Stars are the building blocks of galaxies. Astoundingly, there are 4,000 million stars in our own Milky Way, and there are two million million galaxies in our visible universe. Stars are simply luminous spheres of plasma held together by gravity, but their age, location and composition are the ciphers that can explain the evolution and dynamics of the galaxy within which they exist. Forty Ways to Know a Star offers forty distinct ways of encountering, explaining and knowing a star. You might know it by its birth, by its death, by its galaxy, from a distance, from its matter, or up close and personal. Each meeting is illuminated by bespoke illustrations, and they combine to create a broader canvas of the many forms and incarnations that stars take. Elegant writing turns the complexity of the physics into irresistible storytelling, and beautiful photographic imagery of the heavens is scattered throughout.