APOD: Sun and Prominence (2014 Mar 04)

Comments and questions about the APOD on the main view screen.
User avatar
APOD Robot
Otto Posterman
Posts: 2997
Joined: Fri Dec 04, 2009 3:27 am

APOD: Sun and Prominence (2014 Mar 04)

Postby APOD Robot » Tue Mar 04, 2014 5:13 am

Image Sun and Prominence

Explanation: Dramatic prominences can sometimes be seen looming just beyond the edge of the sun. Such was the case last week as a large prominence, visible above, highlighted a highly active recent Sun. A waving sea of hot gas is visible in the foreground chromosphere in great detail as it was imaged in one specific color of light emitted by hydrogen. A solar prominence is a cloud of solar gas held just above the surface by the Sun's magnetic field. The Earth, illustrated in the inset, is smaller than the prominence. Although very hot, prominences typically appear dark when viewed against the Sun, since they are slightly cooler than the photosphere below them. A quiescent prominence typically lasts about a month, and may erupt in a Coronal Mass Ejection (CME) expelling hot gas into the Solar System, some of which may strike the Earth and trigger auroras.

<< Previous APOD This Day in APOD Next APOD >>

Boomer12k
:---[===] *
Posts: 2090
Joined: Sun Apr 22, 2007 12:07 am

Re: APOD: Sun and Prominence (2014 Mar 04)

Postby Boomer12k » Tue Mar 04, 2014 6:52 am

Yup...their BIG!!!

Nice comparison...
:---[===] *

starsurfer
Stellar Cartographer
Posts: 2844
Joined: Thu Mar 15, 2012 7:25 pm

Re: APOD: Sun and Prominence (2014 Mar 04)

Postby starsurfer » Tue Mar 04, 2014 8:26 am

Hooray for Coronal Mass Ejections! :D :D :D

Czerno 1

Re: APOD: Sun and Prominence (2014 Mar 04)

Postby Czerno 1 » Tue Mar 04, 2014 10:45 am

Cool :=)
Comments say a prominence would appear less bright than the sun's surface.
I don't quite see it thusly looking at this photograph : is it a negative ?

User avatar
neufer
Vacationer at Tralfamadore
Posts: 14423
Joined: Mon Jan 21, 2008 1:57 pm
Location: Alexandria, Virginia

Re: APOD: Sun and Prominence (2014 Mar 04)

Postby neufer » Tue Mar 04, 2014 1:59 pm

Czerno 1 wrote:Cool :=)
Comments say a prominence would appear less bright than the sun's surface.
I don't quite see it thusly looking at this photograph : is it a negative ?

No. You are just comparing it against the dark background of space.

When compared against the solar surface like a sunspot it becomes a dark cool filament:
http://www.thesuntoday.org/overview/obj ... m-the-sun/ wrote:
_The Sun Today_ by C. Alex Young, Ph.D.

<<Sometimes magnetic field in the solar atmosphere holds up solar plasma from the chromosphere into the solar corona. The filaments are held up in a kind-of magnetic hammock. The relatively cool filament material appears dark when observed against the bright solar disk. Filaments can stretch far across the Sun measuring 100s of thousands of kilometers. The equivalent of 10 or more Earths lined up in a row. Prominences are really just the same thing as filaments only viewed from a different perspective. Filament are seen on the solar disk however filament are very high up in the solar atmosphere, way above the surface. So when a filament is on the edge of the Sun the filament sticks out with space instead of the solar surface behind it. This makes the filament very bright compared to the dark (cold) background of space. We call a filament viewed this way a prominence. They can be simple looped shaped object or very irregular with a complicated structure.>> More at:
http://www.thesuntoday.org/overview/obj ... m-the-sun/
Art Neuendorffer

User avatar
Chris Peterson
Abominable Snowman
Posts: 13283
Joined: Wed Jan 31, 2007 11:13 pm
Location: Guffey, Colorado, USA

Re: APOD: Sun and Prominence (2014 Mar 04)

Postby Chris Peterson » Tue Mar 04, 2014 3:17 pm

Czerno 1 wrote:Comments say a prominence would appear less bright than the sun's surface.
I don't quite see it thusly looking at this photograph : is it a negative ?

