June 1, 2003
President of the United States
Mr. George Bush
The White House
Dear Mr. President
As active scientists we recognize and appreciate your support for the International Space Station (ISS) and we write now to express our strong support for the scientific importance of the International Space Station.
The value and interest of the human exploration of space, for which the space station is essential, has been put forth with considerable clarity and power in the debates taking place since the Columbia disaster, however, we believe that a narrow view has dominated the debates about the scientific importance of ISS. The debate has focused on the earliest work without properly considering the great potential and crucial importance of the Space Station for future science.
Nearly all of the experiments done so far by humans in space have been, necessarily, small in scale. However, the true potential for science in space can only be realized when larger, more complex experimental arrays are also utilized. The experiment which we are planning to mount on the ISS, the Alpha Magnetic Spectrometer (AMS), is an example of such an experiment. AMS is an international collaboration of about 300 physicists from 16 countries. It is supported by NASA and DOE in the United States and by various scientific agencies in the countries of the collaborating institutions. We do not doubt that there will be other equally complex and powerful experiments mounted on the ISS as it matures in its scientific role.
Such experiments benefit in many important essential ways from being resident on the ISS. For example, the space station provides electrical power, spatial orientation, and telemetry to the experiments. These could be provided separately for reach experiment but only at considerable cost and duplication. For major experiments, location on the station offers substantial economy of scale, both in cost and in design and construction time.
The ISS allows experimenters to focus on the scientific design and construction of complex experiments to achieve uncompromised results without the added cost and distraction of also building an independent spacecraft.
Perhaps even more importantly, astronauts and cosmonauts on the ISS provide the possibility for human intervention to repair, modify or respond to unexpected developments. One need only think of the recent experience with the Hubble Space Telescope to appreciate the value of such human intervention. A major experiment involves not only capital costs in the range of billions of dollars, but also many years of development and hundreds, often thousands, of scientific man years. To launch such experiments without the possibility of repair and refurbishment is to accept a level of risk which would seriously impede the research in space, and which is likely to discourage scientists from inventing and working on some of the most important and exciting directions of space science.
In conclusion, we reiterate our strong support for the continued and full development of the ISS.
Donner Professor of Physics
Distinguished Professor of Physics
University of Maryland
Samuel O.C. Ting
Thomas Dudley Cabot Professor of Physics
Massachusetts Institute of Technology
Nobel Prize 1976