Sputnik, the first artificial satellite

By Théo Pirard

Between July 1957 and December 1958 the worldwide scientific community marked the IGY, or International Geophysical Year. Both Moscow and Washington made known their intentions to send scientific instruments around the Earth. The USSR (The Union of Soviet Socialist Republics) banked on a 1,3 ton geophysics observatory which would finally be launched on the 15th of May 1958 under the name of Sputnik-3. The authorities had given the project the green light in January 1956. But the programme encountered a number of delays. Out of fear of losing out on a ‘first’ in terms of the space race the Soviet government accepted, in February 1957, the PS plans (PS is a Russian abbreviation of ‘simplified satellite’) for a satellite weighing 100kg.

Spoutnik 1 couleur

It was thus that, on the night of the 4th and 5th October 1957 an instrument, then mysterious, was launched from an equally mysterious corner of Central Asia. In fact it was not until 1961 that the Baikonur cosmodrome, close to the city of Lenin-Tiouratam in the Kazakhstan steppes, was revealed to the public. The device launched fifty years ago was the first artificial satellite, called Sputnik-1. This Russian word means ‘travelling companion’: following the example of the Moon, this first satellite kept the company of our planet on its journey around the Sun.

A lifespan of three months

Sputnik-1 was placed in orbit by a Semiorka rocket – during what was then its fifth flight, the previous two having been successful – in its intercontinental missile R7 version. With a take-off mass of 280 tons – 9/10 of which were made up of propellant fuels – it provided the PS-1 satellite with a speed of 28,000 km per hour (7.8 km/s) And this at the end of a powered flight of hardly five minutes duration to stay on course for space! In ejecting the cap its central stage released a 0.58m steel aluminium sphere, pressurized with nitrogen and bristling with four long antennae: the first Sputnik. This glistening ball weighed 83.6kg, of which two thirds was made up of silver-zinc batteries. Placed in a terrestrial orbit between an altitude of 228 and 950km, the satellite carried out its journey in free-fall: it ‘fell’ whilst making circuits of the planet.

Sputnik-1 thus revolved for three months before being consumed in the atmosphere on 4th January, 1958. It has entered History as the symbol of the beginning of the space odyssey. Its replica was the star of the USSR pavilion, not far from the Atomium at the Brussels Expo in 1958.

Audible, if not visible

signal

In Moscow the Kremlin rulers, with Nikita Khrushchev at their head, were not expecting the mission to succeed at the first attempt. They were caught on the back foot by the shockwave effect Sputnik had on worldwide opinion. They nevertheless understood very quickly that the Soviet regime had, with this cosmic première, in its hands a propaganda weapon in the cold war that saw it confronted by the United States. And the stares fixed skywards in order to see this ‘baby-moon’ passing overhead: but the object that sparkled in the sun was the Semiorka rocket stage, with a length of 28m. Whilst it was invisible, Sputnik-1 nonetheless made itself heard: its strident ‘bip-bips’, beamed out by two transmitters at 20 and 40 MHz (15 and 7.5 longwave), could be captured by radio enthusiasts over the entire world. The data transmitted by this first satellite were the sphere’s internal and external temperatures, and they were used to analyse the spread of signals in the ionosphere.



Signal from the Russian space satellite

Barks in the cosmos

The team of engineers and technicians – Russian and Ukrainian – who had succeeded in the feat of launching the satellite had not finished furnishing surprises and sadness. At first, in the words of Oleg Ivanovsky, deputy-designer of the Sputnik mission – who is today 85 years old – these shadowy workers were upset at having been in some way deprived of the confidentiality of their work: what was supposed to be a state secret at the heart of the military-industrial complex found itself on the front pages the world over!

Once they had returned to Moscow this team, placed under the leadership of the designer-in-chief Sergey Korolev – whose identity was only revealed in January 1966 at his Red Square funeral! – were put under pressure by the Kremlin: another great feat must be accomplished to coincide with the 40th anniversary celebrations of the October Bolshevik Revolution. The engineers and technicians set to work once again, night and day, to produce another satellite, this time inhabited. Sputnik-2 was fitted out on the basis of the first ‘baby-moon’: under a sphere which sheltered the transmitters and electronic equipment was installed a pressurised chamber furnished with survival systems (oxygen, water, food), a nappy to collect excrement, and a series of electrodes.

