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Sputnik 2

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Sputnik 2 was a landmark Soviet spacecraft launched on November 3, 1957. It was the second artificial satellite to orbit the Earth. More importantly, it was the first spacecraft to carry a living animal into orbit. This mission used a dog named Laika to help scientists understand how living beings react to space.

Photograph of Sputnik 2 taken from Patrick AFB in March 1958
Photograph of Sputnik 2 taken from Patrick AFB in March 1958

The mission was a major success for the Soviet Union during the Space Race. It proved that heavy payloads could be lifted into orbit. It also allowed for the long-term collection of scientific data from above the atmosphere.

The spacecraft was a cone-shaped capsule with a base diameter of 1.0 meter. It weighed approximately 500 kilograms on its own. However, it was not designed to separate from its rocket core, the Blok A. This meant the total mass in orbit was about 1,035 kilograms. The satellite contained several complex systems to function in space. These included radio transmitters and a telemetry system to send data home. It also had a programming unit and a system to control temperature and air.

Ussrsputnik2-20kop1957scott2032
Ussrsputnik2-20kop1957scott2032

A separate, sealed cabin was built specifically to house the passenger.

Inside the pressurized cabin, Laika was prepared for the journey. She was a part-Samoyed terrier weighing about 3.5 kilograms. Because the mission was planned so quickly, she could not undergo special training. Instead, engineers chose her from dogs already trained for suborbital flights. She was selected because of her even temperament. To monitor her health, scientists attached telemetry wires to her body. These wires tracked her pulse, respiration frequency, and blood pressure.

Atmospheric electromagnetic opacity
Atmospheric electromagnetic opacity

The cabin was padded and included food and water in a gelatinized form. A television camera also recorded her movements at 10 frames per second.

The history of Sputnik 2 is a story of intense pressure and speed. Originally, Soviet engineers planned a much larger satellite called "Object D." This advanced craft was meant to be much heavier and more scientific. However, the government wanted to launch something before the United States could. Sergei Korolev, the head of OKB-1, proposed a simpler design called the "Primitive Satellite" or PS. After Sputnik 1 launched in October 1957, leader Nikita Khrushchev demanded a second launch. He wanted it ready for the 40th anniversary of the Bolshevik revolution. This gave the engineers only three weeks to build the new mission.

Sputnik 2 was also a vital platform for solar and cosmic research. The Earth's atmosphere blocks certain types of light from the Sun. For example, X-rays and ultraviolet rays cannot be studied easily from the ground.

Atmospheric electromagnetic opacity
Atmospheric electromagnetic opacity

To solve this, the satellite carried two spectrophotometers. These instruments, provided by Professor Sergei Mandelstam, measured solar X-rays and ultraviolet rays. The spacecraft also carried a cosmic ray detector built by a team from Moscow University. This detector used Geiger counters to find high-energy charged particles. During its flight, the detector found that particle flux increased with altitude.

Life on the spacecraft was extremely stressful for the living passenger. During the early acceleration of the launch, Laika's heart rate jumped from 103 to 240 beats per minute. Her breathing also increased significantly. While she initially appeared agitated, telemetry showed she was eating her food. However, the mission faced a major engineering problem with temperature control. Because the satellite did not separate from the Blok A, heat built up quickly. A scientist named Dimitri Malashenkov later revealed that the cabin eventually overheated. It is believed Laika died from this heat on the fourth day of the mission.

The mission had a massive geopolitical and social impact. The successful launch showed that Soviet missiles were very powerful. This caused great concern in the United States and led to debates about space technology. At the same time, the mission sparked a global debate about animal testing. Many groups protested the use of animals to advance scientific goals.

Ussrsputnik2-20kop1957scott2032
Ussrsputnik2-20kop1957scott2032

After circling the Earth 2,370 times over 162 days, the spacecraft finally reentered the atmosphere. On April 14, 1958, it burned up while falling over the north Atlantic Ocean.

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Ussrsputnik2-20kop1957scott2032.jpg
File:Photograph of Sputnik 2 taken from Patrick AFB in March 1958.jpg
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