Worked for the secret X-30 National Aerospeace Plane Program for 5 years at WPAFB. This was our plane supposedly to go Mach 25. Have a few stories of my own.
Maybe that’s what we had on shuttle downlinks, if it could reach shuttle orbits. I know the AF got worked up about one particular downlink shuttle tape and took all copies. I figure since this was a long time ago and with the release of the fighter jet tapes showing similar “objects” they aren’t as worried about it. It’s either declass on one thing or another coming.
Oh, just read that it was cancelled before a prototype was made. Yeah, so that rules it out unless it was not really “cancelled.” Other projects may exist. NASA folks I’ve worked with, know and are related to... suspect these objects aren’t man made (they look just like what was seen on the fighter jet tapes... but flying near the shuttle in the 90’s). But DARPA and its contractors can create some pretty amazing things that could easily appear unusual.