Venus has been visited by numerous unmanned missions but has not been visited by any manned missions due to its extreme surface conditions. The first successful mission to Venus was the Soviet Union's Venera program, which included several probes that landed on Venus's surface and transmitted data back to Earth. Following this, there have been several other missions, like NASA's Magellan orbiter, which mapped the surface of Venus, and ESA's Venus Express, which studied its atmosphere. The extreme conditions on Venus – high temperatures, crushing atmospheric pressure, and corrosive atmosphere – make manned missions to Venus exceedingly challenging and currently beyond our technological capabilities.