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The air resistance does not depend on the angle at which a spacecraft enters the atmosphere. The angle does determine how long a spacecraft is in the upper regions of the atmosphere where the air is much less dense. A spacecraft needs to be there long enough to loose most of it's speed. The angle at which a spacecraft can approach the earth is called the re-...


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At altitudes below around 40 km the air density starts to increase quite rapidly, see https://www.translatorscafe.com/unit-converter/DE/calculator/altitude/#altidude-scheme-big. The air resistance is calculated as D=Cd*0.5*density*velocity^2, it is proportional to the density and proportional to the velocity squared. If a spacecraft enters the denser parts ...


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Going straight down takes a lot more fuel for deceleration. In order for a spacecraft to stay in orbit, it needs a substantial velocity perpendicular to the direction of the vector of gravitational force. This velocity is referred to as your orbital velocity; for a near-Earth orbit about 200 miles up, you need an orbital velocity of 7.79 km/s. In order for ...


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“Bouncing off the atmosphere” is a misleading turn of phrase. When returning to the Earth from the Moon, a spacecraft is on an elliptical orbit with the high end somewhere around the moon’s altitude and the low end just grazing the top of Earth’s atmosphere. The concern around a too-shallow reentry angle is that it won’t slow the spacecraft enough for a ...


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The resistance is proportional to the density of the air. If you come in at a shallow angle you decelerate more gently as you spend more time at a higher altitude.


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Data for planetary missions is stored in the Planetary Data System. This has an entry for the Galileo probe. Within the data files for the tmospheric Structure Instrument (ASI), there's a file called accel.txt which describes several files that contain acceleration data. Data in these files, e03z1.dat, e03z2.dat, e03an.dat, contain data for all of ...


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Probably interesting: CORONA: America's First Satellite Program Relevant chunk: The planned recovery sequence involved a series of maneuvers, each of which had to be executed to near-perfection or recovery would fail. Immediately after injection into orbit, the AGENA vehicle was yawed 180 gegrees so that the recovery vehicle faced to the rear. This ...


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The Vostok capsule wasn't stabilized during reentry. Friction from reentry was probably the major factor to not let it spin wildly. I couldn't find information about other flights, but the first one (Vostok-1) is described with following phrases from Gagarin's debriefing: Как только выключилась ТДУ, произошел резкий толчок, и корабль начал вращаться ...


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Reaction control system jet interactions with a vehicle's aerodynamic flowfield can be counterintuitive. Here's a capsule simulation results graphic showing similar spreading effects below the jet as well as laterally (from the first link below). This paper states in reference to Apollo: Interference heating in the case of the yaw and roll jets covered ...


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The orbiters were not allowed to fly through precipitation on landing for the following reasons: The orbiter is not to encounter precipitation on any approach due to decreased visibility, damage to the TPS, and the potential for triggered lightning. Undesirable aspects of thunderstorms include rain (TPS, structure), hail (TPS, structure, control), ...


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