Shop Windows to the Universe

Become a nitrogen atom in the nitrogen cycle in our Traveling Nitrogen Classroom Activity Kit/Game. See all our games, activity kits and classroom activities.

A Matter of Scale

Last modified September 1, 2010 by Randy Russell.

Shop Windows to the Universe Science Store!

The Fall 2009 issue of The Earth Scientist, which includes articles on student research into building design for earthquakes and a classroom lab on the composition of the Earth’s ancient atmosphere, is available in our online store.

Windows to the Universe Community



You might also be interested in:

The Cosmic Microwave Background Radiation

In the 1960's another startling discovery was made quite by accident. A pair of scientists at Bell Laboratories detected some annoying background noise using a special low noise antenna. The strange thing...more


Archaea was originally thought to be just another form of bacteria, but archaea is a much simpler form of life, simpler than a single-celled organism, which nevertheless contains DNA, the gene-code of...more

The Cosmos

Cosmology is the study of the overall structure of the universe. And just what is the Universe? Quite simply, it is everything that exists. However, from Earth we cannot observe everything in the Universe....more

Elliptical Galaxies

Elliptical galaxies are generally egg-shaped. If you have the chance to see one through a small telescope, it will probably look just like a fuzzy smudge to you, a piece of lint. But it is really formed...more

Globular Clusters

If you think that this globular cluster looks like a very round elliptical galaxy, you would be right! Elliptical galaxies and globular clusters have a lot in common. There is no gas or dust in a globular...more

Large-Scale Structure: Your Place in the Universe

When we look out into the Universe we observe some rather remarkable structure. We have seen that stars cluster together to form galaxies. But galaxies also cluster together to form much larger structures....more

Irregular Galaxies

Irregular galaxies are appropriately named. This class includes any galaxy which cannot be classified as either spiral or elliptical. Thus in some sense every irregular galaxy is unique in it's appearance....more

Atomic Nucleus

Atoms are composed of a massive, central nucleus surrounded by a swarm of fast-moving electrons. The nucleus is made up of protons and, in most cases, neutrons. Almost all of the mass (more than 99%) of...more

Windows to the Universe, a project of the National Earth Science Teachers Association, is sponsored in part is sponsored in part through grants from federal agencies (NASA and NOAA), and partnerships with affiliated organizations, including the American Geophysical Union, the Howard Hughes Medical Institute, the Earth System Information Partnership, the American Meteorological Society, the National Center for Science Education, and TERC. The American Geophysical Union and the American Geosciences Institute are Windows to the Universe Founding Partners. NESTA welcomes new Institutional Affiliates in support of our ongoing programs, as well as collaborations on new projects. Contact NESTA for more information. NASA ESIP NCSE HHMI AGU AGI AMS NOAA