Glossary A

The term Above ground level is used in aviation, atmospheric sciences and broadcasting, and is the height above ground level (AGL) measured with respect to the underlying ground surface.

The term Absolute humidity describes the water content of air and is expressed in either grams per cubic meter (m³) or grams per kilogram.

Deutsch: Absoluter Nullpunkt / Español: Cero absoluto / Português: Zero absoluto / Français: Zéro absolu / Italiano: Zero assoluto

Absolute zero is the theoretical lowest possible temperature where all molecular motion ceases. In the space industry, this concept is significant due to the extremely low temperatures encountered in space environments.

Deutsch: Absorption / Español: Absorbancia / Português: Absorvância / Français: Absorbance / Italiano: Assorbanza

Absorbance in the space industry refers to the measurement of how much radiation (typically light or other electromagnetic radiation) is absorbed by a material or substance when it passes through it. This concept is particularly relevant in designing and operating spacecraft and their instruments, where controlling and understanding light and radiation absorption is crucial.

Description

Absorbance is a fundamental optical property used to determine how materials interact with radiation. In space, where the environment is dominated by high levels of various forms of electromagnetic radiation—from visible light to ultraviolet (UV) and infrared (IR) radiation—understanding and managing absorbance is vital. Materials used in spacecraft must be chosen not only for their mechanical strength and light weight but also for their optical properties. For instance, materials with high absorbance for ultraviolet radiation are preferred for outer surfaces to protect sensitive components from UV degradation.

The application of absorbance in the space industry extends to the calibration of instruments and the design of optical systems that are part of spacecraft. Sensors that measure the absorbance of light at different wavelengths can be used to determine the composition of atmospheres and surfaces of planets and moons, or to detect distant celestial bodies.

Application Areas

1. Thermal management: Materials with specific absorbance properties are used to control the thermal environment within a spacecraft. High-absorbance materials can help in absorbing solar energy to maintain warmth, whereas low-absorbance materials can reflect solar radiation to keep the spacecraft cool.
2. Scientific instruments: Spectrophotometers and other devices that measure absorbance at various wavelengths are crucial in missions aimed at chemical and biological analysis of celestial bodies. For example, determining the presence of organic compounds on Mars or the composition of comets and asteroids.
3. Solar panels: The efficiency of solar panels depends on their ability to absorb sunlight; materials are selected based on their absorbance properties to maximize this efficiency.

Well-Known Examples

Spectrophotometric instruments aboard missions like the Mars Rover use absorbance to analyze soil and rock samples. By shining light on these samples and measuring the absorbed wavelengths, scientists can deduce the materials' composition. Another example is the Hubble Space Telescope, which uses sensors with precise absorbance characteristics to observe and analyze the light coming from distant galaxies, helping to determine their age, composition, and distance.

Treatment and Risks

While absorbance is a desirable property in many contexts, excessive absorption can pose risks:

• Overheating: Materials that absorb too much solar radiation can lead to overheating of spacecraft components, potentially damaging electronic systems.
• Radiation damage: Continuous exposure to high-energy radiation can degrade materials that have high absorbance in those frequencies, leading to a shorter operational life.

Careful selection of materials, combined with innovative design approaches, is necessary to mitigate these risks, ensuring that spacecraft can operate effectively over long durations in the harsh space environment.

Summary

In the space industry, absorbance plays a critical role in the design and function of spacecraft and their systems. From thermal management to scientific exploration, the ability to control and utilize absorbance properties ensures that missions can operate safely and efficiently, enabling successful exploration and study of the cosmos.

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English: Absorber / Deutsch: Absorber / Español: Absorbente / Português: Absorvedor / Français: Absorbeur / Italiano: Assorbitore /

An absorber is a device or material that absorbs a particular type of energy, such as sound waves, electromagnetic radiation, or heat.

In the aerospace context, absorption refers to the process by which a substance absorbs or takes in another substance. This can occur through chemical reactions, physical processes, or a combination of both.

Deutsch: Akademie / Español: Academia / Português: Academia / Français: Académie / Italiano: Accademia

Academy in the space industry context refers to an institution or organization dedicated to the education, training, and advancement of knowledge in the fields related to space science, engineering, and technology. These academies play a critical role in preparing the next generation of scientists, engineers, and astronauts, as well as advancing research and innovation in the sector.

