TSTI Admin No Comments June 20, 2024

ablation

A re-entry-vehicle’s surface is coated with a material having a very high latent heat of fusion, such as carbon or ceramics. As this material evaporates or vaporizes, it soaks up large amounts of heat energyWe use the angle of incidenceWe use the angle of incidence, θ, to determine how much solar energy hits a solar panel. This angle lies between a line perpendicular to the cell and the Sun line. More, θ, to determine how much solar energyWe use the angle of incidence, θ, to determine how much solar energy hits a solar panel. This angle lies between a line perpendicular to the cell and the Sun line. More hits a solarWe use the angle of incidence, θ, to determine how much solar energy hits a solar panel. This angle lies between a line perpendicular to the cell and the Sun line. More panelWe use the angle of incidence, θ, to determine how much solar energy hits a solar panel. This angle lies between a line perpendicular to the cell and the Sun line. More. This angleWe use the angle of incidence, θ, to determine how much solar energy hits a solar panel. This angle lies between a line perpendicular to the cell and the Sun line. More lies between […]

TSTI Admin No Comments June 20, 2024

absorptivity

The fraction of incident electromagnetic energyWe use the angle of incidenceWe use the angle of incidence, θ, to determine how much solar energy hits a solar panel. This angle lies between a line perpendicular to the cell and the Sun line. More, θ, to determine how much solarWe use the angle of incidence, θ, to determine how much solar energy hits a solar panel. This angle lies between a line perpendicular to the cell and the Sun line. More energyWe use the angle of incidence, θ, to determine how much solar energy hits a solar panel. This angle lies between a line perpendicular to the cell and the Sun line. More hits a solarWe use the angle of incidence, θ, to determine how much solar energy hits a solar panel. This angle lies between a line perpendicular to the cell and the Sun line. More panelWe use the angle of incidence, θ, to determine how much solar energy hits a solar panel. This angle lies between a line perpendicular to the cell and the Sun line. More. This angleWe use the angle of incidence, θ, to determine how much solar energy hits a solar panel. This angle lies between a line perpendicular to the cell and the Sun line. More lies between a line perpendicular to the cell and the SunWe use the angle of incidence, θ, to determine how much solar energy hits a solar panel. This angle lies between a line perpendicular to the cell and the Sun line. More line. More that a material “soaks up” or absorbs, like a sponge. For example, black paint has relatively high absorptivityThe […]

TSTI Admin No Comments March 30, 2026

acceleration

How fast an object’s speedHow fast an object’s speedHow fast an object's speed is changing when we apply a force to it. During acceleration, speed increases. During deceleration, speed decreases. More is changing when we apply a forceAn object's increasing speed toward Earth's center, caused by the force of gravity (the force of attraction between two objects). More to it. During accelerationHow fast an object's speed is changing when we apply a force to it. During acceleration, speed increases. During deceleration, speed decreases. More, speed increases. During decelerationThe narrow, 3-dimensional tunnel a vehicle must fly through to successfully re-enter Earth’s atmosphere. It’s boundaries come from limits on the vehicle’s maximum deceleration, maximum heating, and expected landing accuracy. More, speed decreasesThe amount of air within a certain volume. Atmospheric density is higher at sea-level and decreases as you go up in altitude. More. More is changing when we apply a forceAn object's increasing speed toward Earth's center, caused by the force of gravity (the force of attraction between two objects). More to it. During accelerationHow fast an object’s speedHow fast an object's speed is changing when we apply a force to it. During acceleration, speed increases. During deceleration, speed decreases. More is changing when we apply a force to it. During accelerationHow fast an object's speed is changing when we apply a force to it. During acceleration, speed increases. During deceleration, speed decreases. More, speedHow fast an object's speed is changing when we apply a force to it. During acceleration, speed increases. During deceleration, speed decreases. More increases. […]

TSTI Admin No Comments March 30, 2026

acceleration due to gravity

An object’s increasing speedHow fast an object’s speedHow fast an object's speed is changing when we apply a force to it. During acceleration, speed increases. During deceleration, speed decreases. More is changing when we apply a forceAn object's increasing speed toward Earth's center, caused by the force of gravity (the force of attraction between two objects). More to it. During accelerationHow fast an object's speed is changing when we apply a force to it. During acceleration, speed increases. During deceleration, speed decreases. More, speed increases. During decelerationThe narrow, 3-dimensional tunnel a vehicle must fly through to successfully re-enter Earth’s atmosphere. It’s boundaries come from limits on the vehicle’s maximum deceleration, maximum heating, and expected landing accuracy. More, speed decreasesThe amount of air within a certain volume. Atmospheric density is higher at sea-level and decreases as you go up in altitude. More. More toward Earth’s center, caused by the forceAn object’s increasing speedHow fast an object's speed is changing when we apply a force to it. During acceleration, speed increases. During deceleration, speed decreases. More toward Earth’s center, caused by the forceAn object's increasing speed toward Earth's center, caused by the force of gravity (the force of attraction between two objects). More of gravityA projectile with a prescribed path that cannot be altered after it has burned its propellant and the laws of ballistics govern its course. When gravity is the only force on it, its path is elliptical. More (the force of attractionAn object's increasing speed toward Earth's center, caused by the force of gravity (the force of attraction between two objects). More between two objects). More of gravityA […]

