Scientific events 1945 1968

1. Discovery of the structure of DNA molecule (1953)
In 1953 british molecular biologist Francis Crick with James Watson discovered the structure of DNA molecule.
Crick and Watson showed off the first model of DNA in 1951, which was unfortunately wrong. Two years later
in 1953 they finally figured out how the structure of DNA looks and they published it in Nature on 25. 4. 1953.
The Crick’s letter to his son which explained their discovery was sold for $6,059,750 in auction at Christine’s
New York on 10. 4. 2013.
First accurate atomic clock (1955)
In 1955 Louis Essen invented the first accurate atomic clock. It was cesium standard atomic clock based on
transition of caesium-133 atom. Louis Essen built it with Jack Perry at the National Physical Laboratory in the
United Kingdom. Calibration of the caesium standard atomic clock was carried out by the use of the
astronomical time scale. The Cesium standard is being used until now, for example in GPS satellites.

2. Sputnik 1 (1957)
Sputnik 1 was the firstartificial Earth satellite.Itwas constructed by Russian rocket scientist Sergei Korolev and
launched from Baikonur Cosmodrome in former Soviet Union on 4 October 1957. Sputnik has only one
scientific device – transmitter. The average of this satellite was only 58 centimetres and the weight 84
kilogrammes. Sputnik 1 burnt up on 4 January 1958, after travelling about 70 million kilometres and spending
three months in orbit.
First flight to the space (1961)
On 12 April 1961 Russian astronautYuri Gagarin travelled as a first human to the space. He flew with the space
shift called Vostok 1. It was made for one person and the weight was five tunes. The duration of the flight
around whole Earth was one hour and 48 minutes. The flight was about 200 kilometres above the Earth. He
returned without injuries after he catapulted himself 7 kilometres above the Earth.

3. Vine–Matthews–Morley hypothesis (1963)
In 1962 Harry Hess published the sea-floor spreading hypothesis. According to him, seafloor was created at
mid-oceanic ridges by the convection of the earth's mantle and pushing the old crust away. Geophysicist
Frederick John Vine and the Canadian geologist Lawrence W. Morley independently realized that it wasn’t
alright. In 1963 Drummond Hoyle Mathews joined them and together they published their own hypothesis. It
was based on the Hess’ hypothesis with some additions about geomagnetism – it basically proved that the sea
floor spreads by measuring flips in the magnetic orientation of the sea floor samples they took.
Pulsar (1967)
Pulsar is a short name for pulsating radio star. It is highly magnetized, rotating neutron star that emits a beam
of electromagnetic radiation. The effort of radiation regularly change. It calls May effect. These pulsar stars
were explored by scientists Jocelyn Bell Burnell and Antony Hewish from Cambridge University. They said that
was the new type of a star that is shine only one year.
Jaroslav Heyrovský’s Nobel prize (1959)
Jaroslav Heyrovský was a Czech chemist and inventor. He invented polarographic method for which he was
awarded with the Nobel prize on 10. 12. 1959. Ne was nominated 18 times, 14 times in chemistry, once in

4. physics and three times in physiology or medicine. He was also awarded the State Prizeand First Grade in 1951
and in 1955 the Order of the Czechoslovak Republic. On the moon is crater named Heyrovský in his honour.