1. The dogs were named Belka (squirrel) and Strelka (little arrow) and flew aboard Sputnik 5, which also had two rats and 40 mice on board.

2. Three weeks earlier, two dogs, Bars (panther) and Lisichka (little fox), had been killed when a booster rocket on a test flight blew up on take-off.

3. The first dog to orbit the Earth was Laika in 1957. She was monitored during the flight but no plans were made to bring her back.

4. A monument to Laika was erected near Moscow 40 years after her death.

5. A year after Strelka returned, she gave birth to six puppies, one of which was given by Soviet premier Khrushchev to JF Kennedy’s daughter.

6. Michael Hutchence starred in an Australian film called Dogs In Space in 1986.

7. It had nothing to do with space dogs but was about a pop group called Dogs In Space.

8. Even before Laika, the Russians had sent dogs on sub-orbital flights to space since 1951.

9. They chose female stray mongrels for their temperament and ability to cope with stress.

10. Two dogs were in orbit for 22 days in 1966. It took five years for humans to surpass that mark.