Mr. Steven Weinberg has long been a vocal critic of NASA's manned spaceflight program, recently questioning the scientific usefulness of the International Space Station in particular, and asserting that the entire manned spaceflight program has produced nothing of scientific value.

The National Space Society, composed of members who promote mankind's future of living and working in space, strongly supports NASA's manned spaceflight program, and disagrees with both the spirit and substance of his comments.

For a first response, we turn to another renowned physicist, Dr. Stephen Hawking, who has urged the human race to "spread out into space for the survival of the species." Hawking states the increasing risk of being wiped out by a disaster, such as sudden global warming, nuclear war, or some other unknown danger as the primary reasons to diversify humanity's future beyond earth.

NASA has numerous examples of "spinoffs" from the space program, such as kidney dialysis machines, fetal heart monitors, programmable heart pacemakers, to name just a few that help Americans every day. Additionally, the International Space Station operations enable NASA to learn valuable scientific information about the long term effect of spaceflight on the human body, and how best to help humans adapt themselves for long trips, either in interplanetary space, or enroute to planets such as Mars.

While these are all important, they don't compare to the effect these achievements have on the human spirit. Many of us still remember the first time we saw Earth from the Moon's orbit, when the astronauts of Apollo 8 filmed it on Christmas Eve, in 1968. Many argue this global awareness started the conservation movement, which might turn out to be the space program's greatest spinoff, and may save the earth's climate in the long run. Many of us were inspired when we saw the astronauts walk on the Moon, and realized that if mankind could do that, we could do almost anything. The achievements of NASA's unmanned spacecraft are phenomenal, and deserving of acclaim, but they don't lift people's spirits to these heights.

Weinberg should understand that many citizens don't understand the benefits of theoretical physics to their own lives, and question the utility of the nation's investment in such work. That is an alternate explanation to why the Superconducting Super Collider was de-funded: Congress was not convinced of the utility of spending $12 billion on the project. Here is where we can observe a certain parallel with spaceflight: Both spaceflight and particle physics are basic investments in the future.

As the President stated during his Vision for Space Exploration speech, "The cause of exploration and discovery is not an option we choose; it is a desire written in the human heart." The National Space Society members support living and working in space, and the hundreds of people who have already bought their own suborbital spaceflight tickets are further proof that this is a vision that is spreading. For all the good NASA's manned spaceflight program has brought us, at the meager budget levels they're provided, we should be thanking and praising them for their dedicated perseverance.

It is not possible to predict all of the benefits that either the human space program or particle physics research will do for our country, but that does not mean that the searches are not worthy. It is important for us to pursue, and solve, the deepest questions of the universe, just as it is important for us to explore our solar system and eventually live beyond the confines of our home planet. Our descendents will thank us for both pursuits.

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George Whitesides is the executive director of the National Space Society.

NOTE: The views of this article are the author's and do not reflect the policies of the National Space Society.

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