Beta angle in the Earth's shadow, and results in extremely reduced absorption of solar energy. At a LEO of 280 kilometers, the object is in sunlight through 59% of its orbit (approximately 53 minutes in Sunlight, and 37 minutes in shadow.) On the other extreme, an object launched into an orbit parallel to the terminator results in a beta angle of 90 degrees (formula_2 = 90°), and the object is in sunlight 100% of the time. An example would be a polar orbit initiated at local dawn or dusk on an equinox. Beta angle can be controlled to keep a satellite as
Type 97 90 mm Infantry Mortar on the Type 94. Certain compromises in material and workmanship were made in the manufacture of the Type 97. The bipod feet and chain hooks were held to the legs of the bipod by pins, joined with solder, whereas on the Type 94 they are welded. No welds were polished on the Type 97, although no indications of fractures were reported despite the poor quality of the welding. The adjusting nut, sliding bracket, and hand wheels of the Type 97 are made of steel, rather than brass which was utilized in the Type 94. Type 97 90 mm Infantry Mortar