A coronal cloud is the cloud of hot plasma gas surrounding a coronal mass ejection. It is a cloud, or cloud-like, natural astronomical entity, composed of plasmas and usually associated with a star or other astronomical object where the temperature is such that X-rays are emitted. It is usually made up of protons and electrons. When a coronal mass ejection occurs at the Earth’s Sun, it is the coronal cloud that usually reaches Earth and causes damage to electrical equipment and space satellites, not the ejection or flares itself. The damage is mostly the result of the high amount of electricity moving through the atmosphere. “Coronal cloud” prominences appear to form as bright knots of mass condensing out of the corona while some of their mass also continuously drains down along curved streamers to the chromosphere.
A coronal cloud is released when a solar flare becomes a coronal mass ejection; the coronal cloud often contains more radioactive particles than the mass ejection itself. Coronae are caused by the diffraction of light from the light source (Sun or Moon), passing through the mist, fog, or thin cloud composed of very small water or ice particles. While small coronal clouds are above the photosphere of many different visual spectral type stars, others occupy parts of the interstellar medium (ISM), extending sometimes millions of kilometers into space, or thousands of light-years, depending on the size of the associated object such as a galaxy. A coronal mass ejection occurs when a solar flare becomes so hot that it snaps and breaks in two, becoming a “rope” of heat and magnetism that stretches between two sunspots. The corona can be as much as 15° in diameter and may shrink or swell as different clouds pass across the Sun or Moon.
The resulting coronal mass ejection can be compared to a horseshoe magnet, the sunspots being the poles, and the oscillating magnetic connector the handle. Sometimes, coronae seen in clouds appear distorted because of particle size differences in various parts of the clouds. Coronal mass ejections typically do not last very long, because they cool down as the coronal cloud of gas is released and begins to hurtle away from the Sun. The sun’s dynamic upper atmosphere. It is filled with plasma, whose movements are governed by the tangle of magnetic fields surrounding the sun. The plasma itself is a cloud of protons and electrons carried aloft by the solar wind. Distorted coronae with small radii may also be observed around the Moon because, except when full, the Moon is not an asymmetric light source.
