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	<title>The Helioviewer Project Blog &#187; SDO</title>
	<atom:link href="http://blog.helioviewer.org/category/sdo/feed/" rel="self" type="application/rss+xml" />
	<link>http://blog.helioviewer.org</link>
	<description>Explore your heliosphere</description>
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		<title>JHelioviewer 2.2.1 Released</title>
		<link>http://blog.helioviewer.org/2012/04/10/jhelioviewer-2-2-1-released/</link>
		<comments>http://blog.helioviewer.org/2012/04/10/jhelioviewer-2-2-1-released/#comments</comments>
		<pubDate>Tue, 10 Apr 2012 09:39:36 +0000</pubDate>
		<dc:creator>Daniel Müller</dc:creator>
				<category><![CDATA[AIA]]></category>
		<category><![CDATA[Development]]></category>
		<category><![CDATA[General]]></category>
		<category><![CDATA[HMI]]></category>
		<category><![CDATA[JHelioviewer]]></category>
		<category><![CDATA[LASCO]]></category>
		<category><![CDATA[Movies]]></category>
		<category><![CDATA[Releases]]></category>
		<category><![CDATA[Science]]></category>
		<category><![CDATA[SDO]]></category>
		<category><![CDATA[SOHO]]></category>

		<guid isPermaLink="false">http://blog.helioviewer.org/?p=809</guid>
		<description><![CDATA[A new version of JHelioviewer is available for download. What&#8217;s new? This update release contains improved movie export functionality, an updated LASCO C2 coronagraph mask, the new SDO Cutout Service plug-in plus various bug fixes. The new movie export menu makes it easier to set the exact scaling of the area you are interested in, [...]]]></description>
			<content:encoded><![CDATA[<p> <a href="http://jhelioviewer.org">A  new version of JHelioviewer is available for download.</a> What&#8217;s new? This update release contains improved movie export functionality, an updated LASCO C2 coronagraph mask, the new SDO Cutout Service plug-in plus various bug fixes.</p>
<p>The new movie export menu makes it easier to set the exact scaling of the area you are interested in, and the processing itself is now performed on the graphics card using OpenGL:</p>
<p><img src="http://blog.helioviewer.org/wp-content/uploads/2012/04/JHV_2.2.1_Movie_Export.png" alt="New movie export menu" /></p>
<p>The SDO Cutout Service plug-in allows you to request science-quality image data from the SDO/AIA and HMI instruments for the region of interest and time range selected in JHelioviewer:</p>
<p><img src="http://blog.helioviewer.org/wp-content/uploads/2012/04/JHV_SDO_Cutout_Plugin.png" width="546 px" alt="SDO Cutout Service plug-in" /></p>
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		<slash:comments>0</slash:comments>
		</item>
		<item>
		<title>SDO data lag</title>
		<link>http://blog.helioviewer.org/2012/04/02/sdo-data-lag/</link>
		<comments>http://blog.helioviewer.org/2012/04/02/sdo-data-lag/#comments</comments>
		<pubDate>Mon, 02 Apr 2012 13:54:54 +0000</pubDate>
		<dc:creator>jack</dc:creator>
				<category><![CDATA[AIA]]></category>
		<category><![CDATA[General]]></category>
		<category><![CDATA[HMI]]></category>
		<category><![CDATA[SDO]]></category>

		<guid isPermaLink="false">http://blog.helioviewer.org/?p=789</guid>
		<description><![CDATA[As you may have noticed, we are currently experiencing a lag in the availability of SDO images. The lag is happening upstream of Helioviewer. The Helioviewer Project provides images of scientific data. The science data is beamed down from the spacecraft , to a dedicated ground station (as outlined here) in New Mexico. The packets [...]]]></description>
