



The dog Laika, the first living creature to orbit the Earth, did not live nearly as long as Soviet officials led the world to believe.

The animal, launched on a one-way trip on board Sputnik 2 in November 1957, was said to have died painlessly in orbit about a week after blast-off.

Now, it has been revealed she died from overheating and panic just a few hours after the mission started.

The new evidence was presented at the recent World Space Congress in Houston, Texas, US, by Dimitri Malashenkov of the Institute for Biological Problems in Moscow.

Noted space historian Sven Grahn told BBC News Online that the new information was surprising and significant as it ended more than 40 years of speculation about Laika's fate.

Space pioneer

Laika's mission on board Sputnik 2 stunned the world. Sputnik 1, the world's first satellite, had been launched less than one month before.

It was a metal sphere weighing about 18 kg (40 lbs) and was far heavier than anything the United States was contemplating launching.

An astonished world witnessed the launch of Sputnik 2 weighing 113 kg (250 lbs) and carrying the first living thing to go into orbit - the dog Laika.

The animal had been a stray wandering the streets of Moscow when she was captured and prepared for a space mission.

Shortly after launch the Soviets said that Laika was not destined to return alive and would die in space. The statement caused outrage to many observers.

Racing pulse

Dr Malashenkov has now revealed several new details about Laika's mission, such as her food being in jelly form and that she was chained to prevent her turning around.

There was a carbon dioxide absorbing device in the cabin to prevent the accumulation of this toxic gas, as well as an oxygen generator.

A fan was automatically activated to keep the dog cool when the capsule's temperature exceeded 15 deg Celsius.

According to Dr Malashenkov, a great deal of work had to be done to adapt a group of dogs to the conditions in the tight cabin of Sputnik 2. They were kept in gradually smaller cages for periods up to 15-20 days.

Three dogs were trained for the Sputnik 2 flight: Albina, Laika and Mushka. Albina was the first "backup", having flown twice on a high-altitude rocket. Mushka was used to test instrumentation and life support.

Death in space

Medical sensors placed on Laika indicated that during launch her pulse rate went up by a factor of three above its resting level.

At the start of weightlessness, her pulse rate decreased. It took three times longer than after a centrifuge ride on the ground to return Laika's heartbeat to pre-launch values, an indication of the stress she was suffering.

Dr Malashenkov also revealed how Laika died. Telemetry from the Sputnik 2 capsule showed that the temperature and humidity increased after the start of the mission.

After five to seven hours into the flight, no lifesigns were being received from Laika. By the fourth orbit it was apparent that Laika had died from overheating and stress.

Previously, it has been thought that Laika survived at least four days in space and perhaps even a week when Sputnik's transmitters failed.

Despite surviving for just a few hours, Laika's place in space history is assured and the information she provided proved that a living organism could tolerate a long time in weightlessness and paved the way for humans in space.

Laika's "coffin" circled the Earth 2,570 times and burned up in the Earth's atmosphere on 4 April 1958.