TSTI Admin No Comments March 30, 2026

acceptable operating ranges

The subsystems’ designDesign is an intricate process involving reviewing constraints, identifying and characterizing the mission subject, deriving the payload and orbital requirements, determining spacecraft mass, powerOrbiting spacecraft periodically pass through Earth’s shadow (enter eclipse). During these eclipse periods, the incident solar energy drops to zero, and the solar cells stop producing power. More and other detailed designDesign is an intricate process involving reviewing constraints, identifying and characterizing the mission subject, deriving the payload and orbital requirements, determining spacecraft mass, power and other detailed design requirements, identifying potential launch vehicles, deriving operations systems requirements and iterating. More requirements, identifying potential launch vehicles, deriving operations systems requirements and iterating. More requirements within which they will function smoothly. For example, a payloadAn assembly of […]

TSTI Admin No Comments June 20, 2024

accuracy

The more timeThe timeThe time between successive passages of the Sun overhead, which is from noon one day to noon the next day. Because Earth’s orbit around the Sun is slightly elliptical, this time varies slightly during a year. More between successive passages of the Sun overhead, which is from noon one day to noon the next day. Because Earth’s orbitThe oval-shaped path that a spacecraft follows. Orbits come in various shapes and sizes, but each one has a purpose: to let the spacecraft do its job. Higher orbits require more propellant to get a spacecraft there. More around the Sun is slightly elliptical, this timeThe time between successive passages of the Sun overhead, which is from noon one day to noon the next day. Because Earth’s orbit around the Sun is slightly elliptical, this time varies slightly during a year. More varies slightly during a year. More a vehicle spends in the atmosphereThe reference frameThe reference frame used to analyze a space vehicle’s motion after leaving orbit until it lands. Its origin is at the vehicle’s center of mass at the beginning of re-entry. More used to analyze a space vehicle’s motionA rotating object’s spin rate. We use the right-hand rule to determine its direction. More after […]

TSTI Admin No Comments March 30, 2026

active attitude control

This type of spacecraft attitude controlA spacecraft has to have the right attitudeThe job of the attitude determination and control subsystem (ADCS) is to keep its spacecraft pointed in the right direction. More, or orientation, to point cameras and antennas at targets on EarthSolar energy reflected off Earth that accounts for about 20% of the total energy impacting low-Earth-orbiting spacecraft. More. For attitude controlA spacecraft has to have the right attitude, or orientation, to point cameras and antennas at targets on Earth. For attitude control, rockets or other devices rotate it around its center of mass. More, rockets or other devices rotateA rotating object’s spin rate. We use the right-hand rule to determine its direction. More it around its center of mass. More uses actuators which require continuous feedback and adjustment. This type of attitudeThe job of the attitude determination and control subsystem (ADCS) is to keep its spacecraft pointed in the right direction. More controlA spacecraft has to […]

TSTI Admin No Comments March 30, 2026

active thermal control

A method to maintain a spacecraft’s internal temperatureA method to maintain a spacecraft’s internal temperature using a closed-loop control systemAn assembly of devices that receive inputs, decide to change the plant conditions, act to change the plant, measure the plant outputs, and adjust the inputs to improve the outputs. More to measure current temperatureA method to maintain a spacecraft's internal temperature using a closed-loop control system to measure current temperature and adjust inputs, outputs and internal heat flow. It requires a working fluid, heaters, pumps, or other mechanical devices. More and adjust inputs, outputs and internal heat flow. It requires a working fluidA method to maintain a spacecraft's internal temperature using a closed-loop control system to measure current temperature and adjust inputs, outputs and internal heat flow. It requires a working fluid, heaters, pumps, or other mechanical devices. More, heaters, pumps, or other mechanicalA method to maintain a spacecraft's internal temperature using a closed-loop control system to measure current temperature and adjust inputs, outputs and internal heat flow. It requires a working fluid, heaters, pumps, or other mechanical devices. More devices. More using a closed-loop controlThe job of the attitude determination and control subsystem (ADCS) is to keep its spacecraft pointed in the right direction. More systemAn assembly of devices that receive inputs, […]

TSTI Admin No Comments March 30, 2026

actuator

The part of a controlThe job of the attitude determination and control subsystemThe job of the attitude determination and control subsystem (ADCS) is to keep its spacecraft pointed in the right direction. More (ADCS) is to keep its spacecraft pointed in the right direction. More system that actively changes its currentWe define current,i, as the rate at which charges flow through a given area, such as the cross section of a wire. The unit for current is amperes (amps), which equals the charges flowing per second. More state. For example, a rocketA fluid-dynamics concept that says as low-velocity gases pass into the converging part of a nozzle, they accelerate to the speed of sound at the narrowest section (throat). Then, after they pass through the throat, they expand and accelerate to supersonic speeds. This principle is the basis for creating thrust in a thermodynamic rocket. More is a type of actuatorThis type of spacecraft attitude controlA spacecraft has to have the right attitude, or orientation, to point cameras and antennas at targets on Earth. For attitude control, rockets or other devices rotate it around its center of mass. More uses actuators which require continuous feedback and adjustment. This […]

TSTI Admin No Comments March 30, 2026

acute dosages

High-level, short-term radiationHigh-level, short-term radiation exposure, causing more damage to human tissue than the same level spread over a longer time. More exposureHigh-level, short-term radiationHigh-level, short-term radiation exposure, causing more damage to human tissue than the same level spread over a longer time. More exposureHigh-level, short-term radiation exposure, causing more damage to human tissue than the same level spread over a longer time. More, causing more damage to human tissue than the same level spread over a longer timeThe time between successive passages of the Sun overhead, which is from noon one day to noon the next day. Because Earth’s orbit around the Sun is slightly elliptical, this time varies slightly during a year. More. More, causing more damage to human tissue than the same level spread over a […]