			<content:encoded><![CDATA[<p>As you may have noticed, we are currently experiencing a lag in the availability of SDO images.  The lag is happening upstream of Helioviewer.  The Helioviewer Project provides images of scientific data.  The science data is beamed down from the spacecraft , to a dedicated ground station (as <a href="http://blog.helioviewer.org/2012/03/29/where-is-the-solar-dynamics-observatory-right-now/">outlined here</a>) in New Mexico.  The packets of data are first re-assembled to form the raw science data, and then have some corrections applied to yield data suitable for science applications.  Data is constantly streaming off the spacecraft and being processed through this pipeline, which involves many different locations and institutions.</p>
<p>One of those science applications is visualization of the data.  The Helioviewer Project takes that science data and converts those data to JPEG2000 images, which we then make available via <a href="http://www.helioviewer.org">www.helioviewer.org</a> and <a href="http://www.jhelioviewer.org">www.jhelioviewer.org</a>.  We have to have the science data available to make the JPEG2000 images.</p>
<p>As soon as new SDO-AIA and HMI images become available, we will make them available to you.  We regret the interruption to the stream of SDO data.  Other data-sets are unaffected, and are available as usual.</p>
]]></content:encoded>
			<wfw:commentRss>http://blog.helioviewer.org/2012/04/02/sdo-data-lag/feed/</wfw:commentRss>
		<slash:comments>4</slash:comments>
		</item>
		<item>
		<title>Where is the Solar Dynamics Observatory right now?</title>
		<link>http://blog.helioviewer.org/2012/03/29/where-is-the-solar-dynamics-observatory-right-now/</link>
		<comments>http://blog.helioviewer.org/2012/03/29/where-is-the-solar-dynamics-observatory-right-now/#comments</comments>
		<pubDate>Thu, 29 Mar 2012 16:35:48 +0000</pubDate>
		<dc:creator>jack</dc:creator>
				<category><![CDATA[Science]]></category>
		<category><![CDATA[SDO]]></category>

		<guid isPermaLink="false">http://blog.helioviewer.org/?p=699</guid>
		<description><![CDATA[It&#8217;s here. Why does the orbit have this shape? It&#8217;s because SDO takes so many large images that it has to have its own ground station to receive all that data (around 1.5 TB/day). In order to keep the flow of data running off the spacecraft, its geosynchronous orbit was designed to maintain contact with [...]]]></description>
			<content:encoded><![CDATA[<p>It&#8217;s <a href="http://www.n2yo.com/?s=36395">here</a>.</p>
<p>Why does the orbit have this shape?  It&#8217;s because <a href="http://www.nasa.gov/externalflash/LWS/">SDO</a> takes so many large images that it has to have its own <a href="http://en.wikipedia.org/wiki/Ground_station">ground station</a> to receive all that data (around 1.5 TB/day).  In order to keep the flow of data running off the spacecraft, its <a href="http://en.wikipedia.org/wiki/Geosynchronous_orbit">geosynchronous orbit</a> was designed to maintain contact with the <a href="http://en.wikipedia.org/wiki/Solar_Dynamics_Observatory#Communications">ground station</a>.  For more detail, please go to <a href="http://sdo.gsfc.nasa.gov/mission/project/specs.php">http://sdo.gsfc.nasa.gov/mission/project/specs.php</a>.</p>
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		<slash:comments>1</slash:comments>
		</item>
		<item>
		<title>User highlight: back-sided eruption appears to cause a front-sided eruption</title>
		<link>http://blog.helioviewer.org/2012/03/27/user-highlight-back-sided-eruption-causes-a-front-sided-eruption/</link>
		<comments>http://blog.helioviewer.org/2012/03/27/user-highlight-back-sided-eruption-causes-a-front-sided-eruption/#comments</comments>
		<pubDate>Tue, 27 Mar 2012 13:28:04 +0000</pubDate>
		<dc:creator>jack</dc:creator>
				<category><![CDATA[AIA]]></category>
		<category><![CDATA[Helioviewer.org]]></category>
		<category><![CDATA[Science]]></category>
		<category><![CDATA[User Highlights]]></category>

