STScI Preprint #1208
There are three classes of stars like the Sun that are defined by Cayrel de Strobel (1996): Solar-type (or Solarlike) Stars, Solar Analogous Stars, and Solar Twins. The defining physical properties of any star are its mass, composition, and age, yet none of these is a fully or directly observable quantity. Also, angular momentum and companionship are important influences on the behavior of stars like the Sun and cannot be ignored.
We will review some of the observational limits on these fundamental properties and discuss how recent observations allow samples of solar-type stars to be defined and tabulated. Some of the questions raised are:
- What is a solar analog? What is a solar twin? Who cares?
- The Sun as a star: how would we judge it from afar?
- How well can we measure basic stellar properties relative to solar?
- Are the spectroscopic micro-differences we see significant, or just variations within a common envelope?
- Is angular momentum a big deal or small potatoes?
- Do we understand the basic physics of stellar evolution?
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