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APOD: Sunspot Loops in Ultraviolet (2011 Apr 10)

Posted: Sun Apr 10, 2011 4:06 am
by APOD Robot
Image Sunspot Loops in Ultraviolet

Explanation: It was a quiet day on the Sun. The above image shows, however, that even during off days the Sun's surface is a busy place. Shown in ultraviolet light, the relatively cool dark regions have temperatures of thousands of degrees Celsius. Large sunspot group AR 9169 from the last solar cycle is visible as the bright area near the horizon. The bright glowing gas flowing around the sunspots has a temperature of over one million degrees Celsius. The reason for the high temperatures is unknown but thought to be related to the rapidly changing magnetic field loops that channel solar plasma. Large sunspot group AR 9169 moved across the Sun during 2000 September and decayed in a few weeks.

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Re: APOD: Sunspot Loops in Ultraviolet (2011 Apr 10)

Posted: Sun Apr 10, 2011 1:23 pm
by neufer

Re: APOD: Sunspot Loops in Ultraviolet (2011 Apr 10)

Posted: Sun Apr 10, 2011 3:49 pm
by mexhunter
It is a fantastic image that brings us to the vagaries of our star.
Greetings
César

Re: APOD: Sunspot Loops in Ultraviolet (2011 Apr 10)

Posted: Sun Apr 10, 2011 5:05 pm
by biddie67
((grin)) Think of the problems we might have if the sun ejected "sun-sized froot loops" towards us rather than solar winds.

Our sun is so awesome and it isn't even near to being the monster that other suns/stars are.....

Re: APOD: Sunspot Loops in Ultraviolet (2011 Apr 10)

Posted: Sun Apr 10, 2011 5:17 pm
by Beyond
Hey neufer, is there REAL milk in the bowl??

Biddie67, if the sun ejected the right size "froot" loops at us just right, we could end up looking a lot like saturn. :mrgreen:

Re: APOD: Sunspot Loops in Ultraviolet (2011 Apr 10)

Posted: Sun Apr 10, 2011 5:18 pm
by nz1m
Howdy... sensational image today. Question: As the speed of light is "absolute." And "absolute zero" is, well, absolute. Is there an "absolute" high temperature?

Re: APOD: Sunspot Loops in Ultraviolet (2011 Apr 10)

Posted: Sun Apr 10, 2011 5:31 pm
by neufer
Beyond wrote:Hey neufer, is there REAL milk in the bowl??
So far as I can tell it is a $90 LED bowl lamp
for which you are to supply the milk, cereal & (possibly) spoon.

Every time you touch (or insert) the spoon the lamp turns on.

Re: APOD: Sunspot Loops in Ultraviolet (2011 Apr 10)

Posted: Sun Apr 10, 2011 7:43 pm
by Iphoneapod
It's unclear to me when the subject picture was taken. Does anyone have that information?

Re: APOD: Sunspot Loops in Ultraviolet (2011 Apr 10)

Posted: Sun Apr 10, 2011 7:43 pm
by Iphoneapod
It's unclear to me when the subject picture was taken. Does anyone have that information?

Re: APOD: Sunspot Loops in Ultraviolet (2011 Apr 10)

Posted: Sun Apr 10, 2011 7:54 pm
by neufer
Iphoneapod wrote:
It's unclear to me when the subject picture was taken. Does anyone have that information?
It wasn't recently.

http://apod.nasa.gov/apod/ap000925.html

Re: APOD: Sunspot Loops in Ultraviolet (2011 Apr 10)

Posted: Sun Apr 10, 2011 8:19 pm
by bystander
Iphoneapod wrote:It's unclear to me when the subject picture was taken. Does anyone have that information?
APOD Robot wrote:Large sunspot group AR 9169 moved across the Sun during 2000 September and decayed in a few weeks.
See also: APOD: Sunspot Loops in Ultraviolet (2002 May 8)

Re: APOD: Sunspot Loops in Ultraviolet (2011 Apr 10)

Posted: Sun Apr 10, 2011 10:16 pm
by NoelC
The size of that display is just awesome... Anything big enough to be pictured while also seeing significant curvature in the sun's surface... Wow.