		<guid isPermaLink="false">http://blog.helioviewer.org/?p=770</guid>
		<description><![CDATA[Helioviewer.org and YouTube user danielchangck found this event: What happened? Well, there was an eruption on the back side of the Sun, that caused a propagating disturbance in the solar atmosphere. that appears to have triggered a prominence lift-off on the front-side of the Sun. This is a great example of how the high cadence, [...]]]></description>
			<content:encoded><![CDATA[<p><a href="http://www.helioviewer.org">Helioviewer.org</a> and <a href="http://www.youtube.com">YouTube</a> user <a href="http://www.youtube.com/user/danielchangck">danielchangck</a> found this event:</p>
<p><span style="text-align:center; display: block;"><a href="http://blog.helioviewer.org/2012/03/27/user-highlight-back-sided-eruption-causes-a-front-sided-eruption/"><img src="http://img.youtube.com/vi/izYPLAn0W4g/2.jpg" alt="" /></a></span></p>
<p>What happened?  Well, there was an eruption on the back side of the Sun, that caused a propagating disturbance in the solar atmosphere.  that appears to have triggered a prominence lift-off on the front-side of the Sun.  This is a great example of how the high cadence, continuous observations from  <a href="http://sdo.gsfc.nasa.gov">Solar Dynamics Observatory</a>  give us a much better view of how distant parts of the Sun can physically influence each other.  We liked this event so much we made and uploaded some movies of our own.  The lower cadence of these movies allows you to see the swaying of coronal material in response to the disturbance from the initial eruption.</p>
<p><span style="text-align:center; display: block;"><a href="http://blog.helioviewer.org/2012/03/27/user-highlight-back-sided-eruption-causes-a-front-sided-eruption/"><img src="http://img.youtube.com/vi/3FeQ611CE0Q/2.jpg" alt="" /></a></span></p>
<p><span style="text-align:center; display: block;"><a href="http://blog.helioviewer.org/2012/03/27/user-highlight-back-sided-eruption-causes-a-front-sided-eruption/"><img src="http://img.youtube.com/vi/u1yFBOdO82g/2.jpg" alt="" /></a></span></p>
<p><span style="text-align:center; display: block;"><a href="http://blog.helioviewer.org/2012/03/27/user-highlight-back-sided-eruption-causes-a-front-sided-eruption/"><img src="http://img.youtube.com/vi/xGeOpn-819I/2.jpg" alt="" /></a></span></p>
<p>Thanks to <a href="http://www.youtube.com/user/danielchangck">danielchangck</a> for sharing <a href="http://www.youtube.com/watch?v=izYPLAn0W4g">this movie</a> with other users of <a href="http://www.helioviewer.org">Helioviewer.org</a>.</p>
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		<slash:comments>2</slash:comments>
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		<item>
		<title>Spiralling eruption close to the south pole</title>
		<link>http://blog.helioviewer.org/2012/03/23/spiraling-eruption-close-to-the-south-pole/</link>
		<comments>http://blog.helioviewer.org/2012/03/23/spiraling-eruption-close-to-the-south-pole/#comments</comments>
		<pubDate>Fri, 23 Mar 2012 16:37:19 +0000</pubDate>
		<dc:creator>jack</dc:creator>
				<category><![CDATA[AIA]]></category>
		<category><![CDATA[General]]></category>
		<category><![CDATA[Science]]></category>
		<category><![CDATA[SDO]]></category>
		<category><![CDATA[User Highlights]]></category>

		<guid isPermaLink="false">http://blog.helioviewer.org/?p=757</guid>
		<description><![CDATA[A colleague who works with LASCO data yesterday found this lovely spiralling eruption close to the south pole. It&#8217;s a great example of how the magnetic field can influence the dynamics of erupting plasma. The eruption starts around 00:13 in the above video.]]></description>
			<content:encoded><![CDATA[<p>A colleague who works with LASCO data yesterday found this lovely spiralling eruption close to the south pole.</p>
