Nicknamed Earth’s evil twin, Venus seems like everything our planet is not: scorching hot, dried out and covered in toxic clouds.

But a mere one or two billion years ago, these two wayward siblings might have been more alike. New computer simulations suggest that early Venus might have looked a lot like our home planet – and it might even have been habitable.

“It’s one of the big mysteries about Venus. How did it get so different from Earth when it seems likely to have started so similarly?” says David Grinspoon at the Planetary Science Institute in Tucson, Arizona. “The question becomes richer when you consider astrobiology, the possibility that Venus and Earth were very similar during the time of the origin of life on Earth.”

Grinspoon and his colleagues aren’t the first to imagine that Venus was once hospitable. It’s similar to Earth in size and density, and the fact that the two planets formed so close together suggests that they’re made of the same bulk materials. Venus also has an unusually high ratio of deuterium to hydrogen atoms, a sign that it once housed a substantial amount of water, mysteriously lost over time.

Missed this one.  To read more, click here.