APOD: Blue Sun Bursting (2013 May 20)

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Expand view Topic review: APOD: Blue Sun Bursting (2013 May 20)

Re: APOD: Blue Sun Bursting (2013 May 20)

by Anthony Barreiro » Mon May 20, 2013 10:53 pm

Chris Peterson wrote:
Anthony Barreiro wrote:Why are sunspots bright in CaK while the surrounding regions are dark in CaK?
blueberrysun_friedman_960_i.jpg
They aren't. The image has been inverted. This is what the Sun actually looks like in singly ionized calcium- the sunspots are cooler and darker, and the surrounds are hotter and brighter, pretty much as we'd expect.
:facepalm: Thanks.

Re: APOD: Blue Sun Bursting (2013 May 20)

by Boomer12k » Mon May 20, 2013 10:18 pm

Looks like a grumpy smiley face....maybe why he is "BLUE"???

An interesting view of the sun...does this picture tell us anything about the Chromosphere?

:---[===] *

Re: APOD: Blue Sun Bursting (2013 May 20)

by Chris Peterson » Mon May 20, 2013 8:22 pm

Anthony Barreiro wrote:Why are sunspots bright in CaK while the surrounding regions are dark in CaK?
blueberrysun_friedman_960_i.jpg
They aren't. The image has been inverted. This is what the Sun actually looks like in singly ionized calcium- the sunspots are cooler and darker, and the surrounds are hotter and brighter, pretty much as we'd expect.

Re: APOD: Blue Sun Bursting (2013 May 20)

by Anthony Barreiro » Mon May 20, 2013 8:01 pm

APOD Robot wrote: ... This solar depiction is actually scientifically illuminating as a level of the Sun's chromosphere appears quite prominent, showing a crackly textured surface, cool sunspots appearing distinctly bright, and surrounding hot active regions appearing distinctly dark. ...
Why are sunspots bright in CaK while the surrounding regions are dark in CaK?

Re: APOD: Blue Sun Bursting (2013 May 20)

by MargaritaMc » Mon May 20, 2013 6:46 pm

Image
Thank you very much, gentlemen.
Margarita

Re: APOD: Blue Sun Bursting (2013 May 20)

by Chris Peterson » Mon May 20, 2013 6:15 pm

MargaritaMc wrote:Following up links and generally reading around the subject of today's Apod, I read this:

http://en.wikipedia.org/wiki/Chromosphere
Whilst the photosphere has an absorption line spectrum, the chromosphere's spectrum is dominated by emission lines.
Can anyone explain to me how the spectrum of one is taken separately from the other? To me this seems impossible - but, clearly, it is not!
The chromosphere is a tenuous gas layer above the photosphere, and can be observed without interference from the photosphere from the Earth's surface during solar eclipses, and from space with occulting optics which block the solar disc. We always see the photosphere through the chromosphere, but the difference in brightness is many orders of magnitude, which effectively makes the chromosphere invisible (except by using very narrow band filters tuned to one of the emission lines you reference).

Re: APOD: Blue Sun Bursting (2013 May 20)

by neufer » Mon May 20, 2013 6:13 pm

This program shows the intensity of spectral lines for various temperature stars:

Stellar Spectroscopy Interactive

The calcium H & K lines hit a minimum at temperature: 5500 K.

For temperatures colder than 5500 K the calcium H & K lines turn into bright emission lines
in spite of the fact that there is no indication of the switchover in this particular program.


http://spiff.rit.edu/classes/phys230/le ... nterp.html

Re: APOD: Blue Sun Bursting (2013 May 20)

by MargaritaMc » Mon May 20, 2013 5:27 pm

I'm undoubtedly being dense, but I don't really get what you are explaining, Art. But thanks anyway.

I am in process of reading Kaler's The Spectra of Stars* and probably need to revisit your explanation once I've begun thoroughly to comprehend what Kaler says.

Margarita
* 'Stars and their Spectra'

Re: APOD: Blue Sun Bursting (2013 May 20)

by neufer » Mon May 20, 2013 4:52 pm

MargaritaMc wrote:
Following up links and generally reading around the subject of today's Apod, I read this:

http://en.wikipedia.org/wiki/Chromosphere
Whilst the photosphere has an absorption line spectrum, the chromosphere's spectrum is dominated by emission lines.
Can anyone explain to me how the spectrum of one is taken separately from the other? To me this seems impossible - but, clearly, it is not!
http://en.wikipedia.org/wiki/Calcium#H_and_K_lines wrote: H and K singly ionized calcium lines

<<Visible spectra of many stars, including the Sun, exhibit strong absorption lines of singly ionized calcium. Prominent among these are the H-line at 3968.5 Å and the K line at 3933.7 Å of singly ionized calcium, or Ca II. For the Sun and stars with low temperatures, the prominence of the H and K lines can be an indication of strong magnetic activity in the chromosphere. Measurement of periodic variations of these active regions can also be used to deduce the rotation periods of these stars.>>

Re: APOD: Blue Sun Bursting (2013 May 20)

by MargaritaMc » Mon May 20, 2013 4:38 pm

Following up links and generally reading around the subject of today's Apod, I read this:

http://en.wikipedia.org/wiki/Chromosphere
Whilst the photosphere has an absorption line spectrum, the chromosphere's spectrum is dominated by emission lines.
Can anyone explain to me how the spectrum of one is taken separately from the other? To me this seems impossible - but, clearly, it is not!

