Chapter 16: A view from space
Theme: July 1961 to July 1962. This chapter describes the attempts to develop a program of scientific observations for Project Mercury. Initially the program was impeded by the lack of enthusiasm among scientists and the opposition of the project engineers.
Suspended above the earth, enveloped in blackness, the astronaut has a spectacular view of the earth below. Our world is clothed in blue, green, and aqua, trimmed with lacy white clouds. But the view is scientifically revealing as well as beautiful, because so much of the earth’s surface can be seen at one time. This space-eye view banishes the trees and makes clear the outline of the forest Problems with which men have struggled for centuries become clear at a glance. Perhaps no fact was more difficult for men to accept than that the earth is round. With a major intellectual effort, a few of the Greek philosophers came to this conclusion, but the idea was lost again before Columbus’ time. And yet one glance out the Mercury spacecraft window at the clear arc of the horizon demonstrates this beyond doubt. Involved mathematical and philosophical arguments, or long trips across the ocean, are not necessary to prove to the astronaut that the earth is a sphere. He has but to look.
There are many other examples of this same sort of revelation. In the late nineteenth century, the great naval scientist Matthew Maury struggled laboriously with thousands of separate wind direction readings to demonstrate that hurricanes are circular winds moving about a central eye. Yet photographs of Hurricane Debbie taken from the Mercury spacecraft show clearly the spiral arms of clouds circling into the storm’s center. These, of course, are examples of already known facts which can be more dramatically demonstrated with space photography. In addition, there are many new facts which may be learned by putting man’s eye in space.
But it was not easy to develop interest in man as a space scientist. The Mercury engineers were concerned with building vehicles, not in developing uses for them. At the same time, astronomers, astrophysicists, and other basic scientists who might make use of manned space vehicles, were not enthusiastic. Some, having invested great effort in developing telescopes and other earth-based scientific equipment, felt that more could be learned by observations from earth than by putting scientific equipment into space. Other scientists felt that data could be collected most efficiently with automatic equipment in unmanned satellites. Man would only get in the way.
Both John Glenn and Scott Carpenter had a great interest in the scientific observations that could be made from the spacecraft. At John’s urging I attended several meetings of NASA astronomers to get help. While many had deep reservations, Dr. John O’Keefe and Dr. Jocelyn Gill became enthusiastic. They developed a program of observations and John O’Keefe came down to the Cape to brief both John and Scott on what they could do that might be of value to science.
Unfortunately, the malfunction of Friendship 7’s control system occupied John Glenn’s attention and kept him from carrying out most of the scientific observations that he had intended to make. Nevertheless, he did have one surprise which kept John O’Keefe busy over his calculations for some time. During the first orbit as he approached the coast of California just before the sun peeked over the edge of the earth, John looked up to find himself moving through a field of “fireflies.” The sight was beautiful, a complete surprise. At first he felt they must be foreign objects in orbit about the earth. But John O’Keefe’s calculations soon showed that they could not appear to be moving as slowly as John described them unless they came from the spacecraft. This was later proved by Scott Carpenter, who was able to produce clouds of them by tapping the side of the spacecraft, and by Gordon Cooper, who could see them coming from one small jet in front of his window. Apparently they were small ice crystals formed from the thrusters and the water cooling system, and were primarily visible just before sunrise. While this discovery was not of great scientific importance, it illustrated the value of having a man in the spacecraft. Had there been only automatic equipment aboard, we would never have known about the “fireflies.”
John made another more significant observation which was not understood at the time. He saw a hazy layer of light at the horizon during the night. But he over-estimated its height above the horizon so that John O’Keefe, knowing there could not be a layer of material that far out in space, concluded that it must be a reflection in the window from the lights inside the cockpit. Later, Scott Carpenter also reported the haze layer. Like John, he over-estimated its height, but in addition, he made some precise measurements which demonstrated its actual location. Both he and John had been fooled by the natural tendency to over-estimate angular distances at the horizon -- the effect which makes the moon appear larger at the horizon than when it is overhead.
Scott was also able to demonstrate that this hazy layer was related to a phenomenon called “air glow”, with which scientists had been familiar from observations from the earth, but had never been able to see in its full extent. From his flight emerged a picture of the earth, surrounded by a bubble of hazy gas which can be seen by the astronaut at night like a great halo, circling the earth at the horizon. Thus, even when there is no moon to light the earth’s surface, the astronaut will always know where the earth lies.
Other experiments were tried on all the Mercury flights with varying degrees of success. But enough useful information was obtained to interest the scientific community in the opportunities presented by manned space flight. The NASA Office of Space Sciences organized a special division for the purpose of developing research proposals for manned spacecraft, and the National Academy of Sciences began to develop interest in having scientists take part in space flights. Besides demonstrating that man could safely travel in space and operate a space vehicle, the Mercury program had also shown that once there, man could function effectively as a scientist.