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East Siberian Laika • Laika (EHR testing framework) • Laika (band) • Laika (comic) • Laika (company) • Laika (disambiguation) • Laika (dog breed) • Laika Come Home • Laika Dog • Laïka Fatien • Neighborhood 2 (Laïka) • Planet Laika • Russo-European Laika • Ta Laïka Tis Despinas • The laika • West Siberian Laika
In 1957, Laika became the first animal launched into orbit, paving the way for human spaceflight. This photograph shows her in a flight harness.
|Species||Canis lupus familiaris|
Moscow, Soviet Union
|Died||November 3, 1957|
|Nation from||Soviet Union|
|Known for||First animal to orbit the earth|
As little was known about the impact of spaceflight on living creatures at the time of Laika's mission, and the technology to de-orbit had not yet been developed, there was no expectation of Laika's survival. Some scientists believed humans would be unable to survive the launch or the conditions of outer space, so engineers viewed flights by non-human animals as a necessary precursor to human missions. Laika, a stray dog, originally named Kudryavka (Russian: Кудрявка Little Curly), underwent training with two other dogs, and was eventually chosen as the occupant of the Soviet spacecraft Sputnik 2 that was launched into outer space on November 3, 1957.
Laika likely died within hours after launch from overheating, possibly caused by a failure of the central R-7 sustainer to separate from the payload. The true cause and time of her death was not made public until 2002; instead, it was widely reported that she died when her oxygen ran out on day six, or as the Soviet government initially claimed, she was euthanised prior to oxygen depletion. The experiment aimed to prove that a living passenger could survive being launched into orbit and endure weightlessness, paving the way for human spaceflight and providing scientists with some of the first data on how living organisms react to spaceflight environments.
On April 11, 2008, Russian officials unveiled a monument to Laika. A small monument in her honour was built near the military research facility in Moscow which prepared Laika's flight to space. It features a dog standing on top of a rocket.
After the success of Sputnik 1, Nikita Khrushchev, the Soviet leader, wanted a spacecraft launched on November 7, 1957, the 40th anniversary of the Bolshevik Revolution. A more sophisticated satellite was already under construction, but it would not be ready until December; this satellite would later become Sputnik 3.
To meet the November deadline, a new craft would have to be built. Khrushchev specifically wanted his engineers to deliver a "space spectacular," a mission that would repeat the triumph of Sputnik I, stunning the world with Soviet prowess. The planners settled on an orbital flight with a dog. Soviet rocket engineers had long intended a canine orbit before attempting human spaceflight; since 1951, they had lofted 12 dogs into sub-orbital space on ballistic flights, working gradually toward an orbital mission possibly some time in 1958. To satisfy Khrushchev's demands, the orbital canine flight was expedited for the November launch.
According to Russian sources, the official decision to launch Sputnik 2 was made on October 10 or 12, leaving the team only four weeks to design and build the spacecraft. Sputnik 2, therefore, was something of a rush job, with most elements of the spacecraft being constructed from rough sketches. Aside from the primary mission of sending a living passenger into space, Sputnik 2 also contained instrumentation for measuring solar radiation and cosmic rays.
The craft was equipped with a life-support system consisting of an oxygen generator and devices to avoid oxygen poisoning and to absorb carbon dioxide. A fan, designed to activate whenever the cabin temperature exceeded 15 °C (59 °F), was added to keep the dog cool. Enough food (in a gelatinous form) was provided for a seven-day flight, and the dog was fitted with a bag to collect waste. A harness was designed to be fitted to the dog, and there were chains to restrict her movements to standing, sitting or lying down; there was no room to turn around in the cabin. An electrocardiogram monitored heart rate and further instrumentation tracked respiration rate, maximum arterial pressure and the dog's movements.
Laika was found as a stray wandering the streets of Moscow. Soviet scientists chose to use Moscow strays since they assumed that such animals had already learned to endure conditions of extreme cold and hunger. This specimen was an eleven-pound mongrel female, approximately three years old. Another account reported that she weighed about 6 kg (13 lb). Soviet personnel gave her several names and nicknames, among them Kudryavka (Russian for Little Curly), Zhuchka (Little Bug) and Limonchik (Little Lemon). Laika, the Russian name for several breeds of dogs similar to the husky, was the name popularized around the world. The American press dubbed her Muttnik (mutt + suffix -nik) as a pun on Sputnik, or referred to her as Curly. Her true pedigree is unknown, although it is generally accepted that she was part husky or other Nordic breed, and possibly part terrier. A Russian magazine described her temperament as phlegmatic, saying that she did not quarrel with other dogs.
The Soviet Union and United States had previously sent animals only on sub-orbital flights. Three dogs were trained for the Sputnik 2 flight: Albina, Mushka, and Laika. Soviet space-life scientist Oleg Gazenko selected and trained Laika. Albina flew twice on a high-altitude test rocket, and Mushka was used to test instrumentation and life support.
