Star jelly is a gelatinous substance, which, according to folklore, is deposited on the earth during meteor shower

Meteor shower

A meteor shower is a celestial event in which a number of meteors are observed to radiate from one point in the night sky. These meteors are caused by streams of cosmic debris called meteoroids entering Earth's atmosphere at extremely high speeds on parallel trajectories. Most meteors are smaller...

s. It is described as a translucent or grayish white gelatin which tends to evaporate shortly after having fallen. Explanations have ranged from the material being the remains of frogs and toads, or of worms, to the byproducts of cyanobacteria, to paranormal

Paranormal

Paranormal is a general term that designates experiences that lie outside "the range of normal experience or scientific explanation" or that indicates phenomena understood to be outside of science's current ability to explain or measure...

 origins.