Everything about The Stellar Atmosphere totally explained
The
stellar atmosphere is the outer region of the volume of a
star, lying above the
stellar core,
radiation zone and
convection zone. It is divided into several regions of distinct character:
The
photosphere, which is the lowest and coolest part of the star's atmosphere is the part which we see.
Light escaping from the surface of the star stems from this region and passes through the higher layers. The photosphere of the
Sun has a temperature (
effective temperature) of about 5780
K.
Starspots, cool regions of disrupted
magnetic field lie on the photosphere.
Above the photosphere lies the
chromosphere. This part of the atmosphere first cools down and then starts to heat up to about 10 times the temperature of the photosphere.
Above the chromosphere lies the
transition region, where the temperature increases rapidly on a distance of only around 100 km. Beyond this region is the outermost part of the stellar atmosphere, the
corona, a tenuous but extremely hot (million K)
plasma. While all stars on the
main sequence feature transition regions and coronae, not all evolved stars do so. It seems that only some
giants, and very few
supergiants possess coronae. An unresolved problem in stellar
astrophysics is the question as to how exactly the corona can be heated to such high temperatures. The answer lies in
magnetic fields, but the exact mechanism remains unclear.
During a total
solar eclipse, the photosphere of the Sun is obscured, revealing the other layers of the atmosphere. Under these conditions, the chromosphere appears as a rough reddish ring, and the corona appears as a tufted halo.
Further Information
Get more info on 'Stellar Atmosphere'.
|
External Link Exchanges
Do you know how hard it is to get a link from a large encyclopaedia? Well we're different and will prove it. To get a link from us just add the following HTML to your site on a relevant page:
<a href="http://stellar_atmosphere.totallyexplained.com">Stellar atmosphere Totally Explained</a>
Then simply click through this link from your web page. Our crawlers will verify your link, extract the title of your web page and instantly add a link back to it. If you like you can remove the words Totally Explained and embed the link in article text.
As long as your link remains in place, we'll keep our link to you right here. Please play fair - our crawlers are watching. Your site must be closely related to this one's topic. Any kind of spamming, dubious practises or removing the link will result in your link from us being dropped and, potentially, your whole site being banned. |