The three-year-old tortoiseshell has her own Facebook page and a YouTube video that's been viewed over a million times, and appeared on the Today Show last week. (Watch National Geographic cat videos.)

One look at this cat and you can understand why: One half is solid black with a green eye—the other half has typical orange tabby stripes and a blue eye.

How does a cat end up looking like that? Leslie Lyons, a professor at the University of California, Davis, who studies the genetics of domestic cats said she's never seen a cat exactly like Venus.

"She is extremely, extremely rare," Lyons said. "But you can explain it and you can understand it."

(See "House Cat Origin Traced to Middle Eastern Wildcat Ancestor.")

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