Venus has been, as the New York Times puts it, "overlooked" by NASA for decades—but no longer. The space agency on Wednesday announced two missions to Earth's closest planetary neighbor slated for the late 2020s. Veritas will map the planet's surface, while DaVinci Plus will analyze the Venusian atmosphere to determine whether it was once habitable. The AP reports that will mark the first US-led mission to the planet's atmosphere since 1978. In 1989, Voyager 2 passed by Venus and its moons, and in 1990, NASA sent its last dedicated spacecraft, Magellan, to study Venus. Since then, Mars has dominated—and a lot about Venus remains unknown.
NPR reports that Venus is sometimes called Earth's "evil twin." The two planets are similar in size, mass, and composition, but Venus is 900 degrees Fahrenheit at its surface—the hottest planet in our solar system—and has a thick, cloudy atmosphere of carbon dioxide that is toxic to humans. Some scientists wonder if it was once even more similar to Earth, perhaps with its own oceans, until something went wrong—perhaps some sort of "runaway greenhouse effect." Scientific American says some in the scientific community refer to the "Venus curse" when talking about those who wished Venus was more studied, but, much like the Boston Red Sox who for decades failed to win a World Series, feared it might not ever happen. (The full SA story is worth a read.)