Viking 1
Viking 1 was the first of two spacecraft (along with "Viking 2") sent to Mars as part of NASA's Viking program. On July 20, 1976, it became the second spacecraft to soft-land on Mars, and the first soft lander to successfully perform its mission. (The first spacecraft to soft-land on Mars was the Soviet Union's Mars 3 on December 2, 1971, which stopped transmitting after 14.5 seconds.) "Viking 1" held the record for the longest Mars surface mission of days (over 6¼ years) or Martian solar days, until that record was broken by "Opportunity" on May 19, 2010.
Sleepers of Mars
While on the planet in the previous story, the Soviet and British crews had explored part of Mars around their landing sites, discovering vegetation plant life, in the form of scrubby bushes growing along the banks of ancient canal works, with sluggish water still in them. The planet also hosted AI robots, hostile to the visitors from Earth. They seemed almost wild, feral machines living without control of organic life. Due to fatal encounters with these robots, and ill planned gunfight with the British crew, the Soviets now number four crewmen. Preparing to depart for Earth they discuss the fate of their mission - originally a race between the nations of Earth to be the first to reach Mars. The British and the "Gloria Mundi" had won the race, reach Mars before the Soviets and United States (whose rocket had crashed with no survivors upon reaching Mars). The Russians speculate what would be the global reaction if the "Gloria Mundi" reaches Earth, and then the Soviets return, and claim that they were the first to land on Mars, not the British. They conclude that they would not be believed. However, they reason that if they succeed in racing the British home, then they can claim that the USSR was the first to conquer the Red Planet, and the British will be disbelieved.