The European Space Agency’s (ESA) deployment of its satellites and the ExoMars Trace Gas Orbiter (TGO) sensor to Mars has led to an exciting and unexpected discovery. For the first time, the Martian atmosphere has been observed to glow green in the visible light spectrum at night.

This effect is called an airglow, and it also occurs on Earth, but is slightly different from the northern lights known as the aurora borealis. On Earth, the night glow is created when two oxygen atoms react to form an ozone molecule, while the aurora borealis glow occurs when charged particles from the Sun collide with Earth’s magnetic field.

An airglow has been thought to exist on Mars for about 40 years and was first detected a decade ago by the European Space Agency’s Mars Express spacecraft, which spotted the infrared phenomenon. In 2020, the event was also observed in visible light using TGO during the day.

These new observations are interesting, especially for future missions to Mars. The airglow in the polar regions of Mars is so intense that it cannot be studied using simple and relatively inexpensive instruments.

Nocturnal airglow research on Mars is planned to continue as part of the TGO mission, as it will provide a better way to study the composition and dynamics of the planet’s upper atmosphere between 40 and 80 kilometers altitude. Our better understanding of the Martian atmosphere will contribute to the design of future missions to the Red Planet, either by building satellites that can withstand atmospheric drag or designing parachutes to help reduce the loads on the Martian surface.

Frequently Asked Questions:

What is nocturnal ventilation on Mars?

A nocturnal airglow is a phenomenon that occurs in the Martian atmosphere when two oxygen atoms form an ozone molecule about 31 miles (50 km) above the planet’s surface.

Are there similar phenomena on Earth?

Yes, there are similar phenomena on Earth, such as the northern lights called aurora borealis. However, the nocturnal wind on Mars is slightly different from the aurora in composition and causes.

What is the significance of studying airglow on Mars?

Studying the airglow helps understand the processes occurring in the Martian atmosphere, and provides scientists with insight into designing future missions to the Red Planet, including developing satellites capable of coping with various weather conditions and designing parachutes to help lower payloads to the Martian surface.