To the engineers on Katherine’s desk fell the responsibility of the trajectories, tracing out in painstaking detail the exact path that the spacecraft would travel across Earth’s surface from the second it lifted off the launchpad until the moment it splashed down in the Atlantic. As the head of the Space Task Group, Robert Gilruth had been given his pick of NASA employees to fill the ranks of Project Mercury’s nerve center. Katherine’s office mate, John Mayer, had jumped ship for the new endeavor a week after it was created, in November 1958. The workload generated by Project Mercury was so onerous that even after Mayer transferred from 1244 to the offices on the East Side, he “bootlegged” the overflow work to his old buddies Carl Huss and Ted Skopinski, getting them to help out with whatever time they could squeeze in around what they owed to Henry Pearson. He got them to do “computing runs” for him—which meant getting Katherine to do computing runs for them. The group took on the additional tasks with zeal, because space looked like “a hell of a lot of fun.” They turned their desks into a trigonometric war room, poring over equations, scrawling ideas on blackboards, evaluating their work, erasing it, starting over.
There was virtually no aspect of twentieth-century defense technology that had not been touched by the hands and minds of female mathematicians. Like Katherine and her colleagues at Langley, women at the Aberdeen Proving Ground in Maryland spent thousands upon thousands of woman-hours computing ballistics trajectory tables, which soldiers used to accurately calibrate and fire their weapons, as Jim Johnson had in Korea. The first attempt to put a man into space, NASA decided, should be a simple ballistic flight, with the capsule fired into space by a rocket like a bullet from a gun or a tennis ball from a tennis ball machine. Capsule goes up, capsule comes down, its path defined by a big parabola, its landing place the Atlantic Ocean. The astronaut needed to return near enough to waiting navy ships to be quickly hoisted out of the water and pulled to safety. The challenge was to rig the machine’s position so that the ball—the Mercury capsule—landed as closely as possible to the navy’s waiting racket. Calculated incorrectly, the ball would go out of bounds, the astronaut’s life endangered. The math had to be as precise and accurate as an Althea Gibson serve.
A well-executed suborbital flight would buy the United States a little breathing room; but orbital flight—the end game of Project Mercury—was infinitely more complex. Successful orbital flight required the engineers to adjust the tennis ball machine’s chute to the correct angle and arm its launcher with enough force to send the ball up through the atmosphere and into an orbit around Earth on a path so precisely specified, so true, that when it came back down through the atmosphere, it was still within spitting distance of the navy’s waiting racket.
“Let me do it,” Katherine said to Ted Skopinski. Working with Skopinski as a computer (or “math aide,” as the women had been renamed when the NACA became NASA), she had proven herself to be as reliable with numbers as a Swiss timepiece and deft with higher-level conceptual work. She was older than many of the space pilgrims, some of whom were just out of college, but she matched them at every turn for enthusiasm and work stamina. The fellas were putting everything they had on the line, and she was not going to be left out. “Tell me where you want the man to land, and I’ll tell you where to send him up,” she said.
Her grasp of analytical geometry was as good as that of the guys she worked with, perhaps better. And the unyielding demands of Project Mercury and the sprawling, still-forming organization that was being built to manage it stretched everyone to the limit. Soon after John Mayer put on the Space Task Group jersey, Carl Huss and Ted Skopinski followed suit, making Katherine the natural inheritor of the research report that would describe Project Mercury’s orbital flight. As had been the case many other times in her life, Katherine Goble was the right person in the right place at the right moment.
Sitting in the emptier office, she plunged into the analysis, although the pesky laws of physics turned an afternoon of rote celestial tennis practice into a forces free-for-all. Earth’s gravity exerted its force on the satellite and had to be accounted for in the trajectory’s system of equations. Earth’s oblateness—the fact that it was not perfectly spherical but slightly squat, like a mandarin orange—needed to be specified, as did the speed of the planet’s rotation. Even if the capsule were to shoot off into the air directly overhead and come back down in the same straight line, it would land in a different spot, because Earth had moved.
“In the recovery of an artificial earth satellite it is necessary to bring the satellite over a preselected point above the earth from which the reentry is to be initiated,” she wrote. Equation 3 described the satellite’s velocity. Equation 19 fixed the longitude position of the satellite at time T. Equation A3 accounted for errors in longitude. Equation A8 adjusted for Earth’s west-to-east rotation and oblation. She conferred with Ted Skopinski, consulted her textbooks, and did her own plotting. Over the months of 1959, the thirty-four-page end product took shape: twenty-two principal equations, nine error equations, two launch case studies, three reference texts (including Forest Ray Moulton’s 1914 book), two tables with sample calculations, and three pages of charts.
The rapidly growing Space Task Group was taking shape as an autonomous unit marching out in front of the space parade. The new endeavor consumed as many person-hours as it could be given. Even as the Space Task Group worked to create boundaries with the research center that had given birth to it, Space Task Group employees still had responsibilities to their old managers. Katherine’s and Ted Skopinski’s Azimuth Angle report was the work of the Flight Research Group, the responsibility of their branch chief, Henry Pearson, and while Ted Skopinski was increasingly out of sight, spending time over at the STG offices on the East Side, the report, still unfinished, was not out of Henry Pearson’s mind.
“Katherine should finish the report,” Skopinski said to Pearson. “She’s done most of the work anyway.” Henry Pearson had the reputation of being less than supportive of the advancement of female employees, but whether it was circumstance, the triumph of hard work over bias, or an incorrectly deserved reputation, it was on his watch that Katherine put the finishing touches on her first research report on the Friday after Thanksgiving 1959. “Determination of Azimuth Angle at Burnout for Placing a Satellite over a Selected Earth Position” went through ten months of editorial meetings, analysis, recommendations, and revisions before publication in September 1960—the first report to come out of Langley’s Aerospace Mechanics Division (or its predecessor, the Flight Research Division) by a female author. Stepped on, turned out, pulled apart, and subjected to every stress test the editorial committees could throw at it, Katherine’s road map would help lead NASA to the day when the balance of the space race was tipped in favor of the United States.
For Katherine, the report commemorated the beginning of a new phase not just at Langley but in her personal life. Somehow, during the long, bleary-eyed days of 1959, she accepted an offer even more enticing than being invited into the editorial meetings: Jim Johnson’s marriage proposal. The two married in August 1959 in a quiet ceremony at Carver Memorial. When she signed her first research report, she used a new name, the name that history would remember: Katherine G. Johnson.
CHAPTER NINETEEN
Model Behavior