As is known to us all, the first human Moon landing (happen) more than 50 years ago. But do you know that before human astronauts (send) to the Moon, some other creatures had travelled in space and circled the Moon? That honour goes to two Russian tortoises and several smaller creatures went along for the ride.
On 14 September 1968. the Soviet space program sent two tortoises along some other small creatures into space for trip around the Moon. NASA calls it“ the first successful circumlunar(环月的)mission (carry) out by any nation". After the travel, the tortoises (eventual) returned to Moscow on 7 October. Both tortoises survived the trip but not the later experiment. On 11 October 1968, the animals were dissected(解剖) (see) how their bodies were affected by the space travel. The dissection showed that "the main (structure) changes in the tortoises were caused by a lack of food rather than the space travel". The tortoises had lost about 10 percent of their body (weigh), but they had stayed active and shown no loss of appetite(胃口).