The difference in brightness isn't normally very large. In this case, we are seeing the prominence adjacent to the limb darkened edge, making the two have nearly identical average intensities. The difference would be more apparent if this were seen as a filament in a central section of the Sun.
Chris

*****************************************
Chris L Peterson
Cloudbait Observatory
http://www.cloudbait.com

User avatar
Ann
4725 Å
Posts: 8470
Joined: Sat May 29, 2010 5:33 am

Re: APOD: Sun and Prominence (2014 Mar 04)

Postby Ann » Tue Mar 04, 2014 3:34 pm

APOD Robot wrote:
Tomorrow's picture: colorful space chicken


Could it possibly be the Running Chicken Nebula? But which chicken?

Ann
Color Commentator

User avatar
Psnarf
Science Officer
Posts: 282
Joined: Fri Feb 26, 2010 6:19 pm

Re: APOD: Sun and Prominence (2014 Mar 04)

Postby Psnarf » Tue Mar 04, 2014 4:28 pm

I did not know that those beasties were above the solar surface in the photosphere, like a layer of clouds, or that different gasses could change layers. The granulation around a sunspot in the photosphere suggests that there may be another layer below that. Somewhere among the related sites listed below describes how the filaments are frozen to magnetic field lines.

Dr. Feynman suggests that magnetic fields are streams of low-energy photons. I guess Faraday was right when he thought of magnetic field lines of force indicating the direction and strength of the magnetic field at a given point. If you sprinkle iron filings on a paper over a magnet, they line up along those field lines; if you repeat the process, taking a photograph of the iron filings each time, would the lines pretty-much line up, or would they trace a different path each time. Sans a bar magnet and filings, I can only wonder. [Disclaimer: homophone of Zanzibar unintentional and not meant to irritate the residents of Tanzania]

http://sdo.gsfc.nasa.gov/mission/instruments.php
http://sdo.gsfc.nasa.gov/data/
http://aia.lmsal.com/public/CSR.htm

User avatar
Psnarf
Science Officer
Posts: 282
Joined: Fri Feb 26, 2010 6:19 pm

Re: APOD: Sun and Prominence (2014 Mar 04)

Postby Psnarf » Tue Mar 04, 2014 4:30 pm

[Delete this before reading it.] Why did the space chicken cross the nebula?

wroberts

Re: APOD: Sun and Prominence (2014 Mar 04)

Postby wroberts » Tue Mar 04, 2014 4:33 pm

The inset photo of the earth should have been delineated more prominently. Less knowledgeable viewers or those who fail to read the caption might incorrectly assume this is an actual photo of the Sun and Earth rather than a composite.

User avatar
Chris Peterson
Abominable Snowman
Posts: 13283
Joined: Wed Jan 31, 2007 11:13 pm
Location: Guffey, Colorado, USA

Re: APOD: Sun and Prominence (2014 Mar 04)

Postby Chris Peterson » Tue Mar 04, 2014 4:36 pm

Psnarf wrote:Dr. Feynman suggests that magnetic fields are streams of low-energy photons.

That's not the case. Feynman utilized the concept of virtual photons as force carriers describing magnetic fields. Magnetic fields are not created by streams of photons, and I don't think Feynman ever made that suggestion.
Chris

*****************************************
Chris L Peterson
Cloudbait Observatory
http://www.cloudbait.com

User avatar
Chris Peterson
Abominable Snowman
Posts: 13283
Joined: Wed Jan 31, 2007 11:13 pm
Location: Guffey, Colorado, USA

Re: APOD: Sun and Prominence (2014 Mar 04)

Postby Chris Peterson » Tue Mar 04, 2014 4:39 pm

wroberts wrote:The inset photo of the earth should have been delineated more prominently. Less knowledgeable viewers or those who fail to read the caption might incorrectly assume this is an actual photo of the Sun and Earth rather than a composite.

