of Einstein's General Theory of Relativity and what we know about cosmology as a result.

Sagan on Time Travel

Astronomer Carl Sagan discusses the possibility of time travel in this audio-enhanced interview from the NOVAWeb site.

Speed of Light: How Fast Is That?

How fast is 300,000 kilometers per second? This text from the NOVA Web site offers a few real-world comparisons for the speed of light.

Speed of Light: Time Traveler

This interactive game from the NOVA Web site explores what happens to time as a traveler approaches the speed of light.

Spin a Spiral Galaxy

This interactive activity from NOVA Online lets you spin a spiral galaxy, including our own Milky Way. It demonstrates that what you can learn from visible light observations of a galaxy is largely determined by the angle from which you are observing it.

String Theory: A New Picture of Gravity

This video segment from NOVA describes the general theory of relativity and the theory of electromagnetism.

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String Theory: A Sense of Scale

This interactive activity from the NOVA Web site puts the infinitesimally small world of string theory into perspective.

String Theory: A Strange New World

This video segment from NOVA chronicles Einstein's quest to unify the forces of electromagnetism and gravity.

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String Theory: A Theory of Everything?

This video segment from NOVA introduces the basic ideas behind string theory and looks at the quest for unification.

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String Theory: A Theory of Everything Essay

In this essay from the NOVA Web site, string theorist Brian Greene introduces the basic ideas behind string theory and how it might help us better understand the universe.

String Theory: Gravity - The Odd Man Out

This video segment from NOVA describes the discovery in the 1930s of two forces in addition to electromagnetism: the strong nuclear force and the weak nuclear force.

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String Theory: Newton's Embarrassing Secret

This video segment from NOVA chronicles Newton's theory of gravity and Einstein's discovery that contradicted it.

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String Theory: Science or Philosophy?

This video segment from NOVA discusses the challenge of proving the scientific validity of string theory, in question because strings may be too small to ever be seen or detected, and therefore tested.

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String Theory: Strings to the Rescue

This video segment from NOVA discusses the challenge of unifying the force of gravity and the forces described by quantum mechanics into a single theory of unification.

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String Theory: The Quantum Café

This video segment from NOVA relates the rise of subatomic physics in the 1920s and the development of the radical theory of quantum mechanics.

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Tangled Up in Teleportation

This video excerpt from NOVA’s "The Fabric of the Cosmos: Quantum Leap" illustrates how quantum entanglement could be used to teleport people from one place to another, and discusses what you would need to make teleportation possible.

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That's My Theory!

Become a game show contestant in this online activity from A Science Odyssey and ask a series of questions to a panel of mystery scientists, using the answers to determine which scientist is Einstein.

Think Like Einstein

This interactive activity from the NOVA Web site challenges you to think like Einstein and understand how time travel might be possible.

Tidal Curiosities

This illustrated essay from the NOVA Web site answers questions about irregularities in the tides.

Time and Relativity

This video from the American Museum of Natural History illustrates Einstein's special theory of relativity and the relationship between time and the motion of objects, including the concept of time dilation.

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Tour of the Electromagnetic Spectrum: Gamma Waves

Get an overview of gamma waves and examples of conditions and events that produce gamma waves, the highest-energy radiation on the EM spectrum, in this video from NASA.

Tour of the Electromagnetic Spectrum: Infrared

Explore the ways scientists use technology to “see” infrared light in this video from NASA.

Tour of the Electromagnetic Spectrum: Microwaves

See microwaves in the context of other areas of the electromagnetic spectrum in this video from NASA.

Tour of the Electromagnetic Spectrum: Radio Waves

This video from NASA provides an overview of the radio band of electromagnetic spectrum and offers a brief history of the discovery and early applications of radio waves.

Tour of the Electromagnetic Spectrum: Ultraviolet

Explore the ultraviolet band of the EM spectrum in this video from NASA.

Tour of the Electromagnetic Spectrum: Visible Light

See just how narrow the visible light band is relative to other EM energy in this video from NASA.

Tour of the Electromagnetic Spectrum: X-rays

Get both an “everyday” and an “exotic” view of x-rays in this video from NASA.

Traveling Through Time

This video excerpt from NOVA’s "The Fabric of the Cosmos: The Illusion of Time" explains gravity’s pull on time, and how time travel may be possible in the future. However, this kind of time travel might not be exactly like Hollywood’s depiction.

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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.

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WMAP: "Baby Picture" of the Universe

View the Wilkinson Microwave Anisotropy Probe (WMAP) image from NASA to see the first detailed map of the oldest light in the universe, from 379,000 years after the Big Bang, over 13 billion years ago. A second image offers a visual timeline to put the WMAP image in perspective.