Margarita

Re: APOD: Blue Sun Bursting (2013 May 20)

by Lordcat Darkstar » Mon May 20, 2013 4:36 pm

Yummm ..blueberries and marshmellows 8-) and pluto can be a scoop of ice cream! Todays apod is making me hungry! :doughnut:

Re: APOD: Blue Sun Bursting (2013 May 20)

by emc » Mon May 20, 2013 2:30 pm

deathfleer wrote:
emc wrote:
deathfleer wrote:Can somebody answer me. Do these energetic particles push the Earth to correct orbit, equalizing the gravitational pull of the sun that drags it to fall into the blazing ball of fire?
Not only does the Sun make life possible here on Earth, it keeps the Earth from flying off into space. The Earth does not fall into the Sun due to the balance between the gravitational tug of the Sun and the Earth’s speed traveling through space (around the Sun). The Sun does “push” photons, flares, etc. our way and solar particles can affect certain aspects of Earth’s physics but they are not of sufficient mass to move the Earth.
thanks. It must be like a spinning top that is gradually slowing down, I thought it was like those floating things above a bonfire .
Well, according to evidence, the cosmos is expanding and may eventually “run down” but you don’t need to worry about that, the physics of the cosmos is way beyond our control. We will be healthier if we only worry about things we can do something about. Besides, the "running down" could be more than billions and billions and billions of years away.

Regarding those floating things above a bonfire… You could think of Earth as a marshmallow basking in the Sun’s output (fire) wherein you have an analogy that you may be looking for. The Sun’s particles (bonfire ambers) can hit or fly around the Earth (marshmallow). Fortunately, we are at the optimum position in space to benefit from the Sun (bonfire) such that we are not under or over cooked. And since we rotate every 24 hours, we also benefit from the variations in light/dark and heat/cold making for a perfect marshmallow!

Re: APOD: Blue Sun Bursting (2013 May 20)

by neufer » Mon May 20, 2013 1:54 pm

Click to play embedded YouTube video.
emc wrote:
FLPhotoCatcher wrote:
What are the sunspot-sized blue areas surrounded by, sometimes faint, dark (hot) 'cracks'?
I don’t know... and not intending to be disrespectful but your question reminded me of a joke…

What is the white stuff in bird poop?
More bird poop.

Re: APOD: Blue Sun Bursting (2013 May 20)

by deathfleer » Mon May 20, 2013 1:37 pm

emc wrote:
deathfleer wrote:Can somebody answer me. Do these energetic particles push the Earth to correct orbit, equalizing the gravitational pull of the sun that drags it to fall into the blazing ball of fire?
Not only does the Sun make life possible here on Earth, it keeps the Earth from flying off into space. The Earth does not fall into the Sun due to the balance between the gravitational tug of the Sun and the Earth’s speed traveling through space (around the Sun). The Sun does “push” photons, flares, etc. our way and solar particles can affect certain aspects of Earth’s physics but they are not of sufficient mass to move the Earth.
thanks. It must be like a spinning top that is gradually slowing down, I thought it was like those floating things above a bonfire .

Re: APOD: Blue Sun Bursting (2013 May 20)

by emc » Mon May 20, 2013 12:15 pm

FLPhotoCatcher wrote:What are the sunspot-sized blue areas surrounded by, sometimes faint, dark (hot) 'cracks'?
I don’t know... and not intending to be disrespectful but your question reminded me of a joke… What is the white stuff in bird poop?
More bird poop.

Re: APOD: Blue Sun Bursting (2013 May 20)

by emc » Mon May 20, 2013 12:06 pm

deathfleer wrote:Can somebody answer me. Do these energetic particles push the Earth to correct orbit, equalizing the gravitational pull of the sun that drags it to fall into the blazing ball of fire?
Not only does the Sun make life possible here on Earth, it keeps the Earth from flying off into space. The Earth does not fall into the Sun due to the balance between the gravitational tug of the Sun and the Earth’s speed traveling through space (around the Sun). The Sun does “push” photons, flares, etc. our way and solar particles can affect certain aspects of Earth’s physics but they are not of sufficient mass to move the Earth.

Re: APOD: Blue Sun Bursting (2013 May 20)

by neufer » Mon May 20, 2013 12:03 pm

deathfleer wrote:
Can somebody answer me. Do these energetic particles push the Earth to correct orbit, equalizing the gravitational pull of the sun that drags it to fall into the blazing ball of fire?
  • Not yet.

Re: APOD: Blue Sun Bursting (2013 May 20)

by deathfleer » Mon May 20, 2013 10:04 am

Can somebody answer me. Do these energetic particles push the Earth to correct orbit, equalizing the gravitational pull of the sun that drags it to fall into the blazing ball of fire?

Re: APOD: Blue Sun Bursting (2013 May 20)

by FLPhotoCatcher » Mon May 20, 2013 7:06 am

What are the sunspot-sized blue areas surrounded by, sometimes faint, dark (hot) 'cracks'?

APOD: Blue Sun Bursting (2013 May 20)

by APOD Robot » Mon May 20, 2013 4:06 am

Image Blue Sun Bursting

Explanation: Our Sun is not a giant blueberry. Our Sun can be made to appear similar to the diminutive fruit, however, by imaging it in a specific color of extreme violet light called CaK that is emitted by the very slight abundance of ionized Calcium in the Sun's atmosphere, and then false color-inverting the image. This solar depiction is actually scientifically illuminating as a level of the Sun's chromosphere appears quite prominent, showing a crackly textured surface, cool sunspots appearing distinctly bright, and surrounding hot active regions appearing distinctly dark. The Sun is currently near the maximum activity level in its 11 year cycle, and has emitted powerful flares over the past week. During times of high activity, streams of energetic particles from Sun may impact the Earth's magnetosphere and set off spectacular auroras.

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