When astronauts in space look back toward Earth, they see greenish and reddish bands of light glowing softly in the dark sky. Called airglow, this light is caused by high-energy (ultraviolet and extra ultraviolet) radiation from the Sun that collides with the atoms and molecules of the upper atmosphere, over 40 miles above the surface of the Earth. These atoms and molecules get energy from the Sun's radiation, then re-emit (give off) the energy as light. Oxygen emits strong red and green light, and sodium gives off yellow light.

Airglow is present around the clock because the atmosphere is always interacting with radiation from the Sun, but during the day and twilight (dawn or evening), the Suns light is much brighter and we dont notice the airglow. Nighttime airglow can sometimes be bright enough to light the ground below, especially at high latitudes near the poles.

When there is a storm on the Sun and it hurls an extra blast of energetic particles toward Earth, we can have a spectacular light show‹the aurora. Called the aurora borealis, or Northern Lights in the Northern Hemisphere, and the aurora australis, or Southern Lights in the Southern Hemisphere, they are some of the most spectacular visions seen in the night sky.

Radio signals can be sent over great distances through the ionosphere, which starts about 35 miles (56 km) above the EarthÁs surface and extends up to about 500 miles (805 km). Storms on the Sun that send lots of energetic particles to the Earth and cause aurora can distort the ionosphere and interrupt our communications. Scientists at HAARP recreate, on a small scale, what happens when the atmosphere is excited by the Sun as energy.

Artificial Air Glow

When HAARP was used to excite a section of the ionosphere on several days in 2000, 2001, and 2002, researcher Elizabeth Gerken, a graduate student at Stanford University in California, was there. She and her fellow scientists watched the airglow created in the ionosphere through a telescope that has a special electronic camera called a charge-coupled device, or CCD. Red or green glass filters were placed in front of the cameraÁs lens to allow it to ËseeÓ only certain types of light. The cameraÁs shutter was kept open for 30 seconds so it could image faint glows that are invisible to the human eye. The camera sends digital pictures directly to a computer for processing into images that Elizabeth can then analyze. By studying how the ionosphere reacts to the experiments, scientists can begin to understand how it behaves during natural airglow and aurora.

A circumhorizon arc is one of the rarest halos one can witness. First. it requires a very high sun angle of approximately 58° or higher. A sun angle this high can only occur at northern latitudes during a small portion of the year centered around the summer solstice. Solar elevations of 58° or higher in Spokane are achieved in a small window beginning in May to the first week in August. Even in this window, the sun angle only exceeds this lofty elevation for a mere hour or so in May and August to around three hours near the summer solstice (June 21st).

Originally posted by MrPenny
reply to post by kdial1

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Now explain how that article supports or contributes to your thesis that HAARP testing caused the China earthquake. Simply dumping lengthy cut and pastes from external sources is not a proper research technique.

Its caused when similiar sized water or ice droplets in clouds, diffract sunlight giving the cloud brilliant rainbow colours. It occurs in random patches and/ or at the edge of forming cloud structures. The clouds it occurs in are altocumulus, cirrocumulus and very frequently in lenticular clouds (type of altocumulus)