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	<title>Comments on: Martian dunes under the microscope</title>
	<atom:link href="http://blogs.discovermagazine.com/badastronomy/2010/12/07/martian-dunes-under-the-microscope/feed/" rel="self" type="application/rss+xml" />
	<link>http://blogs.discovermagazine.com/badastronomy/2010/12/07/martian-dunes-under-the-microscope/</link>
	<description>I am an astronomer, writer, and skeptic. I likes reality the way it is, and I aims to keep it that way. My real name is Phil Plait, and I run the Bad Astronomy blog.</description>
	<lastBuildDate>Fri, 25 May 2012 00:20:50 +0000</lastBuildDate>
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		<title>By: Bademart</title>
		<link>http://blogs.discovermagazine.com/badastronomy/2010/12/07/martian-dunes-under-the-microscope/comment-page-1/#comment-467656</link>
		<dc:creator>Bademart</dc:creator>
		<pubDate>Sun, 15 Jan 2012 19:39:20 +0000</pubDate>
		<guid isPermaLink="false">http://blogs.discovermagazine.com/badastronomy/?p=24568#comment-467656</guid>
		<description>Well, if life is chemistry... Is not all chemistry life of some sort?</description>
		<content:encoded><![CDATA[<p>Well, if life is chemistry&#8230; Is not all chemistry life of some sort?</p>
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		<title>By: Gary Ansorge</title>
		<link>http://blogs.discovermagazine.com/badastronomy/2010/12/07/martian-dunes-under-the-microscope/comment-page-1/#comment-343364</link>
		<dc:creator>Gary Ansorge</dc:creator>
		<pubDate>Thu, 09 Dec 2010 14:20:58 +0000</pubDate>
		<guid isPermaLink="false">http://blogs.discovermagazine.com/badastronomy/?p=24568#comment-343364</guid>
		<description>33.   Messier Tidy Upper

Touche!!!

Gary 7</description>
		<content:encoded><![CDATA[<p>33.   Messier Tidy Upper</p>
<p>Touche!!!</p>
<p>Gary 7</p>
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	<item>
		<title>By: Messier Tidy Upper</title>
		<link>http://blogs.discovermagazine.com/badastronomy/2010/12/07/martian-dunes-under-the-microscope/comment-page-1/#comment-343321</link>
		<dc:creator>Messier Tidy Upper</dc:creator>
		<pubDate>Thu, 09 Dec 2010 10:33:26 +0000</pubDate>
		<guid isPermaLink="false">http://blogs.discovermagazine.com/badastronomy/?p=24568#comment-343321</guid>
		<description>...Or who can ride a sandworm Fremen style! ;-)</description>
		<content:encoded><![CDATA[<p>&#8230;Or who can ride a sandworm Fremen style! <img src='http://blogs.discovermagazine.com/badastronomy/wp-includes/images/smilies/icon_wink.gif' alt=';-)' class='wp-smiley' /> </p>
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	</item>
	<item>
		<title>By: Gary Ansorge</title>
		<link>http://blogs.discovermagazine.com/badastronomy/2010/12/07/martian-dunes-under-the-microscope/comment-page-1/#comment-343269</link>
		<dc:creator>Gary Ansorge</dc:creator>
		<pubDate>Thu, 09 Dec 2010 04:28:25 +0000</pubDate>
		<guid isPermaLink="false">http://blogs.discovermagazine.com/badastronomy/?p=24568#comment-343269</guid>
		<description>31.   Brian Too

&quot;Only a fool or a madman does that.&quot;

