Campus Authors: Michael W. Friedlander

*A Thin Cosmic Rain: Particles from Outer Space*

(Harvard University Press, 2002)

With the discovery, and subsequent study, of cosmic rays came a whole new understanding of how our universe works.

Michael W. Friedlander’s latest book takes the reader through the story of how cosmic rays were accidentally discovered, when they were still thought to be actual rays. But they are now known to not actually be rays, but they are particles — the nuclei of atoms — that are continually raining down on Earth.

It sounds pretty heady, but Friedlander, Ph.D., professor of physics in Arts & Sciences, takes the approach in this book of gearing it to the non-scientist in us all.

“In a previous book, At the Fringes of Science, I was concerned to point to the differences between genuine science and pseudoscience, the ‘science’ of dramatic but unsubstantiated claims,” Friedlander said. “My objective was to describe the method scientific.

“For this new book, I felt that there was a good tale to tell, for cosmic ray particles carry important astrophysical information and also leave traces, souvenirs in many places. Science can be presented to the public at many levels; I have aimed at the interested and curious reader, someone who reads the Scientific American or The New York Times Tuesday science supplements.”

A Thin Cosmic Rain covers more than 100 years of research and explains how cosmic rays are identified and how their energies are measured. It then surveys current knowledge and theories of thin cosmic rain.

“As scientists, we have an obligation to explain to the non-expert public what we are doing, what is exciting about our findings and where we think all of this may lead,” Friedlander said. “In this way, we would hope that the public would gain some understanding of the methods of science, be willing to continue to support our efforts and will also not try to impose ideological restrictions to what we may study.

“History shows that none of this should be taken for granted.”

Cosmic ray research unexpectedly led to the discovery of new particles, such as the muon, pion, kaon and hyperon, andthe research continues to reveal scenes of astounding violencein the cosmos and offers clues about black holes, supernovas, neutron stars, quasars and neutrinos.

With this book, readers see clearly why cosmic rays remain central to an astonishingly diverse range of research studies on scales infinitesimally small and large.

One of the most important byproducts of cosmic rays is the production of carbon 14, which Friedlander covers in a chapter titled “Footprints and Souvenirs.”

“The central point is that carbon 14 is radioactive and has been used to date many archaeological objects,” Freidlander said. “Produced in the upper atmosphere through cosmic ray collisions, the carbon 14 diffuses widely and ends up in plants and the animals that eat them. Measure-ment of the carbon 14 content today permits calculation of the time since that plant or animal died.”

Andy Clendennen