This one has been bugging me for years

I’ve watched this video I’ve seen people talk about it and make theories about it but I got nothing

Here’s all I remember

The start was a black screen with text saying something similar to

“In (some year) a tape was found on a little planet called earth the following footage you’re about to see has nothing to do with that tape”

It then cut to what appearers to be a children’s cartoon but it quickly turns into static with screaming and distorted colors and the music ramps up before ending.

I think the title was something like antamon contency.

The theory I watched about it mentioned whatever the first word of the title was shared a name with a comet that passes by earth or something similar.

Any idea what this video could have been?