With the advent of the Soviet space program, this tradition has spread into space, where appropriately small packages of bread and salt are used nowadays.[1][2] It was observed at the Apollo–Soyuz Test Project and the Salyut programme, when crackers and salt tablets were used in the spaceship. Bread chunks and salt were used as a welcome at the Mir space station,[2][3] a tradition that was extended on the International Space Station.[3][14] Bread and salt are also used to welcome cosmonauts returning to Earth.[4]