<p><span style="text-align:center; display: block;"><a href="http://blog.helioviewer.org/2012/03/23/spiraling-eruption-close-to-the-south-pole/"><img src="http://img.youtube.com/vi/D3Qw-r2rAFQ/2.jpg" alt="" /></a></span></p>
<p>It&#8217;s a great example of how the magnetic field can influence the dynamics of erupting plasma.  The eruption starts around 00:13 in the above video.</p>
]]></content:encoded>
			<wfw:commentRss>http://blog.helioviewer.org/2012/03/23/spiraling-eruption-close-to-the-south-pole/feed/</wfw:commentRss>
		<slash:comments>0</slash:comments>
		</item>
		<item>
		<title>Spotted: another coronal cavity</title>
		<link>http://blog.helioviewer.org/2012/03/16/spotted-another-coronal-cavity/</link>
		<comments>http://blog.helioviewer.org/2012/03/16/spotted-another-coronal-cavity/#comments</comments>
		<pubDate>Fri, 16 Mar 2012 15:21:51 +0000</pubDate>
		<dc:creator>jack</dc:creator>
				<category><![CDATA[AIA]]></category>
		<category><![CDATA[Helioviewer.org]]></category>
		<category><![CDATA[Science]]></category>
		<category><![CDATA[User Highlights]]></category>

		<guid isPermaLink="false">http://blog.helioviewer.org/?p=744</guid>
		<description><![CDATA[YouTube and Helioviewer.org user sedge2002 found another coronal cavity. This one was on the Sun late 2011 to early 2012. It appears towards the end of this movie, at around 30-45 degrees clockwise from the north pole of Sun, above the limb: Thanks to sedge2002 for making this movie and sharing it with other users [...]]]></description>
			<content:encoded><![CDATA[<p><a href="http://www.youtube.com">YouTube</a> and <a href="http://www.helioviewer.org">Helioviewer.org</a> user <a href="http://www.youtube.com/user/sedge2002">sedge2002</a> found another coronal cavity.  This one was on the Sun late 2011 to early 2012.  It appears towards the end of this movie, at around 30-45 degrees clockwise from the north pole of Sun, above the limb:</p>
<p><span style="text-align:center; display: block;"><a href="http://blog.helioviewer.org/2012/03/16/spotted-another-coronal-cavity/"><img src="http://img.youtube.com/vi/EdiCRzTS5iw/2.jpg" alt="" /></a></span></p>
<p>Thanks to <a href="http://www.youtube.com/user/sedge2002">sedge2002</a> for making this movie and sharing it with other users of <a href="http://www.helioviewer.org">Helioviewer.org</a>.  As the movie demonstrates, coronal cavities do occur, and so <a href="http://www.youtube.com/watch?v=8eWh8mIX-DI">the one you may have earlier in the week</a>, whilst a great example of a coronal cavity, is definitely not unique.  What is a coronal cavity?  Let <a href="http://www.thesuntoday.org/current-observations/unidentified-sun-object-is-identified-a-little-black-spot-on-the-sun-today/">Dr. Alex Young of the The Sun Today tell you</a>:</p>
<p><span style="text-align:center; display: block;"><a href="http://blog.helioviewer.org/2012/03/16/spotted-another-coronal-cavity/"><img src="http://img.youtube.com/vi/82l46fpd-ic/2.jpg" alt="" /></a></span></p>
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		<slash:comments>6</slash:comments>
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		<title>Eruption seen coming from the back of the Sun</title>
		<link>http://blog.helioviewer.org/2012/02/02/eruption-seen-coming-from-the-back-of-the-sun/</link>
		<comments>http://blog.helioviewer.org/2012/02/02/eruption-seen-coming-from-the-back-of-the-sun/#comments</comments>
		<pubDate>Thu, 02 Feb 2012 16:47:44 +0000</pubDate>
		<dc:creator>jack</dc:creator>
				<category><![CDATA[AIA]]></category>
		<category><![CDATA[Movies]]></category>
		<category><![CDATA[Science]]></category>
		<category><![CDATA[STEREO]]></category>
		<category><![CDATA[User Highlights]]></category>