,,,or somebody who can run really, REALLY fast,,,

Gary 7</description>
		<content:encoded><![CDATA[<p>31.   Brian Too</p>
<p>&#8220;Only a fool or a madman does that.&#8221;</p>
<p>,,,or somebody who can run really, REALLY fast,,,</p>
<p>Gary 7</p>
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	<item>
		<title>By: Brian Too</title>
		<link>http://blogs.discovermagazine.com/badastronomy/2010/12/07/martian-dunes-under-the-microscope/comment-page-1/#comment-343237</link>
		<dc:creator>Brian Too</dc:creator>
		<pubDate>Thu, 09 Dec 2010 01:05:16 +0000</pubDate>
		<guid isPermaLink="false">http://blogs.discovermagazine.com/badastronomy/?p=24568#comment-343237</guid>
		<description>You can walk there, but step in a broken pattern.  Steady walking attracts the Shai-Hulud.  Only a fool or a madman does that.</description>
		<content:encoded><![CDATA[<p>You can walk there, but step in a broken pattern.  Steady walking attracts the Shai-Hulud.  Only a fool or a madman does that.</p>
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		<title>By: Gary Ansorge</title>
		<link>http://blogs.discovermagazine.com/badastronomy/2010/12/07/martian-dunes-under-the-microscope/comment-page-1/#comment-343112</link>
		<dc:creator>Gary Ansorge</dc:creator>
		<pubDate>Wed, 08 Dec 2010 17:50:38 +0000</pubDate>
		<guid isPermaLink="false">http://blogs.discovermagazine.com/badastronomy/?p=24568#comment-343112</guid>
		<description>Dunes alive, that&#039;s some cool pic there Phil.

If we define life as a self replicating, self sustaining system, then living dunes might be possible but their energy input would appear to be limited to blowing winds,,,not too efficient in my book,,,

&quot;Living&quot; plasmas would seem a great deal more probable. Though how they would pass on a genetic code, both mutable and stable, beats the heck out of me.

Guess, I&#039;ll just have to wait and see,,,

Gary 7</description>
		<content:encoded><![CDATA[<p>Dunes alive, that&#8217;s some cool pic there Phil.</p>
<p>If we define life as a self replicating, self sustaining system, then living dunes might be possible but their energy input would appear to be limited to blowing winds,,,not too efficient in my book,,,</p>
<p>&#8220;Living&#8221; plasmas would seem a great deal more probable. Though how they would pass on a genetic code, both mutable and stable, beats the heck out of me.</p>
<p>Guess, I&#8217;ll just have to wait and see,,,</p>
<p>Gary 7</p>
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		<title>By: Jeff</title>
		<link>http://blogs.discovermagazine.com/badastronomy/2010/12/07/martian-dunes-under-the-microscope/comment-page-1/#comment-343081</link>
		<dc:creator>Jeff</dc:creator>
		<pubDate>Wed, 08 Dec 2010 16:34:26 +0000</pubDate>
		<guid isPermaLink="false">http://blogs.discovermagazine.com/badastronomy/?p=24568#comment-343081</guid>
		<description>in a broad sense, they are alive.  What is life?  The universe itself is alive, anyone who loves this blog understands this.</description>
		<content:encoded><![CDATA[<p>in a broad sense, they are alive.  What is life?  The universe itself is alive, anyone who loves this blog understands this.</p>
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		<title>By: Messier Tidy Upper</title>
		<link>http://blogs.discovermagazine.com/badastronomy/2010/12/07/martian-dunes-under-the-microscope/comment-page-1/#comment-342875</link>
		<dc:creator>Messier Tidy Upper</dc:creator>
		<pubDate>Wed, 08 Dec 2010 07:15:08 +0000</pubDate>
		<guid isPermaLink="false">http://blogs.discovermagazine.com/badastronomy/?p=24568#comment-342875</guid>
		<description>@25. Atreides :

&lt;blockquote&gt;&lt;i&gt;Duke Leto II would be displeased, and you don’t want that.&lt;/i&gt;&lt;/blockquote&gt;

Do you think the God Emperor of Dune would have enough human humour left in him to let us worm our way of that thumping problem - and using the odd bad puns? ;-) 

