Short answers, pulled from the story.
Venera 9 was a Soviet uncrewed mission to Venus, launched on the 8th of June, 1975, with a total mass of 4,936 kilograms. It consisted of an orbiter and a lander. The lander touched down on Venus on the 22nd of October, 1975, returning the first photograph ever taken from the surface of another planet.
Venera 9 sent back black-and-white television pictures of a rocky slope near Beta Regio, showing rocks between 30 and 40 centimeters across that showed no signs of erosion. No shadows were visible in the images and no dust appeared to drift in the air. The lander measured a light level of 14,000 lux, comparable to Earth in full daylight, despite no direct sunlight reaching the surface.
The Venera 9 lander operated for exactly 53 minutes after touchdown before the orbiter passed out of radio range and contact was lost. Survival was extended through pre-cooling before atmospheric entry and a circulating fluid system that distributed heat during surface operations.
Venera 9 detected hydrochloric acid, hydrofluoric acid, bromine, and iodine in Venus's atmosphere. Surface pressure measured about 90 atmospheres and surface temperature reached 905 degrees Fahrenheit. Cloud layers were 30-40 kilometers thick with bases at 30-35 kilometers altitude.
The Venera 9 orbiter became the first spacecraft ever to orbit Venus, entering orbit on the 20th of October, 1975. It completed 17 survey missions between the 26th of October and the 25th of December, 1975, studying cloud layers and atmospheric parameters.
One of the two camera lens covers on the Venera 9 lander failed to open, limiting photographs to a 180-degree arc instead of the planned full panorama. The same failure recurred with Venera 10, which landed about 2,200 kilometers from the Venera 9 site.