		<guid isPermaLink="false">http://blog.helioviewer.org/?p=715</guid>
		<description><![CDATA[YouTube and Helioviewer user goggog67 spotted this event that clearly happened on the other side of the Sun. The material travels in to the field of view from its launch location, which can be seen in STEREO-B EUVI images. If you go to STEREO latest image selector and select &#8216;Behind EUVI 195&#8242;, pick a resolution [...]]]></description>
			<content:encoded><![CDATA[<p><a href="http://www.youtube.com">YouTube</a> and <a href="http://www.helioviewer.org">Helioviewer</a> user <a href="http://www.youtube.com/user/goggog67">goggog67</a> spotted this event that clearly happened on the <em>other side of the Sun</em>.</p>
<p><span style="text-align:center; display: block;"><a href="http://blog.helioviewer.org/2012/02/02/eruption-seen-coming-from-the-back-of-the-sun/"><img src="http://img.youtube.com/vi/-l0wnvOxAs4/2.jpg" alt="" /></a></span></p>
<p>The material travels in to the field of view from its launch location, which can be seen in STEREO-B EUVI images. If you go to <a href="http://stereo.gsfc.nasa.gov/cgi-bin/images">STEREO latest image selector</a> and select &#8216;Behind EUVI 195&#8242;, pick a resolution of 512 x 512, type in a start and end date of 20120202, and select &#8216;Slideshow&#8217;, you get an animation of the event as seen from STEREO-B.  There is a filament eruption on the upper left of the disk (it is hard to spot) which is the same material seen in the AIA 304 movie above:<br />
<a href="http://blog.helioviewer.org/wp-content/uploads/2012/02/20120202_140530_n7euB_195.jpg"><img src="http://blog.helioviewer.org/wp-content/uploads/2012/02/20120202_140530_n7euB_195.jpg" alt="" title="20120202_140530_n7euB_195" width="512" height="512" class="aligncenter size-full wp-image-718" /></a></p>
<p>and a flare in more or less the same area of the Sun &#8211; look for the very bright patch at the limb of the Sun at the upper left of the disk.<br />
<a href="http://blog.helioviewer.org/wp-content/uploads/2012/02/20120202_141530_n7euB_195.jpg"><img src="http://blog.helioviewer.org/wp-content/uploads/2012/02/20120202_141530_n7euB_195.jpg" alt="" title="20120202_141530_n7euB_195" width="512" height="512" class="aligncenter size-full wp-image-719" /></a></p>
<p>Thanks to <a href="http://www.youtube.com/user/goggog67">goggog67</a> for spotting this event and sharing it with us!</p>
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			<wfw:commentRss>http://blog.helioviewer.org/2012/02/02/eruption-seen-coming-from-the-back-of-the-sun/feed/</wfw:commentRss>
		<slash:comments>2</slash:comments>
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		<title>User highlight: flares and loops</title>
		<link>http://blog.helioviewer.org/2012/01/16/user-highlight-flares-and-loops/</link>
		<comments>http://blog.helioviewer.org/2012/01/16/user-highlight-flares-and-loops/#comments</comments>
		<pubDate>Mon, 16 Jan 2012 12:55:52 +0000</pubDate>
		<dc:creator>jack</dc:creator>
				<category><![CDATA[AIA]]></category>
		<category><![CDATA[Movies]]></category>
		<category><![CDATA[User Highlights]]></category>

		<guid isPermaLink="false">http://blog.helioviewer.org/?p=672</guid>
		<description><![CDATA[YouTube and users losyziemi, MeireRuiz7 and goggog67 have created a wonderful series of movies that show a flaring system of loops coming from a source active region just coming round the limb of the Sun. Thanks for sharing these great movies! Solar flares are caused by the interaction of particles accelerated by magnetic reconnection with [...]]]></description>