Incidentally, the Wikipedia page for Arrakis seems to say &quot;Dune&quot; orbits  Canopus instead which I don&#039;t remember from the novels &amp; is much less plausible than the Mu Drac stars given the more massive white supergiants shorter lifespan and lesser likelihood of having planets. (Massive stars like Canopus are very hard on protoplanetary disks tending to destory them via excessive radiation.) Oh well.</description>
		<content:encoded><![CDATA[<p>@25. Atreides :</p>
<blockquote><p><i>Duke Leto II would be displeased, and you don’t want that.</i></p></blockquote>
<p>Do you think the God Emperor of Dune would have enough human humour left in him to let us worm our way of that thumping problem &#8211; and using the odd bad puns? <img src='http://blogs.discovermagazine.com/badastronomy/wp-includes/images/smilies/icon_wink.gif' alt=';-)' class='wp-smiley' />  </p>
<p>Incidentally, the Wikipedia page for Arrakis seems to say &#8220;Dune&#8221; orbits  Canopus instead which I don&#8217;t remember from the novels &#038; is much less plausible than the Mu Drac stars given the more massive white supergiants shorter lifespan and lesser likelihood of having planets. (Massive stars like Canopus are very hard on protoplanetary disks tending to destory them via excessive radiation.) Oh well.</p>
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		<title>By: Messier Tidy Upper</title>
		<link>http://blogs.discovermagazine.com/badastronomy/2010/12/07/martian-dunes-under-the-microscope/comment-page-1/#comment-342867</link>
		<dc:creator>Messier Tidy Upper</dc:creator>
		<pubDate>Wed, 08 Dec 2010 06:56:12 +0000</pubDate>
		<guid isPermaLink="false">http://blogs.discovermagazine.com/badastronomy/?p=24568#comment-342867</guid>
		<description>See : http://stars.astro.illinois.edu/sow/arrakis.html for more info. on the real star via Kaler&#039;s website

&amp; 

http://stars.astro.illinois.edu/sow/dra-t.html 

for a photographic finder chart 

While this :

http://en.wikipedia.org/wiki/Arrakis 

is the wikipage for the fictional exoplanet. :-)</description>
		<content:encoded><![CDATA[<p>See : <a href="http://stars.astro.illinois.edu/sow/arrakis.html" rel="nofollow">http://stars.astro.illinois.edu/sow/arrakis.html</a> for more info. on the real star via Kaler&#8217;s website</p>
<p>&#038; </p>
<p><a href="http://stars.astro.illinois.edu/sow/dra-t.html" rel="nofollow">http://stars.astro.illinois.edu/sow/dra-t.html</a> </p>
<p>for a photographic finder chart </p>
<p>While this :</p>
<p><a href="http://en.wikipedia.org/wiki/Arrakis" rel="nofollow">http://en.wikipedia.org/wiki/Arrakis</a> </p>
<p>is the wikipage for the fictional exoplanet. <img src='http://blogs.discovermagazine.com/badastronomy/wp-includes/images/smilies/icon_smile.gif' alt=':-)' class='wp-smiley' /> </p>
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		<title>By: Messier Tidy Upper</title>
		<link>http://blogs.discovermagazine.com/badastronomy/2010/12/07/martian-dunes-under-the-microscope/comment-page-1/#comment-342866</link>
		<dc:creator>Messier Tidy Upper</dc:creator>
		<pubDate>Wed, 08 Dec 2010 06:55:16 +0000</pubDate>
		<guid isPermaLink="false">http://blogs.discovermagazine.com/badastronomy/?p=24568#comment-342866</guid>
		<description>Great image and  I certainly wouldn&#039;t have guessed Mars by looking at it. Those have got to be the weirdest sand dunes I&#039;ve ever seen! 8)

@ ^ Atreides :  are you counting your comment in that? ;-)

The dunes of Mars would seem far safer than dunes of &lt;i&gt;Dune&lt;/i&gt; where sandworms and space wars are concerned - and yet Martian conditions are actually far harsher and less hospitable atmosphere &amp; pressure~wise. 

Still this picture certainly spices them up too! ;-) 

I agree with Atreides on the need for a scale bar there too.

