It has been suggested that this orbit would be useful for meteorological observations of the high latitudes ( Kidder and Vonder Haar, 1990). The former Soviet Union also used a highly elliptical orbit for Molniya communications satellites. The former Soviet Union placed its Meteor satellites in low Earth orbit with inclination angles of about 82° (see Appendix A). ![]() It was placed in this orbit so that it would precess with respect to the sun and sample all local times (see Section 2.6) over the course of a month. The Earth Radiation Budget Satellite (ERBS) was launched from the Space Shuttle and orbits at an altitude of 600 km with an inclination angle of 57°. Others have been and will become useful for meteorological satellites. Geostationary and sunsynchronous are only two of infinite possible orbits. Vonder Haar, in Satellite Meteorology, 1995 2.4.3 Other Orbits ZSM-5 (MFI) synthesis was also performed in space, and crystals of up to 160 × 145 × 100 μm were produced. The largest crystals of up to 215 μm of zeolite NaX were obtained under microgravity. Their studies showed that ∼15–40% fewer nuclei for zeolites NaA and ∼40–60% fewer nuclei for zeolite NaX were observed in orbit. It was found that crystals synthesized in microgravity by mixing the precursor solutions in orbit were ∼25–70% larger in linear dimension compared to their ground-based controls. In 2000, Sacco and co-workers carried out zeolite crystallization of NaA (LTA) and NaX (FAU) in the reaction system Na 2O-Al 2O 3-SiO 2-H 2O-TEA on four separate space shuttle missions. It was hypothesized that this quiescent environment would promote the growth of larger single crystals by allowing crystals to grow at a longer residence time in a high-concentration nutrient field, and these crystals would have a high degree of crystalline perfection. In comparison with the conventional hydrothermal synthesis carried out on earth, these low-gravity levels in space may isolate the effects of natural convection, that affects the formation of defects, and minimize sedimentation. The low-gravity environment aboard the space shuttle (10 −3–10 −6g) can provide a unique environment for zeolite crystal growth. Jihong Yu, in Studies in Surface Science and Catalysis, 2007 3.1.3 Synthesis under microgravity At 73.214 s a second flash was seen that increased within milliseconds (at 73.327 s) to full size of explosion, see Figure XIII-27, a height of 14,000 m and a speed of Ma = 1.92. At 73.191 s a first flash, attributed to the ruptures of both tanks was observed. Full heating of this tank occurred at 60 s, and a first leak of the hydrogen tank was observed at 64.66 s, and after 73.137 s a hydrogen release occurred. One insulation at the lower end of the right-hand rocket (seen in the direction of flight) opposite to the tank of the liquid hydrogen leaked, so that within 0.678 up to 2.500 s from lift off fume drops escaped, 3 to 4 per second, and after 58.788 s flames appeared towards the hydrogen tank. In this process a careful insulation between the segments is essential to prevent a flash through. These single pieces had been transported from the factory to the starting place where they had been assembled to the rocket motor. For additional thrust there had been applied two solid propellant rocket motors (delivering over about 2 minutes 80% of the total thrust) of 45.56-m length and 3.7-m ∅, consisting of 11 pieces each. This mass is intended for consumption within 8 1/2 minutes of liftoff by three nozzles. ![]() ![]() In the lower part was 1,450 m 3 liquid hydrogen and in the upper tank 541 m 3 liquid oxygen, in total a bit more than 790 t. The space shuttle was set on a main tank of 8.36 m diameter and 46.8 m length containing two tanks.
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