Interesting

[guohua]

Yes it looks like a TR-3 I think.

Like a Hypersonic Missile': Enigmatic Black Triangular Object Spotted in California Skies

While the blogger mused about the alleged extraterrestrial nature of the phenomenon in question, some social media users suggested that it could've been a balloon.

A peculiar phenomenon was spotted in the skies above Pasadena last month, with blogger and UFO hunter extraordinaire Scott C. Waring suggesting a possible extraterrestrial craft sighting.
The phenomenon in question, as depicted in a YouTube video (the veracity of which couldn't be immediately confirmed) uploaded by Waring, appears to be a black, vaguely triangular shape.
The blogger also pointed out how the object appeared to be rotating, and further alleged that it looked like "the hypersonic missile that the USAF has created, except this was hovering and moving very slowly".


Source

They think this is a Balloon!