***

PS. Did you know Arrakis (the real name of &quot;Dune&quot; in the Frank Herbert&#039;s classic novel series) is a real star system name - for Mu Draconis a faint but interesting binary star - two F7 Procyonese dwarfs - located  near the head of the &quot;dragon&quot; roughly in line with Rastaban (Beta Draconis) and forming a triangle with Kuma (Nu Drac). There is a slight confusion here in that the star Arrakis in the 1988 edition  is also listed by the &#039;Alrakis&#039; variant of its name in a later updated 2007 edition of &lt;i&gt;Collins Guide To Stars &amp; Planets&lt;/i&gt;, Ian Ridpath &amp; Wil Tirion, Collins. (First published 1984.)  </description>
		<content:encoded><![CDATA[<p>Great image and  I certainly wouldn&#8217;t have guessed Mars by looking at it. Those have got to be the weirdest sand dunes I&#8217;ve ever seen! <img src='http://blogs.discovermagazine.com/badastronomy/wp-includes/images/smilies/icon_cool.gif' alt='8)' class='wp-smiley' /> </p>
<p>@ ^ Atreides :  are you counting your comment in that? <img src='http://blogs.discovermagazine.com/badastronomy/wp-includes/images/smilies/icon_wink.gif' alt=';-)' class='wp-smiley' /> </p>
<p>The dunes of Mars would seem far safer than dunes of <i>Dune</i> where sandworms and space wars are concerned &#8211; and yet Martian conditions are actually far harsher and less hospitable atmosphere &#038; pressure~wise. </p>
<p>Still this picture certainly spices them up too! <img src='http://blogs.discovermagazine.com/badastronomy/wp-includes/images/smilies/icon_wink.gif' alt=';-)' class='wp-smiley' />  </p>
<p>I agree with Atreides on the need for a scale bar there too.</p>
<p>***</p>
<p>PS. Did you know Arrakis (the real name of &#8220;Dune&#8221; in the Frank Herbert&#8217;s classic novel series) is a real star system name &#8211; for Mu Draconis a faint but interesting binary star &#8211; two F7 Procyonese dwarfs &#8211; located  near the head of the &#8220;dragon&#8221; roughly in line with Rastaban (Beta Draconis) and forming a triangle with Kuma (Nu Drac). There is a slight confusion here in that the star Arrakis in the 1988 edition  is also listed by the &#8216;Alrakis&#8217; variant of its name in a later updated 2007 edition of <i>Collins Guide To Stars &#038; Planets</i>, Ian Ridpath &#038; Wil Tirion, Collins. (First published 1984.)</p>
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		<title>By: Atreides</title>
		<link>http://blogs.discovermagazine.com/badastronomy/2010/12/07/martian-dunes-under-the-microscope/comment-page-1/#comment-342771</link>
		<dc:creator>Atreides</dc:creator>
		<pubDate>Wed, 08 Dec 2010 01:14:23 +0000</pubDate>
		<guid isPermaLink="false">http://blogs.discovermagazine.com/badastronomy/?p=24568#comment-342771</guid>
		<description>C&#039;mon, only 3 Dune references in 24 comments? Duke Leto II would be displeased, and you don&#039;t want that.

