As computers have become more advanced, faster, and more capable, the arguments in favor of manned spaceflight have become weaker, and space travel has increasingly become the domain of machines. Long before the invention of the microchip, Isaac Asimov proposed exactly this, describing unmanned, computer-controlled space exploration vehicles that would be able to venture into territories too extreme and too dangerous for humans. That vision has come to pass, and it is now commonly argued that humans are indeed too soft, vulnerable, and unreliable to utilize in spaceflight, and that removing them from the paradigm removes the weakest link. Manned spaceflight has largely been relegated to an oft-maligned holdover of Cold War international competition and patriotism. This is a mistake.
As a bit of a side project at work recently, I did some modeling work on TESS, which is a NASA spacecraft that was launched to help search for exoplanets using the transit method (I know, you could never have guessed that from the name's acronym breakdown). Working with satellites as much as I do, this was a really interesting project, because it was quite distinctive in its orbit and mission architecture from most spacecraft that I get to study on a regular basis. For one thing, it is a remarkably low-cost, robust, straightforward system, quite different from what you often see with NASA programs, which because of their scientific goals are often pushing the very edge of our capabilities and therefore become very complex and very expensive. For another, it utilizes a simply fascinating orbit. Since I've been trying to post occasional in-depth articles on various academic topics, it seemed appropriate to share some of what I learned from that project here.