Venus exploration

Liquid water is difficult to find in the universe. Scientists have found frozen ice in places such as Mars and gaseous water vapor in atmospheres such as that on Venus. However, no one has been able to find liquid water anywhere other than on Earth. Water is the only natural substance that is found in all three states of matter (solid, liquid, and gas) at the temperatures normally found on Earth. By exploring a few of the properties of water, you will discover what makes water unique. 

Post-WWII. After WWII most LP R D shifted from Germany to the USA and the USSR. Technical progress since 1945 in LP for rockets can be characterized by a host of minor improvements rather than major advances, and some spectacular applications of LP in rockets for military use and for space exploration, eg, in ICBM s (Intercontinental Ballistic Missiles) and in USA USSR Moon, Mars Venus shots . Thus the major developments since WWII have been primarily in the application of existing, though improved, propulsion systems to such highly publicized rockets as Sputnik, Vanguard, Soyuz, Saturn, Vostok, Apollo, Explorer, etc... 

The recent advances in modem technology continue to open new opportunities for the observation of chemical reactions on shorter and shorter time scales, at higher and higher quantum numbers, in larger and larger molecules, as well as in complex media, in particular, of biological relevance. As an example of open questions, the most rapid reactions of atmospheric molecules like carbon dioxide, ozone, and water, which occur on a time scale of just a few femtoseconds, still remain to be explored. Another example is the photochemistry of the atmospheres of nearby planets like Mars and Venus or of the giant planets and their satellites, which can help us to understand better the climatic evolution of our own planet. 

Marov M. Ya. (1972) Venus a perspective at the beginning of planetary exploration. Icarus 16, 415-461. 

Most of NASA s anticorrosion efforts are concentrated on the launch site, where the high temperamres of the launch and the humid coastal atmosphere encourage corrosion. However, corrosion is a concern in other aspects of the space program, as well. Batteries used in the International Space Station (ISS) must be prevented from corroding in the ISS s artificial, earth-like atmosphere NASA s mission of planetary exploration requires that scientists know the corrosivity of a planet s atmosphere before a craft can land safely. Venus, for example, has a highly corrosive atmosphere that makes lander design very difficult. 

The ionosphere of Venus is the most explored and best understood one in our solar system besides that of the earth. The atmosphere at the surface of Venus consists of approximately 96.5% CO2 and 3.5% N2. Photodissociation of CO2 results in atomic oxygen becoming the major atmospheric constituent above about 150 km. The behavior of the ionosphere of Venus is controlled by chemical processes below an altitude of about 180 km. This region of the ionosphere is analogous to the terrestrial E-region fi om the point of view that the main ion is molecular and is under chemical control. However, unlike the earth the maximum plasma density peaks near an altitude of 140 km (see Fig. 14), and is the result of a peak in the photoionization rate. Venus is an excellent example of the importance of chemical processes in establishing the nature of some of the important aspects of an ionosphere. The ion with the largest density is Oj, and yet there is practically no neutral O2 in the upper atmosphere. As mentioned earlier, the major neutral gas constituents in the upper atmosphere are CO2 and O. The photoionization of these neutral gas species is followed by the reactions indicated below, which very effectively turn these initial ions into 02" ... 

Spacecraft simultaneously in the Jovian system. Additionally, the decadal survey recommended that NASA should select its fourth mission in the New Frontiers program from among the following mission concepts Comet Surface Sample Return, Lunar South Pole Aiken Basin Sample Return, Saturn probe, Trojan Tour and Rendezvous, and Venus In Situ Explorer. 

The Pioneer Venus mission (1978) explored the atmosphere of Venus. One of the payloads was a GC system equipped with two gas columns and a TCD detector. Tlie system was used to analyze samples of the atmosphere during the probe s descent to determine the composition of Venus lower atmosphere. From these measurements, deductions were made of the gaseous sources of infrared opacity, the degree of differentiation of Venus interior, the degree of similarity between the solid bodies of Earth and Venus, and the evolution of Venus atmosphere to determine the composition atmospheric composition measurements [50]. 

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