nosambos, very interesting and curious images.

Did you ever get a scientific explanation? That's incredible!

I've never questioned why icicles develop horizontal ridges before! That's fascinating, it will be bugging me until I figure it out.

I do, however, know exactly what happened with your bizarre-looking icicle hanging from the rain gutter.

Originally the water was dripping down the painted aluminum surface of the rain gutter, and it froze. Then the sun warmed up metal up and it caused the ice to detach from the metal and hang freely.

...just noticed that you said it's not a remnant of the icicle when attacked to the gutter.

I still think it is the best explanation. Water dripping off of the roof is going to cling to the metal's surface at first, but once some freezes, it will follow the lowest part of the ice, which is the OUTSIDE of the icicle.

Meanwhile melting is going to be generated by the radiative warmth of the metal when sun is on it, melting it from the "inside."

That will cause the ice formation to gradually migrate outward as more ice freezes from the outside and thaws from the inside.

You can see where this process of outward-migrating ice began, at first, while the icicle was still attached to the metal. The lower portion, where the metal was shaded from sunlight because the surface faces downward, was still attached.

Then, the whole thing detached and swung back a little.

You can also see where the water that was following the contours of the metal hit the crack where two sections of rain gutter were joined together, and started to drip straight down off of the metal, forming a regular icicle at the end.

The tip was originally pointing straight down. When the whole thing detached and swung back, the downward-pointing tip started to point outward. The fact that you can tell the tip would be exactly vertical if you pushed the icicle back where it originally was against the gutter, is, I think, pretty solid evidence that it was once attached.

Sorry, I just really enjoy natural "mysteries" like this.

This explanation is interesting.

Pizzuti, I agree with your "was attached" theory.