Actually, most of the recent reports are outside of the states, so certainly not just Hughesnet, there are still various outages in the states. All DownDetector is, is a tool that scours the internet for potential outages, not everyone is going to report immediately to a website that downdetector looks for in terms of issues.
Facebook accessibility has been an issue with Hughes as of late(Notably Spaceway3), but this time, it appears to be impacting Jupiter, and OTHER internet providers as well, which is a sign that someone somewhere in the middle could be having routing issues.
Think about this boudman, how many people on Twitter will post @Facebook instead of @TheirISP when they have problems? Not many, as they assume it's just an ISP issue. That is where downdetector gets most of their data from, is Twitter.
I don't really see how downdetector is relevant at all. From my house, on the same computer, I can access facebook (minimally) using a proxy server. If Facebook were actually the cause of this, the internet would be exploding. Not to mention the apparently ongoing issues Hughesnet has with Facebook. Ergo: Hughesnet, PLEASE get it together.