Watching NASA's 720p stream after being accustomed to SpaceX's

720p stream the hher resolution you want to stream in, the more it will demand in bitrate (how much data you upload per second) and your encoding. for example, if you use CPU encoding. Answering your question. You can use resolution 1664x936, 1536x864, 1280x720. All this allows you to save bitrate, the quality will be better. Please note that image clarity

720pstream, 720p: Less demanding on your computer's processing power for encoding the stream. 1080p: Requires more processing power for encoding the stream.