Astronomy Picture of the Day

Posted By admin On April 10, 2011 @ 6:16 am In Photo Essays | Comments Disabled

 

The above image shows, however, that even during off days the Sun’s surface is a busy place.

 

^[1]

Sunspot Loops in Ultraviolet
Credit: TRACE Project ^[2], NASA ^[3]

Explanation: It was a quiet day on the Sun ^[4]. The above image shows, however, that even during off days the Sun’s surface ^[5] is a busy place. Shown in ultraviolet light ^[6], the relatively cool dark regions have temperatures of thousands of degrees Celsius ^[7]. Large sunspot group ^[8] AR 9169 from the last solar cycle ^[9] is visible as the bright area near the horizon. The bright glowing gas ^[10] flowing around the sunspots ^[11] has a temperature of over one million degrees Celsius ^[12]. The reason for the high temperatures is unknown ^[13] but thought to be related to the rapidly changing magnetic field ^[14] loops that channel solar plasma. Large sunspot group AR 9169 ^[15] moved across the Sun ^[16] during 2000 September and decayed in a few weeks.

Visit the NASA/JPL website to view more Astronomy Pictures of the Day ^[17]

Article printed from Recorder Online: http://www.berthoudrecorder.com

URL to article: http://www.berthoudrecorder.com/2011/04/10/astronomy-picture-of-the-day-54/

URLs in this post:

[1] Image: http://www.berthoudrecorder.com/wp-content/uploads/2011/04/sunspotloops_trace_898.jpg

[2] TRACE Project: http://trace.lmsal.com/

[3] NASA: http://www.nasa.gov/

[4] Sun: http://en.wikipedia.org/wiki/Sun

[5] Sun’s surface: http://apod.nasa.gov/apod/ap001115.html

[6] ultraviolet light: http://science.hq.nasa.gov/kids/imagers/ems/uv.html

[7] Celsius: http://www.astro.uu.se/history/Celsius_eng.html

[8] Large sunspot group: http://apod.nasa.gov/apod/ap031027.html

[9] solar cycle: http://apod.nasa.gov/apod/ap071203.html

[10] bright glowing gas: http://apod.nasa.gov/apod/ap000608.html

[11] sunspots: http://apod.nasa.gov/apod/ap981005.html

[12] Celsius: http://www.wbuf.noaa.gov/tempfc.htm

[13] unknown: http://apod.nasa.gov/apod/ap000928.html

[14] magnetic field: http://solar.physics.montana.edu/YPOP/Spotlight/Magnetic/

[15] sunspot group AR 9169: http://apod.nasa.gov/apod/ap000925.html

[16] Sun: http://apod.nasa.gov/apod/sun.html

[17] Astronomy Pictures of the Day: http://antwrp.gsfc.nasa.gov/apod/

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