Personally, I have very little sympathy for people who misunderstand images because they're too lazy to read the caption. It is much easier to get a sense of scale without any delineation. (And I think the fact that one image is color and the other B&W gives a bit of a clue, as well.)
Chris

*****************************************
Chris L Peterson
Cloudbait Observatory
http://www.cloudbait.com

User avatar
Anthony Barreiro
Turtles all the way down
Posts: 793
Joined: Wed May 11, 2011 7:09 pm
Location: San Francisco, California, Turtle Island

Re: APOD: Sun and Prominence (2014 Mar 04)

Postby Anthony Barreiro » Tue Mar 04, 2014 8:01 pm

Chris Peterson wrote:
wroberts wrote:The inset photo of the earth should have been delineated more prominently. Less knowledgeable viewers or those who fail to read the caption might incorrectly assume this is an actual photo of the Sun and Earth rather than a composite.

Personally, I have very little sympathy for people who misunderstand images because they're too lazy to read the caption. It is much easier to get a sense of scale without any delineation. (And I think the fact that one image is color and the other B&W gives a bit of a clue, as well.)

But there should be a prominent disclaimer: if the Earth were at this distance from the Sun, it would no longer be in the Sun's habitable zone, and would no longer have oceans or clouds. :lol2:
May all beings be happy, peaceful, and free.

User avatar
LocalColor
Science Officer
Posts: 266
Joined: Sat Mar 31, 2012 9:11 pm
Location: Central Idaho, USA

Re: APOD: Sun and Prominence (2014 Mar 04)

Postby LocalColor » Tue Mar 04, 2014 11:10 pm

A stunning and very informative image.

User avatar
Chris Peterson
Abominable Snowman
Posts: 13283
Joined: Wed Jan 31, 2007 11:13 pm
Location: Guffey, Colorado, USA

Re: APOD: Sun and Prominence (2014 Mar 04)

Postby Chris Peterson » Wed Mar 05, 2014 12:05 am

Anthony Barreiro wrote:But there should be a prominent disclaimer: if the Earth were at this distance from the Sun, it would no longer be in the Sun's habitable zone, and would no longer have oceans or clouds.

Nonsense. It's in exactly the middle of the habitable zone for plasma fish.
Chris

*****************************************
Chris L Peterson
Cloudbait Observatory
http://www.cloudbait.com

User avatar
Beyond
500 Gigaderps
Posts: 6889
Joined: Tue Aug 04, 2009 11:09 am
Location: BEYONDER LAND

Re: APOD: Sun and Prominence (2014 Mar 04)

Postby Beyond » Wed Mar 05, 2014 1:02 am

:)))))))))))))))))))))
To find the Truth, you must go Beyond.

User avatar
Anthony Barreiro
Turtles all the way down
Posts: 793
Joined: Wed May 11, 2011 7:09 pm
Location: San Francisco, California, Turtle Island

Re: APOD: Sun and Prominence (2014 Mar 04)

Postby Anthony Barreiro » Wed Mar 05, 2014 3:40 am

Chris Peterson wrote:
Anthony Barreiro wrote:But there should be a prominent disclaimer: if the Earth were at this distance from the Sun, it would no longer be in the Sun's habitable zone, and would no longer have oceans or clouds.

Nonsense. It's in exactly the middle of the habitable zone for plasma fish.

Oh yes, of course. I read about them in The Journal of Exobiology.
May all beings be happy, peaceful, and free.

Czerno 1

Re: APOD: Sun and Prominence (2014 Mar 04)

Postby Czerno 1 » Sat Mar 08, 2014 10:36 am

Belated thanks (Neufer, Chris!) for explanations re. relative brilliance,
and the fact that prominences and filaments are the same phenomenon,
just different views ! Very instructive...


Return to “The Bridge: Discuss an Astronomy Picture of the Day”

Who is online

Users browsing this forum: Ahrefs [Bot], neufer and 4 guests