Spicule
From Glossary of Meteorology
spicule
- A spike of ice formed during the freezing of a water drop or a contained volume of water (as in a puddle or freezer container); expansion of the inward freezing ice expels any remaining water through a weak point in the shell which then freezes as a spike in the colder environment.
Spicules are several hundred kilometers in diameter and extend outward 5000–10 000 km. Observed in photographs of the limb, these features have a lifetime of several minutes.