 It's another day on the moon, paving the way for humankind taking its first steps on Mars. The journey has not been without its hiccups. First, Mission Control made the blunder of designating a landing zone for your spacecraft on the opposite side of a canyon from the unmanned cargo vessels carrying the necessary supplies to establish a base on the moon. You solved that problem by constructing your own bridge design out of the materials that were available to you. The mines back at Mission Control were not too happy with you rejecting their design, which they felt was sufficient for the job. You remind yourself that those same mines also thought getting a six on their university exams was sufficient for the job, and as a result, they are back on Earth pushing paper while you are well on your way to walking on Mars. But with one problem solved, you are faced with fixing their mistakes again. A second crew of astronauts has arrived and is orbiting the moon. Before descending to the moon's surface, they are supposed to deploy a communication satellite, dubbed the Leonardo da Vinci, to remain in orbit around the moon. But there seems to be a delay. The communication satellite makes use of the vectoring system Mark V, or VSV, in order to control the orientation of the satellite while in orbit. This control system requires an accurate calculation of the mass moments of inertia of the satellite. But one of the brilliant mines back on Earth that did this was sloppy and carrying units through all of their calculations, and now the mass moments of inertia are off by a factor that can only be described as being proportional to that engineer's IQ. You radio your colleagues in orbit to get a better sense of the problem. It seems that mission control has decided it was only fair to dish you out your own problem so that you wouldn't be jealous of all the fun we had designing and building our bridge down here. You give them way too much credit in their ability to plan anything. They have a team of 12 men trying to come up with a solution now, but all they have figured out is that their billion dollar communications satellite contains a control system that ironically cannot communicate with the outside world. So there is no means to solve this issue through a software update. Well, if my university years taught me anything, it's never to underestimate the capabilities of an intelligent and determined woman. So my money is on you solving the problem before they do. But try not to take too long, eh? We're looking forward to that resupply of totally approved beverages that you didn't happen to sneak on board your craft before leaving Earth. You think to yourself that if you can't update a software with real moments of inertia of the satellites, you might as well update the satellite with the moments of inertia that the software is expecting. By your calculations, you need to increase the moment of inertia of the satellite along its primary axis by 11.1 kilogram meters squared. And along its two transverse axis by 0.802 kilogram meters squared, all without changing the location of the center of mass of the satellite. You look around at what materials are available to you. There's a 3D printer on board that can fabricate just about any geometry you can think of out of titanium. To keep things simple, however, you opt for a simple design comprised of slender 2 centimeter diameter rods joined to form a T-shape that you can then join to the satellite to alter its mass distribution. You recognize that if you make the shape symmetrical, attach them to the satellite at its center of mass, and evenly distribute them angularly around the main axis of the satellite, you can alter the necessary moments of inertia without moving its center of mass. Mission control reluctantly approves your plan, but it's concerned that if you add too much mass to the satellite, it will adversely affect the lifetime of the satellite. You try not to roll your eyes as you explain to them that you understand that adding mass to the satellite won't mean it will burn through its truss or feel faster than intended, and you intend to optimize the design concept for minimum mass. You switch off the radio just as one of the mission control scientists start talking about constitutive equations and material deformation. You realize they are beginning to overanalyze a problem to try and save face, but you know this problem can adequately be analyzed by treating the satellite and the 3D printed structures as rigid bodies. Time to crunch some numbers.