On a serious note, cool picture. What is the scale btw?</description>
		<content:encoded><![CDATA[<p>C&#8217;mon, only 3 Dune references in 24 comments? Duke Leto II would be displeased, and you don&#8217;t want that.</p>
<p>On a serious note, cool picture. What is the scale btw?</p>
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		<title>By: Pete Jackson</title>
		<link>http://blogs.discovermagazine.com/badastronomy/2010/12/07/martian-dunes-under-the-microscope/comment-page-1/#comment-342667</link>
		<dc:creator>Pete Jackson</dc:creator>
		<pubDate>Tue, 07 Dec 2010 21:34:13 +0000</pubDate>
		<guid isPermaLink="false">http://blogs.discovermagazine.com/badastronomy/?p=24568#comment-342667</guid>
		<description>Like many astronomical pictures, this one has the contrast cranked up way too high just to look snappy, so that the sand dunes actually look like completely black depressions (at least in my browser)! Perhaps this is what is confusing No. 12 fernly. By increasing the brightness and reducing the contrast, you can see the dark dunes for what they actually are: beautifully formed ripply  structures lying on top of the rocky plain and, of course, covering up the rocks.</description>
		<content:encoded><![CDATA[<p>Like many astronomical pictures, this one has the contrast cranked up way too high just to look snappy, so that the sand dunes actually look like completely black depressions (at least in my browser)! Perhaps this is what is confusing No. 12 fernly. By increasing the brightness and reducing the contrast, you can see the dark dunes for what they actually are: beautifully formed ripply  structures lying on top of the rocky plain and, of course, covering up the rocks.</p>
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		<title>By: Blakut</title>
		<link>http://blogs.discovermagazine.com/badastronomy/2010/12/07/martian-dunes-under-the-microscope/comment-page-1/#comment-342638</link>
		<dc:creator>Blakut</dc:creator>
		<pubDate>Tue, 07 Dec 2010 20:34:35 +0000</pubDate>
		<guid isPermaLink="false">http://blogs.discovermagazine.com/badastronomy/?p=24568#comment-342638</guid>
		<description>Martian dunes debate wether orbiting lights are artificial or not...</description>
		<content:encoded><![CDATA[<p>Martian dunes debate wether orbiting lights are artificial or not&#8230;</p>
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		<title>By: Mike</title>
		<link>http://blogs.discovermagazine.com/badastronomy/2010/12/07/martian-dunes-under-the-microscope/comment-page-1/#comment-342569</link>
		<dc:creator>Mike</dc:creator>
		<pubDate>Tue, 07 Dec 2010 18:45:42 +0000</pubDate>
		<guid isPermaLink="false">http://blogs.discovermagazine.com/badastronomy/?p=24568#comment-342569</guid>
		<description>&quot;NASA scientist says dune-sized bacteria alive on Mars.&quot;</description>
		<content:encoded><![CDATA[<p>&#8220;NASA scientist says dune-sized bacteria alive on Mars.&#8221;</p>
]]></content:encoded>
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		<title>By: Edward Carney</title>
		<link>http://blogs.discovermagazine.com/badastronomy/2010/12/07/martian-dunes-under-the-microscope/comment-page-1/#comment-342547</link>
		<dc:creator>Edward Carney</dc:creator>
		<pubDate>Tue, 07 Dec 2010 18:00:42 +0000</pubDate>
		<guid isPermaLink="false">http://blogs.discovermagazine.com/badastronomy/?p=24568#comment-342547</guid>
		<description>Has to be one of the most thrilling Mars photos yet.</description>
		<content:encoded><![CDATA[<p>Has to be one of the most thrilling Mars photos yet.</p>
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		<title>By: Michel</title>
		<link>http://blogs.discovermagazine.com/badastronomy/2010/12/07/martian-dunes-under-the-microscope/comment-page-1/#comment-342546</link>
		<dc:creator>Michel</dc:creator>
		<pubDate>Tue, 07 Dec 2010 17:59:46 +0000</pubDate>
		<guid isPermaLink="false">http://blogs.discovermagazine.com/badastronomy/?p=24568#comment-342546</guid>
		<description>&quot;Maybe the dunes share more than just appearances with bacteria…could sand dunes actually be [dun dun dunnnnnn] alive*?

