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Science, Evolution, and Creationism, by the National Academies, focuses on teaching evolution in today's classrooms. Check out the other publications in our online store.
This is a picture of a Brownlee particle, which may be what a comet is made of.
Click on image for full size

Brownlee Particles

This example of Interstellar Dust is a perfect example of the kind of rocky material comet may be made of. The grains themselves seem to be made of smaller grains. There are many holes, or pores. In a proper comet, these holes would be filled with ice.

This example of Interstellar Dust is called a Brownlee Particle after D. E. Brownlee. Dr. Brownlee first detected these particles in the Earth's atmosphere and speculated that they may be the left over remnants of comets which passed through the Earth's orbit. He postulated this theory because of the unusual construction of these rocky particles.

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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