Professor John N. Bahcall

Institute for Advanced Study

1 Einstein Drive

Princeton, NJ 08540

November 8, 2001

The Honorable Tom Daschle

United States Senate

Washington, D.C. 20510

Dear Senator Tom Daschle:

I would like to summarize for you the scientific importance of the National Underground Science Laboratory to be located in the Homestake Gold Mine near Lead, South Dakota.

There are pioneering experiments in the fields of physics, astronomy, biology, and geology that can only be carried out in an environment that is shielded from the many competing phenomena that occur on the surface of the earth. These experiments concern such fundamental and applied subjects as: How stable is ordinary matter? What is the dark matter of which most of our universe is composed? What new types of living organisms exist in deep environments from which sunlight is excluded? How are heat and water transported underground over long distances and long times?

American scientists have been among the world leaders in research in these underground studies. But we have had to travel to Japan, to Italy, to Russia, to South Africa, to Finland, to India and to other countries in order to carry out our experiments. During the past year, I had the privilege of chairing a national committee of distinguished research scientists that was charged with the task of recommending whether or not the United States should develop its own national laboratory to support the underground scientific work of physicists, astronomers, biologists, and geologists. We were also asked to make a recommendation as to whether the expenditure of funds for this purpose would, in a highly constrained budgetary situation, be beneficial to the scientific enterprise.

The committee had many meetings in this country and in other countries where major underground scientific facilities are currently active. The committee reached two conclusions. First, it is in the best interests of the United States to develop a national underground science laboratory only if this facility would be the best in the world. Secondly, the Homestake Gold Mine could be converted into the premier underground laboratory in the world. The recommendations of the committee have been endorsed by panels of scientists representing different disciplines.

I hope that these remarks are useful to you and to your colleagues.

Sincerely yours,

John Bahcall

National Medal of Science, 1998