As the brightest star in the constellation Cassiopeia the Queen, Alpha Cassiopeiae doesn’t have any fantastic stories behind it. That is, other than helping to define one of the most familiar asterisms in the northern sky. Depending on your perspective, this star marks either the righthand vertex of the “W“ pattern, or the lefthand vertex of the “M.”
From mid-northern latitudes, the star, like the rest of Cassiopeia, is circumpolar, meaning that it never dips below the horizon.
The star’s name, Schedar, derives from the Arabic word for “breast.” Other stars in the constellation are named for the queen’s hand and foot. The middle star of Cassiopeia’s W (or M) is sometimes called Navi, but that’s an unofficial designation that has nothing to do with anatomy. Astronaut Virgil Ivan “Gus” Grissom invented the moniker because he decided to name navigation stars after himself and his two Apollo 1 colleagues. (The others being “Regor” and “Dnoces.”)
Schedar lies about 230 light-years away and shines steadily at magnitude 2.2. Despite skywatchers a couple of centuries ago suggesting that the star varied in brightness, modern astronomers have discerned no fluctuations.
The star is about five times the mass of our sun. The extra heft makes Schedar burn brighter and faster than smaller stars. It’s perhaps only 200 million years old (our sun is 5 billion years old). Eventually, after it has used up its hydrogen fuel, Schedar will become a red giant star, throw off its outer layers, and leave behind a white dwarf.
Schedar also has three stellar companions, all of which are too close to the star to be easily seen.