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The photosphere of the Sun has an effective temperature of 5, 570 K yet its corona has an average temperature of 1 – 2 × 10 < sup > 6 </ sup > K. However, the hottest regions are 8 – 20 × 10 < sup > 6 </ sup > K. The high temperature of the corona shows that it is heated by something other than direct heat conduction from the photosphere.
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photosphere and Sun
* The umbra, within which the Moon completely covers the Sun ( more precisely, its photosphere ).
During partial eclipses most sunlight is blocked by the Moon passing in front of the Sun, but the uncovered parts of the photosphere have the same surface brightness as during a normal day.
Sunspots are temporary phenomena on the photosphere of the Sun that appear visibly as dark spots compared to surrounding regions.
Granules — the tops or upper visible sizes of convection cells, seen on the photosphere of the Sun.
These are caused by the convection in the upper photosphere of the Sun.
Granules on the photosphere of the Sun are the visible tops of convection cells in the photosphere, caused by convection of plasma in the photosphere.
The Sunspot Number ( SSN ) is the number of sunspots on the Sun's photosphere in visible light on the side of the Sun visible to an Earth observer.
The photosphere of the Sun, at a temperature of approximately 6000 K, emits radiation principally in the ( human -) visible portion of the electromagnetic spectrum.
With a temperature of 5870 kelvins, the photosphere of the Sun emits a very small proportion of radiation in the extreme ultraviolet ( EUV ) and above.
During a total solar eclipse, the photosphere of the Sun is obscured, revealing its atmosphere's other layers.
At any one time there are around 60, 000 to 70, 000 active spicules on the Sun ; an individual spicule typically reaches 3, 000-10, 000 km altitude above the photosphere.
The EIT wavelengths are of great interest to solar physicists because they are emitted by the very hot solar corona but not by the relatively cooler photosphere of the Sun ; this reveals structures in the corona that would otherwise be obscured by the brightness of the Sun itself.
Granules on the photosphere of the Sun are caused by convection currents ( thermal columns, Bénard cells ) of plasma within the Sun's convective zone.
The effective temperature of the photosphere is nearly 10, 000 K and the star has expanded to nearly five times the radius of the Sun.
:.</ ref > With the planet Mercury orbiting the Sun at approximately 0. 4 AU, Schedar's photosphere extends to roughly half the mercurial orbit.
The large area of the photosphere means that it is emitting about 1, 455 times as much energy as the Sun, even though the effective temperature is only 3, 795 K ( compared to 5, 778 K on the Sun ).
The radius of this star is more than three times the radius of the Sun, and the photosphere has an effective temperature of about 10, 000.
photosphere and has
If the star temperature has been determined by a majority of absorption lines, unusual absences or strengths of lines for a certain element may indicate an unusual chemical composition of the photosphere.
The Sun's photosphere has a temperature between 4500 and 6000 K ( with an effective temperature of 5777 K ) and a density of about 2 kg / m < sup > 3 </ sup >; other stars may have hotter or cooler photospheres.
The Sun's visible atmosphere has other layers above the photosphere: the 2, 000 kilometer-deep chromosphere ( typically observed by filtered light, for example H-alpha ) lies just between the photosphere and the much hotter but more tenuous corona.
Whilst the photosphere has an absorption line spectrum, the chromosphere's spectrum is dominated by emission lines.
This anomaly might be caused by a diffusion process that has transported some of the helium and heavier elements out of the photosphere and into a region below the star's convection zone.
At the light-emitting layer called the photosphere, it has a temperature of about 2, 800 K, which is low enough for chemical compounds to form and survive.
The Sun's photosphere has a temperature in the 5, 770 K to 5, 780 K range.
When Culla realizes he has been discovered he retreats to the instrument side of the ship and begins disabling the equipment that propels the sunship so that it will fall into the photosphere, taking all evidence of his deception with it.
* Sunspot-a region on the Sun's surface ( photosphere ) that is marked by a lower temperature than its surroundings and has intense magnetic activity, which inhibits convection, forming areas of low surface temperature.
However, because the orange giant is nearing the final stages of its evolution, the photosphere has expanded substantially, yielding a bolometric luminosity that is approximately 676L < sub >☉</ sub >< ref name =" NOTELUMINOSITY " group =" note ">
photosphere and effective
Sunspots are cooler than the rest of the photosphere, with effective temperatures of about 4000 ° C ( about 7000 ° F ).
The effective surface temperature of the star's photosphere is about 4, 000 K, giving it an orange hue.
The effective temperature of the star's photosphere is 4, 710 K, giving Epsilon Cygni an orange hue that is a characteristic of K-type stars.
The effective temperature of the photosphere is 18, 000 K, which gives the star a blue-white hue.
photosphere and temperature
The temperature of a star determines its spectral type via its effect on the physical properties of plasma in its photosphere.
Although they are at temperatures of roughly, the contrast with the surrounding material at about 5780 K ( 5500 ° C ) leaves them clearly visible as dark spots, as the luminous intensity of a heated black body ( closely approximated by the photosphere ) is a function of temperature to the fourth power.
The spectral class of a star is a designated class of a star describing the ionization of its photosphere ( what atomic excitations are most prominent in the light ), giving an objective measure of the photosphere's temperature.
This is causing the equator to bulge outward because of centrifugal effects, and, as a result, there is a variation of temperature across the star's photosphere that reaches a maximum at the poles.
Skylab measured the temperature ( solid curve ) and density ( dashed curve ) of the chromosphere between the thinner transition region and the lower photosphere ( darker orange ).
Its temperature at the top of photosphere is only about 4, 400 K, whilst at the top of chromosphere, some 2, 000 km higher, it reaches 25, 000 K. This is however the opposite of what we find in the photosphere, where the temperature drops with increasing height.
Observed starspots have a temperature which is in general 500 – 2000 Kelvin cooler than the stellar photosphere.
There also seems to be a relation between the spot temperature and the temperature for the stellar photosphere, indicating that starspots behave similarly for different types of stars ( observed in G-K dwarfs )
Beyond the photosphere lies a nebulous, high temperature region known as the corona.
photosphere and K
Solar plasma feeding these structures is heated from under 6000 K to well over 1 × 10 < sup > 6 </ sup > K from the photosphere, through the transition region, and into the corona.
Although there is a high level of noise in the radial velocity data due to magnetic activity in the star's photosphere, any periodicity caused by this magnetic activity is expected to show a strong correlation with variations in emission lines of ionized calcium ( the Ca II H and K lines ).
Temperature estimates of the photosphere of Wolf 359 range from 2, 500 K to 2, 900 K, which is sufficiently cool for equilibrium chemistry to occur.
0.107 seconds.