Topic summary
Mira variable star

Extracted from the Wikipedia article Mira variable.
Early models of Mira stars assumed that the star remained spherically symmetric during this process (largely to keep the computer modelling simple, rather than for physical reasons). A recent survey of Mira variable stars found that 75% of the Mira stars which could be resolved using the IOTA telescope are not spherically symmetric, a result which is consistent with previous images of individual Mira stars, so there is now pressure to do realistic three-dimensional modelling of Mira stars on supercomputers.