Venera 9

Venera 9 (Russian Венера -9) was a spacecraft of the USSR to the exploration of the planet Venus. She was launched on 8 June 1975 at 02:38:00 UTC from Baikonur on a Proton rocket and consisted of an orbiter and a lander and weighed 4936 kg. The orbiter was the first spacecraft to orbit Venus entered; the lander transmitted the first pictures from the surface of another planet. Your identical sister probe Venera 10 followed six days later.

Venera 9 and 10 were the first probes of the second generation of Soviet Venus probes, all previous Venus missions surpassed its enabled by new Proton rocket launch weight of approximately five tons of a multiple payload.

Lander

There were known on the ground by the Venera missions, the conditions, the USSR began to construct 1974 Venus landers which should not only provide atmospheric data, but also on the ground were able to carry out investigations.

Descent

The housed in a 2.5 m wide ball during flight Venera -9 lander separated from the orbiter on October 20, 1975 and entered with a relative velocity of 10.7 km / s in the Venus atmosphere. The descent was divided into the following phases:

• Braking atmosphere up to an altitude of 65 km and a speed of 250 m / s
• Parachute braking up to a speed of 150 m / s
• More parachutes opened, the channels were activated and transferred data
• In 62 km altitude, the three main parachutes opened with 180 m².
• In 50 km altitude, the three main parachutes were dropped, the lander was in free fall, the speed increased again, until they fell back through the denser atmosphere
• To 05:13 UTC beat the lander on Venus surface with a residual velocity of 7 m / s. The remaining energy is absorbed by a " Yielding ".

Work on the surface of Venus

For the first time, a coarse -resolution panoramic image was sent to Earth. This was the first image of the surface of an alien planet, a year before the Mars images from the Viking orbiters. Other instruments were a gas chromatograph to study the atmosphere, a sample collector and drill to study the physical structure of the surface. A seismometer worked, but delivered in the short time data. Before landing the equipment department had been cooled to -10 degrees Celsius, so Venera 9 worked 53 minutes longer than any spacecraft previously on the planet.

Orbiter

For the first time a planetary orbiter of the USSR was used. Shortly after the separation from the Orbiter Lander led by a course correction. The closest approach to Venus on October 22, 1975, the engines were fired a second time so that the orbiter into an orbit of 1510 × 112200 km einschwenkte, at an orbital period of about 48 hours. The orbiter itself sent photographs of Venus, which are comparable in detail with those of Mariner 6 and 7. Other instruments were a 8-30 micron radiometer for temperature measurement and a 350 -nm Ultraviolet photometer from CNES. A second VIS-Photometer/Polarimeter measured between 400 and 700 nm Then there was a 1.5-3 micron infrared spectrometer, a magnetometer and an ion trap. The orbiter weighed empty 2300 kg.