			<content:encoded><![CDATA[<p><a href="http://www.youtube.com">YouTube</a> and <a href="http://www.helioviewer.org"></a> users <a href="http://www.youtube.com/user/losyziemi">losyziemi</a>, <a href="http://www.youtube.com/user/MeireRuiz7">MeireRuiz7</a> and <a href="http://www.youtube.com/user/goggog67">goggog67</a> have created a wonderful series of movies that show a flaring system of loops coming from a source active region just coming round the limb of the Sun.   Thanks for sharing these great movies!</p>
<p><a href="http://en.wikipedia.org/wiki/Solar_flares">Solar flares</a> are caused by the interaction of particles accelerated by <a href="http://en.wikipedia.org/wiki/Magnetic_reconnection">magnetic reconnection </a> with the surrounding plasma.  In the movies below, you can see bright loop-top sources filling in their supporting loops.  This caused by the flare-accelerated particles striking the surrounding plasma, and heating it up; as that plasma cools down, it appears in the AIA wavebands.  This event should be visible in all the other AIA wavebands (which correspond approximately to different temperatures in the solar plasma).</p>
<p><span style="text-align:center; display: block;"><a href="http://blog.helioviewer.org/2012/01/16/user-highlight-flares-and-loops/"><img src="http://img.youtube.com/vi/42xK3x3vCR8/2.jpg" alt="" /></a></span></p>
<p><span style="text-align:center; display: block;"><a href="http://blog.helioviewer.org/2012/01/16/user-highlight-flares-and-loops/"><img src="http://img.youtube.com/vi/bAA-Tw5bRys/2.jpg" alt="" /></a></span></p>
<p><span style="text-align:center; display: block;"><a href="http://blog.helioviewer.org/2012/01/16/user-highlight-flares-and-loops/"><img src="http://img.youtube.com/vi/7dXWn19mk_0/2.jpg" alt="" /></a></span></p>
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		<slash:comments>0</slash:comments>
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		<title>Interruption in LASCO, EIT, COR1/2, EUVI image availability</title>
		<link>http://blog.helioviewer.org/2012/01/15/interruption-in-lasco-eit-cor12-euvi-image-availability/</link>
		<comments>http://blog.helioviewer.org/2012/01/15/interruption-in-lasco-eit-cor12-euvi-image-availability/#comments</comments>
		<pubDate>Sun, 15 Jan 2012 15:13:26 +0000</pubDate>
		<dc:creator>jack</dc:creator>
				<category><![CDATA[AIA]]></category>
		<category><![CDATA[COR2]]></category>
		<category><![CDATA[EIT]]></category>
		<category><![CDATA[General]]></category>
		<category><![CDATA[HMI]]></category>
		<category><![CDATA[LASCO]]></category>
		<category><![CDATA[MDI]]></category>

		<guid isPermaLink="false">http://blog.helioviewer.org/?p=670</guid>
		<description><![CDATA[The most recent LASCO, EIT, COR1/2 and EUVI images are currently unavailable to Helioviewer Project browse clients. This is because the computer that converts the science data to JPEG 2000 images experienced a mechanical failure on Friday January 13th. We will replace the failed machine, and make an announcement via the blog concerning the resumption [...]]]></description>
			<content:encoded><![CDATA[<p>The most recent LASCO, EIT, COR1/2 and EUVI images are currently unavailable to Helioviewer Project browse clients.  This is because the computer that converts the science data to JPEG 2000 images experienced a mechanical failure on Friday January 13th.  We will replace the failed machine, and make an announcement via the blog concerning the resumption of the availability of images from LASCO, EIT, COR1/2 and EUVI.  We are apologize for any inconvenience this may cause.  Finally, images from AIA and HMI should be unaffected.</p>
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		<title>Comet Lovejoy &#8211; special observations coming up.</title>
		<link>http://blog.helioviewer.org/2011/12/15/comet-lovejoy-special-observations-coming-up/</link>
		<comments>http://blog.helioviewer.org/2011/12/15/comet-lovejoy-special-observations-coming-up/#comments</comments>
