**Venus may be the closest thing Earth has to a planetary twin. So how did it become so different?** Earth and Venus are rocky worlds of similar size, formed in the same solar system roughly 4.5 billion years ago. But today, the resemblance ends there. Venus is an extreme world with a massive atmosphere, crushing pressure, scorching temperatures and clouds containing sulfuric acid. Yet scientists think this hostile planet may once have been far more Earth-like. So what happened? In **Breakthrough: Voyage to Venus**, scientists look to our neighboring planet for answers—not only about Venus, but about the forces that determine how rocky planets evolve. NASA's upcoming missions will investigate Venus from above and within its atmosphere. DAVINCI is designed to descend through the planet's thick atmosphere, measuring its chemistry and capturing images as it heads toward the surface—all while experiencing dramatic changes in temperature and pressure. The goal is to help answer one o...