There was no question of going as far as recovering the passenger of this second satellite. With a mass of half a ton it was placed in orbit on 3rd November, 1957. On board was a dog, Laika, which weighed 6kg. She was supposed to live for a week but, due to the suffocating heat of her non air-conditioned passenger cell, she succumbed at the end of one day’s flight.

American delays

Spoutnik 2 EN

In the face of the Soviet Empire’s space performances, made possible by the power of the Semiorka rocket, the Americans took fright. They were aware that Moscow had available an intercontinental missile with a range of 8.000 km, capable of striking North America with a nuclear weapon. Their pride had taken a blow: Russian was being spoken in the cosmos! Washington tried to save its honour in December 1957 by launching a micro-satellite, weighing 1.5km, which resembled a grapefruit (from whence its name). But the US Navy’s small Vanguard rocket crashed during its Cape Canaveral lift-off, which was given a lot of media attention. And the newspapers headlined with bitter irony: Flopnik! Kaputnik! The humiliation was at its peak.

As a matter of urgency the American President Dwight Eisenhower and the federal authorities called to the rescue the engineer Wernher von Braun and his Redstone Arsenal team, working at the heart of the US army, which had produced a Jupiter-C rocket which could have been used from the autumn of 1956 onwards – a year before the Soviet Semiorka! – to launch a ‘made in the USA’ satellite. On 31st January 1958 this medium range rocket placed into orbit Explorer-1, which discovered the Van Allen radiation belts (named after the scientist who had equipped the satellite with Geiger counters). On 1st October 1958 America mobilized itself around a national organization for aeronautics and space: NASA was born. Thanks to this centralized organisation it aimed at overcoming its lagging behind in what was to become the race to put a human in space (Yuri Gagarin in April 1961), and then the race for the first steps on the Moon (Neil Armstrong and Buzz Aldrin in July 1969).

The price of a gold bar…

Space exploration has granted respectability and nobility to rockets, the heirs to V2 and other missiles of destruction. They regularly place satellites in orbit around the Earth for scientific missions, telecommunications, television, navigation, observations of the planet, etc. It is they that enable manned spaceflight and which dispatch probes to the Moon, the planets Venus and Jupiter, and as far as the edges of the solar system. Interplanetary probes such as Voyager, which, on route to the stars, find themselves at tens of millions of kilometres from our Earth.

Sputnik-1 did not remain alone in space for long. Since the first Sputnik of 1957, the United Nations Office for Outer Space Affairs has logged some 4,550 successful launches of 5,900 satellites. By the 15th of last August, the Space Surveillance Network at NORAD (North American Aerospace Defense Command) had catalogued 12,328 space objects (of terrestrial origin) of at least 10cm that one can detect and whose orbit can be followed: 3,197 satellites or probes and 9,131 pieces of various debris (bits of wreckage, bits of satellite, stages, fragments). A list which is regularly updated with national registrations is published by NORAD. As far as smaller bits of debris are concerned, the ‘Orbital Debris’ office of NASA’s Johnson Space Center estimates that there are over 100,000 pieces of debris measuring between 1 and 10cm, and tens of millions particles of less than a centimetre. They are spread out in low orbits of between altitudes of 500 and 2,000km and are concentrated close to the geostationary ring between 35,000 and 37,000km.

History will record that it was a Russian built Semiorka that showed the way into space. This rocket, designed in the middle of the 1950s is still very much in fashion! This doyen has 1,723 successful launches of space instruments to its name. Europe has chosen to use it from 2009 onwards to fill out what its services have to offer in terms of spatial transport by using Ariane 5 and Vega.

Fifty years after the technological feat that was Sputnik-1, access to space remains a risky and costly gamble. The cost of putting 1kg into orbit, insurance costs included – the risks of launch failures need to be covered – comes to €15,000. The equivalent of the price of a gold bar! This cost represents a serious brake to the development of ambitious missions and competitive applications. Every new stage in mastering the dimensions of space is thus carried out through technological revolutions which render transport into orbit cheaper and cleaner.

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