Mercury, missions

Until now, Mercury has only been studied more closely by one spacecraft (Mariner 10, 1974), since its nearness to the sun means that spacecraft approaching it are subject to particularly extreme conditions. NASA s MESSENGER (Mercury Surface, Space, Environment, Geochemistry and Ranging) was launched in 2004 and is planned to reach Mercury in March 2011, and then to orbit the planet. The main tasks of the MESSENGER mission are to map the planet, to make measurements of its magnetic field and to collect data relevant to its geological and tectonic history (Solomon, 2007). 

In this chapter we summarize what we know about the chemical composition of Mercury, with emphasis on assessing the amount of FeO in the bulk planet. FeO is a particularly useful quantity to evaluate the extent to which Mercury is enriched in refractory elements, because its concentration increases with decreasing temperature in a cooling gas of solar composition (e.g., Goettel, 1988). We then examine models for the composition of Mercury and outline tests that future orbital missions to Mercury will be able to make. 

Watring, D.A. Alexander, H.A. Jerman, G.A. Effect of residual accelerations during microgravity directional solidification of mercury cadmium telluride on the USMP-2 mission. J. Cryst. Growth 1997, 174, 101-107. 

Exploring the moon a site devoted to the U Mercury, Gemini and Apollo missions... 

The next sections present water quality from 1994 to 1998 on the specific Danube River profiles (where the water was contfolled with the BTF mission), giving maximum and 5-year average values of pollution by pettoleum hydrocarbons, mercury and other hazardous substances that were also controlled after the NATO bombing. 

In the investigated section of the Danube (upstream and downstream from Novi Sad) during the BTF mission, shell samples were tested for PAHs, PCBs and mercury [40, 54, 3], All samples of Sinanodonta woodiana (Lea, 1834) had considerably higher contents of PAHs compared to concentrations in A. anatina specimens. The highest concentrations of PAHs in S. woodiana specimens were found upstream from Novi Sad. Among the examined PAHs, naphthalene has the highest concentration of 2.63 mg kg . 

The National Aeronautics and Space Administration (NASA) asked PUlsbury Company food scientists to help them develop preserved foods that would not produce crumbs. Mercury, Gemini, and early Apollo program crews consumed foods contained in tubes. NASA arranged for Oregon Freeze Dry to use its freeze-drying technology to preserve more elaborate meals for astronauts to eat during later Apollo and space shuttle missions. 

In the 1970 s, interplanetary spacecraft ranged far from the Sun and strained the capabilities of solar panels to provide sufficient electrical power. Spacecraft engineers harnessed the energy of radioactive decay to power deep-space missions and to keep the spacecraft warm so far from the Sun. Missions to Mercury and Venus, so near the Sun, posed the opposite challenge of keeping the spacecraft from overheating. 

European planetary missions such as the Rosetta spacecraft in 2003, the Mars Express in 2003, and the BepiColombo Mercury planetary orbiter planned for July 2016... 

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