Albereo (spelled Albireo by some) is one of the most beautiful double stars in the visible universe. It is made up of a small blue star and a large golden yellow star. Since they sparkle like brilliant jewels when viewed through a telescope, astronomers refer to their color as sapphire and topaz.
From a distance, a binary star looks like a single star but really it is two stars, paired up for billions and billions of years, locked in a gravitational embrace from which they never waver. The two stars are often of different mass and size, but still they remain joined in perfect equilibrium. You might be amazed to know that most stars in the universe are binary.
Stars grow bigger and hotter as they grow old, and the eventual death of a star is not a quiet passing—some stars expire with a massive supernova explosion. Each star in a binary pair evolves in this way, but they do so at different rates. When one star grows so big that its mass begins to endanger the life of its companion, it transfers its mass to the smaller star. The death-explosion of the larger star is delayed, often for millions or billions of years. By giving part of itself to the other, the larger star lengthens the lives of both. It is a demonstration of a beautiful truth of kindness: when one shares unselfishly, all will benefit—even eventually the one who gave.