Venus' newly found rift valley is 3 miles deep and 175 miles wide. Pioneer radar mapper measurements found the canyon to be at least 900 miles long with no apparent beginning or end. This geologic feature is deeper than anything on earth and appears larger than Valles Marineris on Mars, previously the solar system's largest canyon.
The Russian Venera spacecraft found continuous lightning activity from an altitude of 32 km down to about 2 km, with discharges as frequent as an amazing 26 per second. The Pioneer Orbiter also observed this lightning, measuring such discharges during every pass across the planet's night hemisphere.