Thermosphere Facts: The Hottest Layer Of The Atmosphere

The thermosphere is the fourth layer from Earth's surface.

Being the fourth layer from Earth's atmosphere, it is situated between the mesosphere and exosphere. It is estimated to be approximately 310-621 mi (500-1000 km) away from our planet.

The thermosphere is the fourth of five layers and is situated right above the mesosphere. Extending up to a distance between 310-621 mi (500-1000 km), the layer is adjacent to the exosphere. The exosphere is the last layer of Earth's atmosphere.

Space is considered to exist from the exosphere. So, we can say that the thermosphere is technically the last layer of Earth's atmosphere that does not touch space.

The thermosphere is considered to be the hottest layer because of the radiation of the sun. Air molecules absorb direct rays from the sun which increases the thermosphere's temperature. The temperature is observed to be comparatively cooler at night, than during the day.

The thermosphere protects Earth's surface from harmful radiations like UV and X-ray radiations by absorbing them. As previously stated, this results in increasing temperatures within this layer.

The ionosphere, situated within the interior of the thermosphere, helps reflect waves. This helps in the transmission of radio frequencies and communications. Due to ionization, charged particles like atoms and ions are present here, along with other gas molecules.

The Thermosphere's Significance

As we know, the thermosphere is the last layer protecting Earth before its exposure to space via the exosphere. So, this layer not only protects Earth from various elements and situations but also protects the three underlying layers of the atmosphere.

Hence, the significance of this layer is immense and is known to be the biggest contributor to the exploration of space.

The major significance of the thermosphere is the space communication made possible. Apart from that fact, we must also note the absorption of radiation and the rise in heat in this layer.

The solar radiation that reaches this layer includes X-ray radiation, UV radiation, and gamma rays. These rays are observed to undergo the process of ionization along with other gas molecules.

The thermosphere also protects the Earth from coming into contact with meteorites. Due to air density and high temperatures at this layer, the meteorites disintegrate when they come in contact with the air in this layer.

The thermosphere also plays an important role in radio transmissions. The interior layer of the thermosphere, the ionosphere, reflects radio waves that help important communication lines travel.

Mesosphere Vs. Thermosphere

There are significant differences and similarities between the mesosphere and thermosphere. Both layers protect Earth's atmosphere but serve different purposes. Along with their purposes, the characteristics of these layers are quite distinctive and different from each other.

As we know, there are several atmospheric layers above the Earth's surface. The mesosphere is the third layer, whereas the thermosphere is the fourth layer. The mesosphere is comparatively hotter. The mesosphere lies right above the stratosphere, while the thermosphere lies right above the mesosphere.

In terms of distance, the mesosphere extends up to 49.7 mi (80 km) from Earth's surface, while the thermosphere extends up to around 310 mi (500 km). The temperatures decrease in the mesosphere with increasing altitudes. The thermospheric layer's temperatures increase with increasing altitude.

Thermosphere Temperature

The range of temperatures within the thermosphere is one of the major and most interesting thermosphere facts. As we know, the temperature in this zone is affected by exterior factors that are observed to be increasing. This increases the overall temperature on Earth.

The term thermosphere is a Greek word where 'Thermo' means heat. The temperature of the thermosphere is widely affected and influenced by solar activity and altitude.

With an increase in altitude, the temperature seems to increase within the layer. The upper part of the thermosphere has been recorded to have higher temperatures.

The heat in this layer can increase up to 3632 F (2000 C). As previously mentioned, the temperature in this zone is influenced by solar activity.

Researchers have claimed that the temperature is much higher during the daytime than at nighttime. So we can conclude that when the sun is active the temperature is high and in the absence of the sun, the air can be comparatively cooler within the thermosphere.

Thermosphere's Constituents

The layers above Earth's atmosphere are made up of gases. The air in these layers consists of numerous gases and traditions, especially the thermosphere. As we know, the radiation of the sun, as well as radioactive waves, is absorbed by the layer.

If we break down the components of the thermosphere, it consists of gases like oxygen, helium, and nitrogen. The air in the mesospheric zone is comprised of 80% of nitrogen and 20% oxygen molecules.

The air in the thermosphere is comparatively denser than other layers and approximately has an air density of around 56-254 mi (91- 410 km).

Apart from gases, radiation like ultraviolet radiation, X-ray radiation, and gamma rays, make the zone hotter. Due to the ionization of the molecules, charged ions and atoms are also present within the thermosphere.

FAQs

Which layer above Earth's surface is considered the hottest layer?

The thermosphere is considered to be the hottest layer in comparison to the other five.

What is the thermosphere?

The thermosphere is the fifth layer that is situated above the Earth's surface.

What can you find in the thermosphere?

Similar to Earth's surface, gases like oxygen and nitrogen can be found in the thermosphere. But unlike Earth's surface, UV, X-ray, and gamma radiations can be found within the thermosphere as well.

What important layer exists in the thermosphere?

The ionosphere is an extremely important part of the thermosphere. It is situated towards the interior part of the layer.

How does the thermosphere help with radio transmissions?

The ionosphere is present within the thermosphere. It helps reflect waves to the Earth. This reflection helps communications and radio transmissions travel.

What is the difference between the ionosphere and thermosphere?

The ionosphere is considered to be a part of the Earth's atmosphere. It extends approximately from an altitude of 31-310 mi (50 to 500 km). The thermosphere is a part of five layers that are present between the mesosphere and the exosphere. The thermosphere absorbs many radiations like UV rays and protects the Earth.