Pale Blue Dot - Carl Sagan [132]
In our fascination with SETI, we might be tempted, even without good evidence, to succumb to belief; but this would be self-indulgent and foolish. We must surrender our skepticism only in the face of rock-solid evidence. Science demands a tolerance for ambiguity. Where we are ignorant, we withhold belief. Whatever annoyance the uncertainty engenders serves a higher purpose: It drives us to accumulate better data. This attitude is the difference between science and so much else. Science offers little in the way of cheap thrills. The standards of evidence are strict. But when followed they allow us to see far, illuminating even a great darkness.
*Surprisingly many people, including New York Times editorialists, are concerned that once extraterrestrials know where we are, they will come here and eat us. Put aside the profound biological differences that must exist between the hypothetical aliens and ourselves; imagine that we constitute an interstellar gastronomic delicacy. Why transport large numbers of us to alien restaurants? The freightage is enormous. Wouldn’t it be better just to steal a few humans, sequence our amino acids or whatever else is the source of our delectability, and then just synthesize the identical food product from scratch?
CHAPTER 21
TO THE SKY!
The stairs of the sky are let down for him that he may ascend thereon to heaven. O gods, put your arms under the king: raise him, lift him to the sky.
To the sky! To the sky!
—HYMN FOR A DEAD PHARAOH (EGYPT, CA. 2600 B.C.)
When my grandparents were children, the electric light, the automobile, the airplane, and the radio were stupefying technological advances, the wonders of the age. You might hear wild stories about them, but you could not find a single exemplar in that little village in Austria-Hungary, near the banks of the river Bug. But in that same time, around the turn of the last century, there were two men who foresaw other, far more ambitious, inventions—Konstantin Tsiolkovsky, the theoretician, a nearly deaf schoolteacher in the obscure Russian town of Kaluga, and Robert Goddard, the engineer, a professor at an equally obscure American college in Massachusetts. They dreamt of using rockets to journey to the planets and the stars. Step by step, they worked out the fundamental physics and many of the details. Gradually, their machines took shape. Ultimately, their dream proved infectious.
In their time, the very idea was considered disreputable, or even a symptom of some obscure derangement. Goddard found that merely mentioning a voyage to other worlds subjected him to ridicule, and he dared not publish or even discuss in public his long-term vision of flights to the stars. As teenagers, both had epiphanal visions of spaceflight that never left them. “I still have dreams in which I fly up to the stars in my machine,” Tsiolkovsky wrote in middle age. “It is difficult to work all on your own for many years, in adverse conditions without a gleam of hope, without any help.” Many of his contemporaries thought he was truly mad. Those who knew physics better than Tsiolkovsky and Goddard—including The New York Times in a dismissive editorial not retracted until the eve of Apollo 11—insisted that rockets could not work in a vacuum, that the Moon and the planets were forever beyond human reach.
A generation later, inspired by Tsiolkovsky and Goddard, Wernher von Braun was constructing the first rocket capable of reaching the edge of space, the V-2. But in one of those ironies with which the twentieth century is replete, von Braun was building it for the Nazis—as an instrument of indiscriminate slaughter of civilians, as a “vengeance weapon” for Hitler, the rocket factories staffed with slave labor, untold human suffering exacted in the construction