		<pubDate>Thu, 15 Dec 2011 02:47:06 +0000</pubDate>
		<dc:creator>jack</dc:creator>
				<category><![CDATA[AIA]]></category>
		<category><![CDATA[Comets]]></category>
		<category><![CDATA[General]]></category>
		<category><![CDATA[LASCO]]></category>
		<category><![CDATA[SDO]]></category>
		<category><![CDATA[User Highlights]]></category>

		<guid isPermaLink="false">http://blog.helioviewer.org/?p=624</guid>
		<description><![CDATA[Comet Lovejoy will be passing close to the Sun in the next couple of days. SDO will be taking special observations of the comet beginning 22:59 UT on 2011/12/15 (5.59pm 2011/12/15, Eastern Time), and lasting for a couple of hours. The comet will pass behind the solar limb at around 00:07 UT 2011/12/16 (7:07pm 2011/12/15, [...]]]></description>
			<content:encoded><![CDATA[<p><a href="http://www.space.com/13925-sungrazing-comet-lovejoy-sun-death-dive.html">Comet Lovejoy</a> will be passing close to the Sun in the next couple of days.  SDO will be taking special observations of the comet beginning 22:59 UT on 2011/12/15 (5.59pm 2011/12/15, Eastern Time), and lasting for a couple of hours.  The comet will pass behind the solar limb at around 00:07 UT 2011/12/16 (7:07pm 2011/12/15, Eastern Time).  There is a chance the comet will survive its encounter with the Sun.</p>
<p>SDO/AIA will take special observations to view the comet; AIA will change its pointing and point slightly away from the center of the Sun in order to try to get more observations of the comet as it gets close to the disk of the Sun.</p>
<p>Why are these observations being taken?  Well, we are looking for something like we saw on 2011/07/05 this year.  On that day a comet fell in to the Sun.  These kinds of comets have been seen before in LASCO-C3 and LASCO-C2 images.  What was new about this observation was that <em>for the first time the comet was seen against the disk of the Sun</em>.  The video below gives a description of what was seen.</p>
<p><span style="text-align:center; display: block;"><a href="http://blog.helioviewer.org/2011/12/15/comet-lovejoy-special-observations-coming-up/"><img src="http://img.youtube.com/vi/6Yzg4QoP64A/2.jpg" alt="" /></a></span></p>
<p>SDO/AIA detects different wavelengths of light.  So in order for us to see it, the comet must have been emitting at those different wavelengths, and the comet must have disintegrated in to a big enough cloud of ionized gas for us to see it.  So the big scientific question about seeing this comet against the disk of the Sun is explaining both how it came to be emitting at wavelengths that SDO/AIA could see, and figuring out how it could have disintegrated.  This is an active area of research, with presentations on this subject given last week at the <a href="http://www.agu.org">American Geophysical Union</a>&#8216;s <a href="http://sites.agu.org/fallmeeting/">Fall Meeting</a>, and a paper set to appear in Science.</p>
<p>Comet Lovejoy is already visible.  <a href="http://www.youtube.com">YouTube</a> and <a href="http://www.helioviewer.org"></a> user <a href="http://www.youtube.com/user/otraLoly?feature=watch">otraLoly</a> posted a <a href="http://www.youtube.com/watch?v=JLwwhus3cJU">video earlier on today</a> of Comet Lovejoy entering the field of view of <a href="http://lasco-www.nrl.navy.mil/index.php?p=content/about_lasco">LASCO C3</a>.</p>
<p><span style="text-align:center; display: block;"><a href="http://blog.helioviewer.org/2011/12/15/comet-lovejoy-special-observations-coming-up/"><img src="http://img.youtube.com/vi/JLwwhus3cJU/2.jpg" alt="" /></a></span></p>
<p>We hope you enjoy tracking Comet Lovejoy as it gets closer to the Sun.  Please let us know if you have any further questions about the Helioviewer Project and Comet Lovejoy.</p>
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