Sputnik 2, or Prosteyshiy Sputnik 2 was the second spacecraft launched into
Earth orbit, on 3 November 1957, and the first to carry a living animal, a dog
named Laika. Sputnik 2 was a 4-metre high cone-shaped capsule with a base
diameter of 2 meters that weighed around 500 kg, though it was not designed to
separate from the rocket core that brought it to orbit, bringing the total
mass in orbit to 7.79 tons. It contained several compartments for radio
transmitters, a telemetry system, a programming unit, a regeneration and
temperature-control system for the cabin, and scientific instruments. A
separate sealed cabin contained the dog Laika.
Engineering and biological data were transmitted using the Tral D telemetry
system, transmitting data to Earth for a 15-minute period during each orbit. Two
photometers were on board for measuring solar radiation and cosmic rays. Sputnik
2 did not contain a television camera; TV images of dogs on Korabl-Sputnik 2
are commonly misidentified as Laika. Mission profile
Sputnik 2, known to Korolev's design bureau as "Prosteyshiy Sputnik-2",
meaning "Simple Satellite 2", was launched into a 212 × 1660 km orbit with
a period of 103.7 minutes on a modified ICBM R-7, similar to the one used to
launch Sputnik 1. The R-7 was also known by its GURVO designation 8K71, as well
as the T-3, M-104, and Type A. The R-7 modified for the PS-2 satellite launch
was designated 8k71PS. Unlike Sputnik 1, Sputnik 2 was not designed to detach
from the R-7 sustainer core, since Sputnik 1's core stage had demonstrated
an acceptable orbital lifespan. This allowed the core's Tral D telemetry
system to be used to transmit data, but would lead to speculation that Sputnik 2
had failed to separate. After reaching orbit, interior temperatures rapidly
climbed to over 40 °C, and Laika survived for only a few hours instead of
the planned ten days. The orbit of Sputnik 2 decayed, and it re-entered
Earth's atmosphere on 14 April 1958 after 162 days in orbit.
Passenger The first living creature to enter orbit
was a female mongrel originally named Kudryavka but later renamed Laika. Her
true pedigree is unknown, although it is generally accepted that she was part
husky or other Nordic breed, and possibly part terrier. NASA refers to
Laika as a "part-Samoyed terrier". Laika was selected from ten candidates at the
Air Force Institute of Aviation Medicine, because of her even
temperament. She weighed about 6 kg. The pressurized cabin on Sputnik 2 allowed
enough room for her to lie down or stand and was padded. An air regeneration
system provided oxygen; food and water were dispensed in a gelatinized form.
Laika was chained in place and fitted with a harness, a bag to collect waste,
and electrodes to monitor vital signs. Early telemetry indicated Laika was
agitated but alive and well, though the cabin temperature had already reached 43
°C by the third orbit. Biometric telemetry failed sometime after the
fourth orbit. While it was initially claimed that Laika had survived in orbit
for a week, decades later Russian sources revealed that Laika likely lived
only a few hours in orbit before dying from overheating. The mission provided
scientists with the first data on the behavior of a living organism in the
space environment. Sputnik 2 and the Van Allen radiation
belt Sputnik 2 detected the Earth's outer
radiation belt in the far northern latitudes, but the significance of the
elevated radiation was not realized. In Australia, Professor Harry Messel
intercepted the signals, but the Soviets would not provide the code, and the
Australians would not send the data. In 1958, with Sputnik 3, they began to
cooperate and confirmed the findings of the U.S. satellites Explorer 1, 3, and
4. Replicas
A copy of Sputnik 2 that was used in testing before the launch is located at
Kansas Cosmosphere and Space Center in Hutchinson, Kansas.
Footnotes See also
Timeline of artificial satellites and space probes
References Bilstein, Roger E., "Stages to Saturn a
Technological History of the Apollo/Saturn launch Vehicles",
Washington D. C., National Aeronautics and Space Administration, NASA SP 4206.
Cox, Donald & Stoiko, Michael, "Spacepower what it means to you",
Philadelphia, Pennsylvania, The John C. Winston Company.
Harford, James., Korolev, New York. John Wiley & Sons, Inc., ISBN 0-471-14853-9.
Siddiqi, Asif A., Sputnik and the Soviet Space Challenge, Gainesville, FL. The
University of Florida Press, ISBN 0-8130-2627-X.
Swenson, L, Jr, Grimwood, J. M. Alexander, C.C., This New Ocean, A
History of Project Mercury, Washington D. C., National Aeronautics and Space
Administration, Library of Congress Card No. 66-62424.
Zaloga, Stephen J., The Kremlin's Nuclear Sword, Washington. The
Smithsonian Institution Press, ISBN 1-58834-007-4.
External links Sputnik: 50 Years Ago
Anatoly Zak on Sputnik-2 Sputnik 2 Diary
NSSDC Master Catalog: Spacecraft Sputnik Sputnik 2 at Astronautix
Usilaika - More about Laika