To adapt the dogs to the confines of the tiny cabin of Sputnik 2, they were kept in progressively smaller cages for periods up to 20 days. The extensive close confinement caused them to stop urinating or defecating, made them restless, and caused their general condition to deteriorate. Laxatives did not improve their condition, and the researchers found that only long periods of training proved effective. The dogs were placed in centrifuges that simulated the acceleration of a rocket launch and were placed in machines that simulated the noises of the spacecraft. This caused their pulses to double and their blood pressure to increase by 30–65 torr. The dogs were trained to eat a special high-nutrition gel that would be their food in space.
Before the launch, one of the scientists took Laika home to play with his children. In a book chronicling the story of Soviet space medicine, Dr. Vladimir Yazdovsky wrote, "I wanted to do something nice for her: She had so little time left to live."
According to a NASA document, Laika was placed in the satellite on October 31, 1957—three days before the start of the mission. At that time of year the temperatures at the launch site were extremely cold, and a hose connected to a heater was used to keep her container warm. Two assistants were assigned to keep a constant watch on Laika before launch. Just prior to liftoff on November 3, 1957 from Baikonur Cosmodrome, Laika's fur was sponged in a weak alcohol solution and carefully groomed, while iodine was painted onto the areas where sensors would be placed to monitor her bodily functions.
At peak acceleration Laika's respiration increased to between three and four times the pre-launch rate. The sensors showed her heart rate was 103 beats/min before launch and increased to 240 beats/min during the early acceleration. After reaching orbit, Sputnik 2's nose cone was jettisoned successfully; however the "Block A" core did not separate as planned, preventing the thermal control system from operating correctly. Some of the thermal insulation tore loose, raising the cabin temperature to 40 °C (104 °F). After three hours of weightlessness, Laika's pulse rate had settled back to 102 beats/min, three times longer than it had taken during earlier ground tests, an indication of the stress she was under. The early telemetry indicated that Laika was agitated but eating her food. After approximately five to seven hours into the flight, no further signs of life were received from the spacecraft.
The Russian scientists had planned to euthanize Laika with a poisoned serving of food. For many years, the Soviet Union gave conflicting statements that she had died either from oxygen starvation when the batteries failed, or that she had been euthanized. Many rumors circulated about the exact manner of her death. In 1999, several Russian sources reported that Laika had died when the cabin overheated on the fourth day. In October 2002, Dimitri Malashenkov, one of the scientists behind the Sputnik 2 mission, revealed that Laika had died by the fourth circuit of flight from overheating. According to a paper he presented to the World Space Congress in Houston, Texas, "It turned out that it was practically impossible to create a reliable temperature control system in such limited time constraints."
Over five months later, after 2,570 orbits, Sputnik 2 disintegrated—along with Laika's remains—during re-entry on April 14, 1958.
Due to the overshadowing issue of the Soviet vs. US Space Race, the ethical issues raised by this experiment went largely unaddressed for some time. As newspaper clippings from 1957 show, the press was focused on reporting the political perspective, while the health and retrieval—or lack thereof—of Laika was hardly mentioned. Only later were there discussions regarding the fate of the dog—which some initially insisted be called Curly rather than Laika.
Sputnik 2 was not designed to be retrievable, and Laika had always been intended to die. The mission sparked a debate across the globe on the mistreatment of animals and animal testing in general to advance science. In the United Kingdom, the National Canine Defence League called on all dog owners to observe a minute's silence, while the Royal Society for the Prevention of Cruelty to Animals (RSPCA) received protests even before the Soviet Union had finished announcing the mission's success. Animal rights groups at the time called on members of the public to protest at Soviet embassies. Others demonstrated outside the United Nations in New York; nevertheless, laboratory researchers in the U.S. offered some support for the Soviets, at least before the news of Laika's death.
In the Soviet Union, there was less controversy. Neither the media, books in the following years, nor the public openly questioned the decision to send a dog into space. It was not until 1998, after the collapse of the Soviet regime, that Oleg Gazenko, one of the scientists responsible for sending Laika into space, expressed regret for allowing her to die:
Work with animals is a source of suffering to all of us. We treat them like babies who cannot speak. The more time passes, the more I'm sorry about it. We shouldn't have done it... We did not learn enough from this mission to justify the death of the dog.
Laika is memorialized in the form of a statue and plaque at Star City, Russia, the Russian Cosmonaut training facility. Future space missions carrying dogs would be designed to be recovered. The only other dogs to die in a Soviet space mission were Pchyolka and Mushka, who died when Korabl-Sputnik 3 accidentally disintegrated on re-entry on December 1, 1960.
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