Vegan (Have Space Suit—Will Travel)

Vegans are an advanced race from the Vega System.

Biology
The Vegans are able to communicate with Humans by a form of telepathy: their language has been described as sounding like a birdsong, and only the intended listeners will understand the meaning of what the Vegan is saying.

Vegans have a pouch in their bodies, much like Earth marsupials. They can also go through freezing without suffering any cellular damage. While they breathe oxygen, they prefer an atmosphere with a higher concentration of ozone than Earth's, due to their homeworld having an ozone-rich atmosphere. Being native to the Vega System also makes them highly resistant to the ultraviolet radiation emitted by their home sun.

Culture and society
Their ships seem to operate on wormholes, and their mathematics use base 5. They're one of the member races of the Three Galaxies.

History
A Vegan, which the earthlings call "Mother Thing", is captured along with the daughter of an Earth scientist and rescues the earthlings from an alien kidnapper. The Vegans take the earthlings to their home planet, Vega 5, heal their injuries, and take evidence to an intergalactic tribunal which punishes the kidnappers, before returning the children to Earth.

Appearances

 * Have Spacesuit – Will Travel, by Robert A. Heinlein (1958)