Starman

Starmen are a strange breed of peaceful energy-based individuals.

Physiology
The Starmen seem to be a species made up of energy, as their "true form" is simply a ball of light. They are a peaceful race who find interest in exploring other worlds and observing other life forms.

When a Starman arrives on a world, they can use a simple strand of DNA to create an "environmental suit" by cloning a human body with which they can phsyically interact with other species.

Earth
Not much is known about the history of the Starmen. Whether they originated as energy beings or evolved into such through years of evolution is especially unclear. What is known, however, is that they have frequently explored Earth.

The launch of Voyager II unwittingly attracted on particular Starman to Earth. When his ship crashed, he travelled to a nearby house, and through a lock of hair cloned a body resembling that of a dead man named Scott Hayden. After sending a distress call, forced Scott's widow, Jenny to take him to Arizona where he could rendezvous with his ship.