Maybe it's just me, but I'd love to see something like this shown in a color closer to the real color. It would seem to me to communicate better that what's being pictured is off the high frequency end of the visible spectrum, instead of being akin to glowing coals...
VioletSun.jpg
-Noel

Re: APOD: Sunspot Loops in Ultraviolet (2011 Apr 10)

Posted: Mon Apr 11, 2011 1:12 pm
by neufer
http://www.universetoday.com/84747/video-dancing-spiral-magnetic-loops-on-the-sun/ wrote:
Click to play embedded YouTube video.
<<Cascades of spiraling magnetic loops observed in extreme ultraviolet light by Solar Dynamics Observatory danced and twisted above an active region on the Sun recently (April 3-5, 2011). These loops are charged particles spinning along the magnetic field lines. The bright active region was fairly strong and the activity persistent, though not explosive. At one point darker plasma can be seen being pulled back and forth across the region’s center.>>

Re: APOD: Sunspot Loops in Ultraviolet (2011 Apr 10)

Posted: Mon Apr 11, 2011 1:34 pm
by bystander
neufer wrote:
http://www.universetoday.com/84747/video-dancing-spiral-magnetic-loops-on-the-sun/ wrote:<<Cascades of spiraling magnetic loops observed in extreme ultraviolet light by Solar Dynamics Observatory danced and twisted above an active region on the Sun recently (April 3-5, 2011). These loops are charged particles spinning along the magnetic field lines. The bright active region was fairly strong and the activity persistent, though not explosive. At one point darker plasma can be seen being pulled back and forth across the region’s center.>>
SDO: Pick of the Week (2011 Apr 08) - Spiraling Active Region in Profile
http://asterisk.apod.com/viewtopic.php? ... 51#p146351

Re: APOD: Sunspot Loops in Ultraviolet (2011 Apr 10)

Posted: Mon Apr 11, 2011 6:53 pm
by nz1m
nz1m wrote:Howdy... sensational image today. Question: As the speed of light is "absolute." And "absolute zero" is, well, absolute. Is there an "absolute" high temperature?
OK... here's the real answer: http://www.pbs.org/wgbh/nova/physics/absolute-hot.html (hint: there is no answer).

Re: APOD: Sunspot Loops in Ultraviolet (2011 Apr 10)

Posted: Mon Apr 11, 2011 7:48 pm
by neufer
nz1m wrote:
nz1m wrote:
Question: As the speed of light is "absolute." And "absolute zero" is, well, absolute. Is there an "absolute" high temperature?
OK... here's the real answer: http://www.pbs.org/wgbh/nova/physics/absolute-hot.html (hint: there is no answer).
Absolute temperature (Physics), the temperature as measured on a scale determined
by certain general thermo-dynamic principles, and reckoned from the absolute zero.

Absolute, a. [L. absolutus, p. p. of absolVERE to set free, to absolve; ab + solVERE to loose.]

1. Loosed from any limitation or condition; uncontrolled; unrestricted; unconditional; as, absolute authority, monarchy, sovereignty, an absolute promise or command; absolute power; an absolute monarch.

2. Complete in itself; perfect; consummate; faultless; as, absolute perfection; absolute beauty.

3. Viewed apart from modifying influences or without comparison with other objects; actual; real; -- opposed to relative and comparative; as, absolute motion; absolute time or space. Absolute rights and duties are such as pertain to man in a state of nature as contradistinguished from relative rights and duties, or such as pertain to him in his social relations.

4. Loosed from, or unconnected by, dependence on any other being; self-existent; self-sufficing. &hand; In this sense God is called the Absolute by the Theist. The term is also applied by the Pantheist to the universe, or the total of all existence, as only capable of relations in its parts to each other and to the whole, and as dependent for its existence and its phenomena on its mutually depending forces and their laws.

5. Capable of being thought or conceived by itself alone; unconditioned; non-relative. &hand; It is in dispute among philosopher whether the term, in this sense, is not applied to a mere logical fiction or abstraction, or whether the absolute, as thus defined, can be known, as a reality, by the human intellect.
Image
6. Positive; clear; certain; not doubtful.

7. Authoritative; peremptory.

8. (Chem.) Pure; unmixed; as, absolute alcohol.

9. (Gram.) Not immediately dependent on the other parts of the sentence in government; as, the case absolute. See Ablative absolute, under Ablative.
....................................................................................
Absolute curvature (Geom.), that curvature of a curve of double curvature, which is measured in the osculating plane of the curve.

Absolute equation (Astron.), the sum of the optic and eccentric equations.

http://www.absoluteastronomy.com/

Absolute space (Physics), space considered without relation to material limits or objects.

Absolute terms. (Alg.), such as are known, or which do not contain the unknown quantity.

Absolute zero (Physics), the beginning, or zero point, in the scale of absolute temperature. It is equivalent to -273° centigrade or -459.4° Fahrenheit.
Art Image Neuendorffer