* No. Duh. C’mon.&quot;

Crap can be black. 
Maybe it´s Martian guano. Made from the inside  seeping and oozing outwards. And since Martian gravity is less than ours it can grow and grow and grow.
</description>
		<content:encoded><![CDATA[<p>&#8220;Maybe the dunes share more than just appearances with bacteria…could sand dunes actually be [dun dun dunnnnnn] alive*?</p>
<p>* No. Duh. C’mon.&#8221;</p>
<p>Crap can be black.<br />
Maybe it´s Martian guano. Made from the inside  seeping and oozing outwards. And since Martian gravity is less than ours it can grow and grow and grow.</p>
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	<item>
		<title>By: Michel</title>
		<link>http://blogs.discovermagazine.com/badastronomy/2010/12/07/martian-dunes-under-the-microscope/comment-page-1/#comment-342545</link>
		<dc:creator>Michel</dc:creator>
		<pubDate>Tue, 07 Dec 2010 17:58:12 +0000</pubDate>
		<guid isPermaLink="false">http://blogs.discovermagazine.com/badastronomy/?p=24568#comment-342545</guid>
		<description>Just one question.
What´s the scale?</description>
		<content:encoded><![CDATA[<p>Just one question.<br />
What´s the scale?</p>
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	<item>
		<title>By: Keith Bowden</title>
		<link>http://blogs.discovermagazine.com/badastronomy/2010/12/07/martian-dunes-under-the-microscope/comment-page-1/#comment-342537</link>
		<dc:creator>Keith Bowden</dc:creator>
		<pubDate>Tue, 07 Dec 2010 17:40:07 +0000</pubDate>
		<guid isPermaLink="false">http://blogs.discovermagazine.com/badastronomy/?p=24568#comment-342537</guid>
		<description>&quot;Barsoominate&quot; - good one!</description>
		<content:encoded><![CDATA[<p>&#8220;Barsoominate&#8221; &#8211; good one!</p>
]]></content:encoded>
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	<item>
		<title>By: Geb</title>
		<link>http://blogs.discovermagazine.com/badastronomy/2010/12/07/martian-dunes-under-the-microscope/comment-page-1/#comment-342532</link>
		<dc:creator>Geb</dc:creator>
		<pubDate>Tue, 07 Dec 2010 17:20:18 +0000</pubDate>
		<guid isPermaLink="false">http://blogs.discovermagazine.com/badastronomy/?p=24568#comment-342532</guid>
		<description>@13 Yep, It&#039;ll be &lt;i&gt;Shifting Dunes&lt;/i&gt;:
&quot;They thought they were off for a picnic at the beach, but really they were the beach&#039;s picnic.&quot;
I really need to work on my Taglines...</description>
		<content:encoded><![CDATA[<p>@13 Yep, It&#8217;ll be <i>Shifting Dunes</i>:<br />
&#8220;They thought they were off for a picnic at the beach, but really they were the beach&#8217;s picnic.&#8221;<br />
I really need to work on my Taglines&#8230;</p>
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		<title>By: JP</title>
		<link>http://blogs.discovermagazine.com/badastronomy/2010/12/07/martian-dunes-under-the-microscope/comment-page-1/#comment-342527</link>
		<dc:creator>JP</dc:creator>
		<pubDate>Tue, 07 Dec 2010 17:14:28 +0000</pubDate>
		<guid isPermaLink="false">http://blogs.discovermagazine.com/badastronomy/?p=24568#comment-342527</guid>
		<description>So that face on Mars really wasn&#039;t a monument but an *actual* face?  Heh.

