# A Menu Bar App Tracks the ISS Urine Tank in Real Time
*Event date: 2024-12-24*
Some software projects are useful because they solve a common problem. Others are memorable because they solve a very unusual one. pISSStream falls squarely into the second category. The GitHub project is a menu bar app that shows how full the International Space Station’s urine tank is in real time, and it is available across macOS, iOS, watchOS and visionOS.
The title alone makes the project hard to ignore, but the underlying idea is straightforward enough. Space stations generate telemetry, and software can turn telemetry into something legible for people on the outside. In this case, the data point is unusually specific, almost absurdly so: the fullness of the station’s urine tank. That specificity is exactly what makes the app interesting as a piece of software design.
On one level, the app is a novelty. It is the sort of project that gets attention because it is funny to say out loud and because it occupies a very narrow slice of the world’s infrastructure. But the novelty sits on top of a real engineering habit: take a live data source and surface it in a place where it can be seen quickly, without forcing the user to dig through dashboards or logs.
The fact that the app spans several Apple platforms also matters. A small telemetry display can be more than a one-off desktop curiosity when it moves from the menu bar to the watch and to other device types. That makes the project feel less like a joke and more like a demonstration of how niche monitoring tools can be adapted to multiple form factors once the underlying data flow is in place.
There is also a deeper software lesson here about what counts as a useful interface. Many people think of interfaces as ways to simplify familiar tasks, but this project shows a different angle: an interface can make hidden operations visible. The ISS urine tank is not something most people will ever need to monitor, and that is precisely why the app sticks in the mind. It reveals the sort of practical, unglamorous system detail that spacecraft depend on but ordinary users never see.
That is probably why projects like this travel well online. They are funny, but not empty. They are specific, but not trivial. A menu bar app for the ISS urine tank is the kind of idea that reminds people that software can be playful without being unserious. It can also reveal the infrastructure underneath a system in a way that makes that infrastructure harder to ignore.
