Atmospheric Waves Experiment (AWE)

About Atmospheric Waves Experiment (AWE)

• It is a first-of-its-kind NASA experimental attempt aimed at studying the interactions between terrestrial and Space weather.
• It is planned under NASA’s Heliophysics Explorers Program, this mission will study the links between how waves in the lower layers of the atmosphere impact the upper atmosphere, and thus, Space weather.
• It will be launched and mounted on the exterior of the Earth-orbiting International Space Station (ISS).
• From the vantage point, it will look down at the Earth and record the colourful light bands, commonly known as airglow.
• The new NASA mission will try to understand the combination of forces that drive the Space weather in the upper atmosphere.
• It will measure the airglow at mesopause (about 85 to 87 km above the Earth’s surface), where the atmospheric temperatures dip to minus 100 degrees Celsius.
• At this altitude, it is possible to capture the faint airglow in the infrared bandwidth, which appears the brightest enabling easy detection.
• It will be able to resolve waves at finer horizontal scales than what satellites can usually see at those altitudes, which is part of what makes the mission unique.
• The health of the ionosphere, whose lower layers sit at the edge of Space, is important for maintaining seamless communication.

What will NASA’S AWE do?

• It will perform focused mapping of the colourful airglows in the Earth’s atmosphere.
• Onboard AWE is an Advanced Mesospheric Temperature Mapper (ATMT), an instrument that will scan or map the mesopause (a region between the mesosphere and thermosphere).
• Using the four identical telescopes comprising an imaging radiometer, scientists hope to obtain the brightness of light at specific wavelengths. 
• This information can then be converted into a temperature map, which could reveal the airglow movement and ultimately, give clues on their role in the upper atmosphere and Space weather.

What is air glow?

• It is a faint luminescence of Earth’s upper atmosphere that is caused by air molecules’ and atoms’ selective absorption of solar ultraviolet and X-radiation.
• Most of the airglow emanates from the region about 50 to 300 km above the surface of Earth, with the brightest area concentrated at altitudes around 97 km.

Q1) What Is mesopause?

The mesopause is the point of minimum temperature at the boundary between the mesosphere and the thermosphere atmospheric regions. Due to the lack of solar heating and very strong radiative cooling from carbon dioxide, the mesosphere is the coldest region on Earth with temperatures as low as -100 °C (-148 °F or 173 K).

Source: How a NASA experiment will study ‘airglow’ to understand Space weather and why it matters