Melba Roy, NASA Mathmetician, at the Goddard Space Flight Center in Maryland in 1964. Ms. Roy, a 1950 graduate of Howard University, led a group of NASA mathmeticians known as “computers” who tracked the Echo satellites. The first time I shared Ms. Roy on VBG, my friend Chanda Prescod-Weinstein, a former postdoc in astrophysics at NASA, helpfully explained what Ms. Roy did in the comment section. I am sharing Chanda’s comment again here: “By the way, since I am a physicist, I might as well explain a little bit about what she did: when we launch satellites into orbit, there are a lot of things to keep track of. We have to ensure that gravitational pull from other bodies, such as other satellites, the moon, etc. don’t perturb and destabilize the orbit. These are extremely hard calculations to do even today, even with a machine-computer. So, what she did was extremely intense, difficult work. The goal of the work, in addition to ensuring satellites remained in a stable orbit, was to know where everything was at all times. So they had to be able to calculate with a high level of accuracy. Anyway, that’s the story behind orbital element timetables”. Photo: NASA/Corbis.