President vowed to send a man to the moon by the end of the 1960s

The correct answer is "John F. Kennedy".

The Cold War was a prolonged period of the tense political relationship between The Soviet Union and the United States. It started with the end of the Second World war in 1945 and ended with the dissolution of the Soviet Union in 1991. During this period of time, there were many "competitions" between these 2 powers at political, military and scientifical level.

The Space Race was one of them. The Soviet Union would defeat the US in putting the first man on space (Yuri Gagarin) in 1961. This prompted a massive investment from the US government in order to secure the next checkpoint which would be the landing on the moon.

The objective would be achieved during John F. Kennedy's presidency with the landing of the Apollo 11 on the moon. Neil Armstrong was the first man to set foot on it on July 20th, 1969.

they have different colored collars

radioactive dating, also known as  radioisotope dating  is a process that in  estimating the approximate  age  of  rocks. these data can be analyzed from  the studies dealing with the  decay of the radioactive elements that are present in these rocks. in nature, there are a few types of materials or atoms which are quite unstable and they spontaneously decay or breakdown to form other kinds of atoms.