Mira Stars Much Smaller Than Previously Believed, page 1

According to a recent study to be published in the journal Astronomy & Astrophysics, Mira stars are only half the previously estimated size.

Miras are a class of stars that contains variable red giants and are about the size of the Sun. Astronomers consider Mira stars especially interesting as they're currently experiencing the very fate of the Sun in about 5 billion years.

REDNOVA
An international team of astronomers led by Guy Perrin from the Paris Observatory/LESIA (Meudon, France) and Stephen Ridgway from the National Optical Astronomy Observatory (Tucson, Arizona, USA) has used interferometric techniques to observe the close environments of five Mira stars, and were surprised to find that the stars are surrounded by a nearly transparent shell of water vapor, and possibly carbon monoxide and other molecules.

This shell gives the stars a deceptively large apparent size. By penetrating through this layer using the combined light of several telescopes, the team found that Mira stars are likely only half as large as formerly believed.

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