This strange substance has been recorded as far back as the 1300s.
A meteor blazing across the daytime sky is certainly an unusual event. Historically it was - and often still is - seen as a portent, a sign of something powerful and unknowable. Strange things were said to happen around these events, with one of the strangest being the appearance of "star jelly" in fields and other open areas. And it has appeared again, observed in the Ham Wall park in England not long after the amazing Russian meteor strike happened.
Star jelly is usually found as a viscous substance, gelatinous, possibly sticky or slimy. It might be transparent, white, or a pale shade of blue or green. One of the earliest descriptions of star jelly was by John of Gaddesden (1280-1361) who called it stella terrae, described it as a "mucilaginous substance lying upon the earth," and wondered whether it might have medical applications.
Many possible explanations for the phenomena have been proposed. No doubt each of them has been the culprit at least once. This doesn't seem like the sort of thing that will have one specific answer.
One of the more common explanations is that it is a slime mold. This fascinating phenomena is rarely seen in the wild, which may be why people who come upon it are frightened and confused. As well they might be.
Slime mold can take a variety of shapes and forms, and is basically a fungus that acts like an amoeba. Slime mold moves along the ground with great purpose (albeit slowly). If it is divided, its separated parts will crawl back to each other to reunite. It follows chemical signatures to track its prey. Slime molds can appear quite suddenly, especially after a rain or damp night. They vanish almost as quickly, turning to dust and dispersing with the winds.
In the case of the recent sighting of star jelly in an English nature reserve, officials say it is most likely abandoned and unfertilized frog spawn. It seems that this is the amphibian mating season in England, and a startled female frog will drop her spawn (unfertilized eggs suspended in a protein gel) in an attempt to get away from a predator.
However, the park officials also note that an unusual bright light was seen over the park just a week before the appearance of this strange jelly. Some have called it a UFO, although the park officials describe it as a "meteor-like object" which was photographed by a wildlife photographer.