Article outlining the scientific history behind the discovery of black holes. The writer discusses how scientific theories guide scientists in creating explanations for natural phenomena.

A black and white photo of Albert Einstein. Check out our Albert Einstein facts page for more information on this famous scientist.

A very lengthy page from friesian.com discussing Bohr's theory of electronic energy levels and the explanation of commonly observed atomic emission line spectra. The concept of a photon and Einstein's observation of the photoelectric...

Read this article to help understand and describe Einstein's general theory of relativity.

A portrait of Albert Einstein from the Dibner Library of the History of Science and Technology, made available through the Smithsonian Institution's Scientific Identity Collection.

A portrait of Albert Einstein from the Dibner Library of the History of Science and Technology, made available through the Smithsonian Institution's Scientific Identity Collection.

A portrait of Albert Einstein from the Dibner Library of the History of Science and Technology, made available through the Smithsonian Institution's Scientific Identity Collection.

A portrait of Albert Einstein from the Dibner Library of the History of Science and Technology, made available through the Smithsonian Institution's Scientific Identity Collection.

A portrait of Albert Einstein from the Dibner Library of the History of Science and Technology, made available through the Smithsonian Institution's Scientific Identity Collection.

A portrait of Albert Einstein from the Dibner Library of the History of Science and Technology, made available through the Smithsonian Institution's Scientific Identity Collection.

Fear of Physics uses animations and simple language to teach the theory of relativity.

Investigate the wavelength properties of visible light and the scattering effects of the earth's atmosphere on different wavelengths.

Investigate problem-solving techniques by using observation and data analysis skills. Observe how different people solve the same puzzle and make conclusions about how humans and animals think.

Investigate the communication skills of animals. Explore their ability to associate abstract concepts or signs with specific objects or actions by solving a puzzle involving decoding symbols.

Investigate the work of ethologists - animal behaviorists - by observing an animal's behavior (alone and then in a group) for an extended period of time. Produce a scientific report of your observations.

Explore the theory that animals can learn to comprehend abstract concepts by observing to see if specific animal calls are associated with specific actions. Use scientific observation and record-keeping to collect and analyze data.

Flip over this interactive OLogy card and start learning bite-size pieces of useful information about E = mc^2, Einstein's famous equation that shows the relationship between mass and energy.

What is known about gravity? Find out Einstein's thoughts on gravity in a brief overview of this mysterious force.

A decent explanation of the concept of time as the fourth dimension. The author discusses Einstein's theory of special relativity and the idea of space-time.

[Free Registration/Login may be required to access all resource tools.] Explores the conservation of mass and energy in nuclear reactions and Einstein's equation.

[Free Registration/Login Required] Test your understanding of falsifiable hypotheses.

This site examines the black hole as an object in astrophysics. Delve into this comprehensive resource that covers this concept from its history, to qualitative physics, the reality of black holes, mathematical physics and more.

PBS offers a short summary of the discovery of the quantum nature of the atom by Max Planck. Easy to follow.

A history of the science of cosmology, the study of the universe, and the scientists who did pioneering work in this field in the twentieth century.