MOSCOW: A Soviet spacecraft made a soft-landing on Venus today [Oct 18] and radioed back across 5.3 crore miles that the planet’s atmosphere was about 15 times as dense as that on earth.

Venus-4 also reported that the atmosphere consisted almost exclusively of carbon dioxide with traces of hydrogen vapour. The temperature of Venus ranged from 40 to 280 degrees Centigrade.

Observers said these first reports indicated that Venus could not support terrestrial life.

Soviet news agency “Tass” said Venus-4 entered the Venusian atmosphere at 0434 GMT today at a speed of 11 kilometres per second. The spacecraft was launched on its 117-day journey on June 12 after having been placed in an orbit around the earth.

The Soviet Union thus scored another resounding success in the exploration of space.

The scientific instruments, ejected from the spacecraft, were landed on the planet’s surface by a parachute that opened automatically, reported “Tass”. They sampled atmospheric conditions and almost immediately began sending the information back to earth from beneath the thick permanent veil of cloud which up till now had thwarted all optical telescopes.

“Tass” said the sampling showed that the Venusian atmosphere consists almost exclusively of carbon dioxide. Carbon dioxide makes up less than one-tenth of one per cent of earth’s atmosphere and only 1.5 per cent oxygen and water vapour.

The two main bases in the earth’s atmosphere are oxygen (21 per cent) and nitrogen (78 per cent). “Tass” said Venus-4’s instruments found no discernible trace of nitrogen on Venus.

Barometric pressure varied between one and 15 atmospheres.

The instruments discerned neither any magnetic field nor any radiation belts around the planet, but did find a weak layer of hydrogen.

“Tass” said Soviet scientists were analysing information sent back by the space probe, including data gathered on its four-month voyage from earth, and said it would be made public.

Published in Dawn, October 19th, 2017