Mira variables

Mira variables are a type of pulsating star known for their dramatic changes in brightness over time. These stars are typically red giants, large and cool, and their brightness cycles can last about 80 to 1,000 days. During these cycles, they expand and contract, causing their brightness to increase and decrease significantly—sometimes by a factor of 100. The name "Mira" comes from the first star of this type discovered, which appears to flicker in the night sky. These stars are important for understanding stellar evolution and help astronomers study how stars change over their lifetimes.