Right. We won't necessarily need a separate sensor for each of them, but we do need to select which ones we want to use and how they fit into the reporting system. Most things that use atmospheric sensors are for much larger volumes than a cube-sat. Pressure and temperature should be easy, but humidity and composition might take more work. Humidity detectors are often tied to de-humidifiers, etc, so there might be some hacking or custom design involved. If we want exact air comp, we might need a sensor for each gas we want to detect. Its possible there's some sort of all-in-one controller out there for this sort of thing, but most of the ones I've found are too big.
