Laika and Sputnik 2 (1957): The First Animal in Orbit

Laika was a stray dog from the streets of Moscow who became the first animal to orbit Earth. She was launched aboard the Soviet satellite Sputnik 2 on 3 November 1957, less than a month after Sputnik 1, and her flight showed that a living creature could survive launch and weightlessness. But there was no way to bring her back, and she died within hours, making her mission one of the most debated episodes of the early Space Race.

Background: a second Sputnik in a hurry

The launch of Sputnik 1 on 4 October 1957 caused a sensation around the world. Soviet leader Nikita Khrushchev, delighted by the propaganda success, asked the chief designer Sergei Korolev for another spectacular launch in time for 7 November 1957, the 40th anniversary of the Bolshevik Revolution.

That left only about four weeks. Korolev’s engineers designed and built Sputnik 2 largely without formal drawings, adapting equipment that had been developed for high-altitude rocket flights with dogs. Soviet scientists had flown dogs on short vertical rocket flights since 1951, so they had experience of life-support systems and medical sensors. What they did not have was time to develop a heat shield or a method of bringing a capsule safely back from orbit.

Choosing and training the dogs

Soviet researchers preferred stray female dogs. Strays were thought to be hardy and used to cold and hunger, and females were easier to fit with the waste-collection equipment used in the cabin. The dogs had to be small, light and calm.

Three dogs were prepared for Sputnik 2: Laika, a mixed-breed female of about three years and around 6 kilograms; Albina, who had already flown on suborbital rockets and served as back-up; and Mushka, who was used to test instruments and life support. The programme’s medical side was led by Vladimir Yazdovsky, with Oleg Gazenko among the scientists who trained the dogs.

To prepare them for the cramped cabin, the dogs were kept in progressively smaller cages for up to several weeks. They were placed in centrifuges that imitated the acceleration of launch and in machines that reproduced the noise and vibration of a rocket. They also learned to eat a jelly-like nutrient food. Before the flight, surgeons implanted sensors so that her breathing, pulse and blood pressure could be measured in orbit.

Laika was known by several names in the Soviet press, including Kudryavka (“little curly one”). “Laika”, the name that stuck, is the name of a group of northern hunting-dog breeds and means roughly “barker”. Western newspapers nicknamed the satellite “Muttnik”.

The flight of Sputnik 2

Laika was placed in her pressurised cabin on 31 October 1957, three days before launch, and kept there while final checks were made. Sputnik 2 lifted off from the Tyuratam test range in Kazakhstan, later known as the Baikonur Cosmodrome, at about 05:30 Moscow time on 3 November 1957 (02:30 GMT).

At 508 kilograms, Sputnik 2 was about six times heavier than Sputnik 1. As well as Laika’s cabin, it carried instruments to measure solar radiation and cosmic rays. Unlike its predecessor, the satellite remained attached to the R-7 rocket’s core stage. Its orbit took it from about 212 kilometres to about 1,660 kilometres above Earth, with one circuit taking around 104 minutes.

Data radioed to the ground showed that Laika survived the launch. Her heart rate more than doubled during the climb to orbit and took about three hours of weightlessness to settle, far longer than in ground tests, a sign of severe stress. She did, however, move and eat, which was important evidence that an animal could live through weightlessness.

The death of Laika

Things soon went wrong. Part of the insulation was damaged during launch, and because the satellite had not separated from the rocket stage, the cabin’s temperature control could not cope. Readings showed the temperature rising to about 40 °C. Between about five and seven hours into the flight, around the fourth orbit, the sensors stopped showing signs of life.

For decades Soviet sources said that Laika had lived for several days and been painlessly put to death, often with the suggestion that she had eaten a final, poisoned meal prepared for that purpose. The true story was confirmed publicly only in 2002, when the Russian scientist Dimitri Malashenkov, who had worked on the programme, told an international space conference that she had died from overheating and stress within hours.

Sputnik 2 continued to circle the planet without her. It re-entered the atmosphere and burned up on 14 April 1958, after about 2,570 orbits.

Reaction and controversy

The flight was a further propaganda triumph for the Soviet Union and deepened alarm in the United States, already shaken by Sputnik 1. A satellite of more than half a tonne suggested that Soviet rockets could carry very heavy loads, including nuclear warheads.

It also caused protests. Animal welfare groups in Britain and other countries objected when it became clear that the dog would not return. In Britain the National Canine Defence League asked dog owners to observe a minute’s silence for her, and protesters gathered outside Soviet embassies. Supporters of the mission replied that animal experiments were already common in medical research and that the knowledge gained would protect future human crews. Debate continued for decades. Later in life Oleg Gazenko said publicly that he regretted the mission, arguing that the science gained had not justified the dog’s death.

Legacy

Laika’s flight had practical results. It showed that launch, weightlessness and the space environment were survivable for a mammal for at least several hours, an important step before human spaceflight. Many more dogs followed. On 19 August 1960 Belka and Strelka orbited Earth aboard Sputnik 5 and returned safely, and in April 1961 Yuri Gagarin became the first human in space.

The United States followed a parallel path with monkeys and chimpanzees; its first satellite, Explorer 1, was launched in January 1958 without any animal on board.

Laika herself became an icon. She appeared on postage stamps across the Eastern Bloc and beyond, on cigarette packets and in songs and books. On 11 April 2008 a small monument showing a dog standing on a rocket was unveiled in Moscow, near the military research institute where she had been prepared for flight. She is also depicted on the Monument to the Conquerors of Space in the city.

Timeline

• 1951, July: Soviet scientists begin launching dogs on short suborbital rocket flights.
• 1957, 4 October: Sputnik 1 is launched, the first artificial satellite.
• 1957, mid-October: Khrushchev asks for a second satellite for the revolution’s anniversary; work on Sputnik 2 begins.
• 1957, 31 October: Laika is placed in her cabin at the launch site.
• 1957, 3 November: Sputnik 2 is launched with Laika on board; she dies within hours.
• 1958, 14 April: Sputnik 2 re-enters the atmosphere and burns up.
• 1960, 19 August: Belka and Strelka orbit Earth aboard Sputnik 5 and return alive.
• 2002: The true cause and timing of Laika’s death are made public.
• 2008, 11 April: A monument to Laika is unveiled in Moscow.

Why it matters

Laika was the first living creature to orbit Earth, and her flight was a key step towards human spaceflight. Her story also raised lasting questions about the use of animals in research. She is remembered both as a pioneer of the Space Age and as a symbol of its costs.