Look high and higher for the beautiful noctilucent clouds
With the intensity of the summer monsoon season here in Arizona, we look to the subject of meteorology and in particular, clouds.
We are used to seeing many types of clouds on any given day and some of these are very recognizable to us – the cotton-looking clouds we call cumulonimbus and the higher altitude clouds known as cirrus clouds.
To make all this better understood, we need to look and identify all the layers of the Earth’s atmosphere.
The lowest of all the parts of the atmosphere we call the troposphere. This layer of the atmosphere is most important to us as it contains the breathable oxygen and other life-supporting systems.
It reaches a height of some 10 miles above the planet.
Look at it this way: the breathable part of the Earth’s atmosphere is as thin as the skin on an apple if that was the size of the Earth.
From here, we visit the next layer, the stratosphere. This is a layer of the atmosphere up to about 31 miles above the ground layer. This is the region where most jet aircraft fly and the ozone layer of the planet also lies.
From here, we visit the mesosphere, a region of the atmosphere up to 53 miles above the planet. This is the layer in which we see most meteors “burn” up and the location of the strange noctilucent clouds, which we will visit soon.
The next layer is known as the thermosphere, up to 600 or more miles above us. It is the hottest portion of the atmosphere. It helps to filter out gamma and X-rays from hitting the surface.
Finally, the region known as the exosphere, where most satellites orbit Earth.
The highest clouds on Earth are those known as noctilucent clouds. A combination of meteor dust and water vapor, they glow at night in the summer skies of both hemispheres.
Here is what they look like.
These clouds appear to glow with an amazing sheen and are quite beautiful when observed.
First observed after the great 1883 Krakatoa explosion in 1885. These clouds are seen mostly in the summer months.
There may be an interesting connection with the increase in noctilucent clouds and the high number of rocket launches around the globe.
The water and chemicals in the exhaust plumes of rockets may be fueling the increase in the clouds.
Here are more details.
The clouds have been seen in many lower latitude observing sites and are quite beautiful in the dusk or predawn sky. They “light up” at these times as sunlight is streaming upwards well before and after sunset and sunrise.
With the summer and fall meteor showers to come, the sighting of the magical clouds is on the increase.
This also makes for a great photo opportunity for you on your vacations to locations which have open spaces and better views of the sky!
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