Gandalf’s painful encounter with a ceiling beam in Bilbo’s hobbit-hole was not in the script. Ian McKellen banged his forehead against the beam accidentally, not on purpose. But Peter Jackson thought McKellen did a great job “acting through” the mistake, and so kept it in.
From the Cat’s Eye to the Eskimo, planetary nebulae are arguably among the most dazzling objects in the Universe. These misnamed stellar remnants are created when the outer layers of a dying star blows off and expands into space. However, they can look radically different from one another, revealing complicated histories and structures.
But recently, astronomers have argued that some of the most exotic shapes are the result of not one, but two stars at the center. It is the interaction between the progenitor star and a binary companion that shapes the resulting planetary nebula.
The archetypal planetary nebula is spherical. Most planetary nebulae, however, have been shown to be non-spherical, complex structures.