Astronomy
The Structure and Lifetime of Sunspots
Quick fact
A single sunspot can last anywhere from a few days to a few months, and its structure includes a dark central zone called the umbra and a lighter surrounding region called the penumbra.
Why this is interesting
Have you ever seen a dark spot on the Sun? These sunspots can be larger than Earth, yet they are just the tip of the iceberg of a magnetic storm happening on our Sun.