Did you know there's a set of planetary "twins" in our solar system, and that one of them is considered "evil" of sorts?
Venus is known as "Earth's twin" because both planets are nearly the same size, have about the same mass and are made out of the same materials. They also formed in the same inner part of the solar system.
From that, you would think that Venus and Earth are very much alike. But as NASA astronomers have pointed out, somewhere along the way, billions of years ago, they went two very different paths.
"Some people like to say Venus went bad or something went wrong. I like to say that somewhere along the way, something good happened on Earth," Dr. Lori Glaze, NASA Director of Planetary Science, explained in a video.
Venus is the second planet from the sun, Earth's closest neighbor at 38 million miles away, and the sixth largest planet. It's also the hottest planet in the solar system -- like, hellishly hot.
"In fact, it's so hot on Venus that you can melt lead. The temperatures on the surface of Venus are over 900 degrees Fahrenheit," said Dr. Glaze. "And then Venus is covered in a 15-mile-thick layer of clouds, and those clouds are made of sulfuric acid. So it is a crazy place."
So, how could two planets, roughly the same size, formed around the same time from the same materials be so different today?
"Venus spins backward, has a day longer than its year, and lacks any semblance of seasons. It might once have been a habitable ocean world, like Earth, but that was at least a billion years ago. A runaway greenhouse effect turned all surface water into vapor, which then leaked slowly into space," NASA explained. "The present-day surface of volcanic rock is blasted by high temperatures and pressures. Asked if the surface of Venus is likely to be life-bearing today, we can give a quick answer: a hard 'no.'"
Scientists with NASA and the European Space Agency have teamed up in an effort to learn more about how Venus formed, how it evolved, and why it's so different from Earth.
"Venus may hold lessons about what it takes for life to get its start – on Earth, in our solar system, or across the galaxy," NASA said. "By studying why our neighbor world went in such a different direction with regard to habitability, we could find out what could make other worlds right."