Deutsch: Beschleunigung / Español: Aceleración / Português: Aceleração / Français: Accélération / Italiano: Accelerazione

Acceleration in the space industry context refers to the rate at which the velocity of an object changes over time. It is a fundamental concept in the physics of spaceflight and is crucial for maneuvering and propelling spacecraft through the various phases of a mission, from launch to orbital insertion and beyond.

In the dynamic and demanding field of aerospace, precise measurement of motion is essential for various applications, ranging from aircraft stability control to spacecraft navigation. One of the key tools used for this purpose is the accelerometer.

In the aerospace industry, "access" can refer to the ability to enter, approach, or use something, such as an aircraft, spacecraft, or facility. Access can be restricted or limited for various reasons, such as safety, security, or maintenance.

Deutsch: Zugang zum Luftraum im Kontext der Raumfahrtindustrie / Español: Acceso al espacio aéreo en el contexto de la industria espacial / Português: Acesso ao espaço aéreo no contexto da indústria espacial / Français: Accès à l'espace aérien dans le contexte de l'industrie spatiale / Italiano: Accesso allo spazio aereo nel contesto dell'industria spaziale

Access to airspace in the space industry context refers to the ability to utilize and traverse the Earth's atmosphere and outer space for purposes of launching and operating spacecraft, satellites, and other space-related technologies. This encompasses regulatory, legal, and logistical considerations that ensure safe and coordinated use of airspace by different entities, including governmental space agencies, private space companies, and international collaborators.

Deutsch: Zugang zu Einrichtungen / Español: Acceso a instalaciones / Português: Acesso a instalações / Français: Accès aux installations / Italiano: Accesso alle strutture

Access to facilities refers to the availability and ability to use various infrastructure and resources critical for space missions and research. This encompasses a wide range of facilities including launch sites, research labs, testing grounds, assembly areas, and communication networks.

An accident is an unintended, normally unwanted event that was not directly caused by humans.

Deutsch: Leistung / Español: Logro / Português: Realização / Français: Réussite / Italiano: Realizzazione

Accomplishment in the space industry context refers to the successful achievement of specific goals or milestones that contribute significantly to the field of space exploration, science, and technology. These accomplishments are often marked by breakthroughs in technology, mission successes, or substantial contributions to scientific knowledge.

Deutsch: Genauigkeit / Español: Precisión / Português: Precisão / Français: Précision / Italiano: Precisione /

Accuracy and precision are two measures of observational error. Accuracy is how close a given set of measurements (observations or readings) are to their true value, while precision is how close the measurements are to each other.

In the aerospace context, achievement refers to a significant accomplishment or progress in the field of aerospace technology and exploration.

Deutsch: Säurestärke / Español: Fuerza ácida / Português: Força ácida / Français: Force acide / Italiano: Forza dell'acido

Acid strength in the space industry context refers to the measure of an acid's ability to donate a proton or accept an electron pair in reactions. In space applications, understanding and controlling acid strength is important for material selection, corrosion control, and fuel processing, particularly in the operation and maintenance of spacecraft.

Deutsch: Säure-Base-Reaktion / Español: Reacción ácido-base / Português: Reação ácido-base / Français: Réaction acide-base / Italiano: Reazione acido-base

Acid-base reaction in the space industry context refers to a chemical reaction that involves the transfer of protons (H⁺ ions) between a proton donor (acid) and a proton acceptor (base). In the space industry, these reactions are significant for a variety of applications, from life support systems to energy storage and material processing.

Deutsch: Akustischer Absorber / Español: Absorbente acústico / Português: Absorvedor acústico / Français: Absorbeur acoustique / Italiano: Assorbitore acustico

Acoustic absorber in the space industry context refers to materials or systems designed to reduce sound pressure by absorbing sound energy, thus minimizing noise levels. This technology is crucial in spacecraft where controlling the acoustic environment is essential for crew comfort and equipment safety.

Deutsch: Akustische Lärmminderung / Español: Reducción de ruido acústico / Português: Redução de ruído acústico / Français: Réduction du bruit acoustique / Italiano: Riduzione del rumore acustico

Acoustic noise reduction refers to the methods and technologies used to minimize unwanted sound, particularly in environments where noise can affect the performance of equipment or the well-being of personnel. In the space industry, this involves reducing noise in spacecraft, launch vehicles, and ground facilities to protect sensitive instruments and ensure the safety and comfort of astronauts and engineers.