Solar prominence

Protuberance is also a technical term from the poultry and called there a strong increase in the cranial plates of chicken birds. Protuberance is also called in gear manufacturing cutting free of the tooth root with special tooth cutters. This is done so that must not be touched with subsequent scraping or grinding of the tooth base.

Prominences are violent matter flows on the sun, which can be observed at the solar limb as matte luminous arcs. In smaller dimensions may also occur within the solar disk and are observed in the red H -alpha light. Do they appear as dark, thread-like structures on the solar disk, as they are called filaments.

Species

There are two types of prominences:

• Quiescent prominences are structures whose shape is often months hardly changed. They often occur near sunspots and are produced by strong magnetic fields and kept in shape. This matter flows along the magnetic field lines above the solar surface. It cools and appears darker than the surrounding area. Any failures in the magnetic material falls back onto the surface. The luminous phenomena that occur are also known as Hyder flares.

• Eruptive prominences ( coronal mass ejections, also called active prominences, often solar flare in general ) are phenomena that only last a few minutes or hours. This matter with up to 1,000 km / s is thrown by the sun. They sometimes arise from quiescent prominences which adopt following the outbreak usually return to their old form.

Particularly strong solar flares occur about every 11 years. During this time, are observed in the polar regions of the earth more often than usual auroras.

Formation

The emergence of a protuberance is based on magnetic Rekonnexionen in the chromosphere of the Sun. Similar to the sunspot cycle with a length of 11 or 22 years, it is also observed in prominences a cyclic variability of the indicators over a period of several years. Solar activity is very strongly correlated with the appearance of protuberances.

Observation

The best way to observe at a total solar eclipse, in which they appear as large arches that extend far into space prominences. Often they have a length of several hundred thousand kilometers, heights up to 40,000 kms 5000 km thick. Particularly strong currents can also rising up over a million kilometers on the solar surface, the sheet can stand out and this throws the matter into space.

The observation of prominences was, until a few decades ago only during a solar eclipse possible because the luminosity of these eruptions is many times weaker than that of the photosphere. Since the invention of devices that generate a kind of artificial eclipse, observations and measurements are possible at any time. Examples are:

• Koronograf
• Protuberance spectroscope, and as a special scanner technology also
• Spektroheliograf to measure various layers of the sun
• Protuberanzenansatz and - telescope
• H-alpha telescope with an interference filter which transmits only the light of the ionized hydrogen.