We recently spent an hour-plus at one of the local Science on Tap presentations examining photos of Martian land features.  Good stuff.</description>
		<content:encoded><![CDATA[<p>So that face on Mars really wasn&#8217;t a monument but an *actual* face?  Heh.</p>
<p>We recently spent an hour-plus at one of the local Science on Tap presentations examining photos of Martian land features.  Good stuff.</p>
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		<title>By: Regner Trampedach</title>
		<link>http://blogs.discovermagazine.com/badastronomy/2010/12/07/martian-dunes-under-the-microscope/comment-page-1/#comment-342518</link>
		<dc:creator>Regner Trampedach</dc:creator>
		<pubDate>Tue, 07 Dec 2010 17:01:15 +0000</pubDate>
		<guid isPermaLink="false">http://blogs.discovermagazine.com/badastronomy/?p=24568#comment-342518</guid>
		<description>Thanks for the post, Phil.
But as far as I can see, the dark basaltic sand actually show the shortest wavelength ripples - both on the big black dunes, and in between the crests of the pinkish dunes.
fernly @ 12: When you shake a tub of sand and gravel, the biggest ones will rise to the top, simply because the small grains of sand can sink into the space between the larger gravel. That is the reason farmers each spring find new rocks on their fields. The shaking is performed (mostly) by frost heaving - probably the same on Mars.
    Cheers,  Regner</description>
		<content:encoded><![CDATA[<p>Thanks for the post, Phil.<br />
But as far as I can see, the dark basaltic sand actually show the shortest wavelength ripples &#8211; both on the big black dunes, and in between the crests of the pinkish dunes.<br />
fernly @ 12: When you shake a tub of sand and gravel, the biggest ones will rise to the top, simply because the small grains of sand can sink into the space between the larger gravel. That is the reason farmers each spring find new rocks on their fields. The shaking is performed (mostly) by frost heaving &#8211; probably the same on Mars.<br />
    Cheers,  Regner</p>
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		<title>By: Bob Hyden</title>
		<link>http://blogs.discovermagazine.com/badastronomy/2010/12/07/martian-dunes-under-the-microscope/comment-page-1/#comment-342517</link>
		<dc:creator>Bob Hyden</dc:creator>
		<pubDate>Tue, 07 Dec 2010 16:57:57 +0000</pubDate>
		<guid isPermaLink="false">http://blogs.discovermagazine.com/badastronomy/?p=24568#comment-342517</guid>
		<description>All that is missing are the Worms.</description>
		<content:encoded><![CDATA[<p>All that is missing are the Worms.</p>
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		<title>By: Lupine</title>
		<link>http://blogs.discovermagazine.com/badastronomy/2010/12/07/martian-dunes-under-the-microscope/comment-page-1/#comment-342513</link>
		<dc:creator>Lupine</dc:creator>
		<pubDate>Tue, 07 Dec 2010 16:36:42 +0000</pubDate>
		<guid isPermaLink="false">http://blogs.discovermagazine.com/badastronomy/?p=24568#comment-342513</guid>
		<description>I can almost hear the Syfy channel movie of the week coming....</description>
		<content:encoded><![CDATA[<p>I can almost hear the Syfy channel movie of the week coming&#8230;.</p>
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		<title>By: fernly</title>
		<link>http://blogs.discovermagazine.com/badastronomy/2010/12/07/martian-dunes-under-the-microscope/comment-page-1/#comment-342506</link>
		<dc:creator>fernly</dc:creator>
		<pubDate>Tue, 07 Dec 2010 16:12:27 +0000</pubDate>
		<guid isPermaLink="false">http://blogs.discovermagazine.com/badastronomy/?p=24568#comment-342506</guid>
		<description>You don&#039;t mention the sharp-edged light boulders scattered over the top of the sand dunes. How do boulders get on top of a heap of sand? They had to be there first, right? There must have been some kind of a pavement, a continuous layer of brittle -- lava? sediment? -- which shattered into pieces as the sand was withdrawn from under it. Except that there doesn&#039;t seem to be anywhere near enough white boulders to amount to complete coverage, so there must be a lot of white boulders sunk into the darker sand. And: what started the process of withdrawing the support from under the pavement?</description>
		<content:encoded><![CDATA[<p>You don&#8217;t mention the sharp-edged light boulders scattered over the top of the sand dunes. How do boulders get on top of a heap of sand? They had to be there first, right? There must have been some kind of a pavement, a continuous layer of brittle &#8212; lava? sediment? &#8212; which shattered into pieces as the sand was withdrawn from under it. Except that there doesn&#8217;t seem to be anywhere near enough white boulders to amount to complete coverage, so there must be a lot of white boulders sunk into the darker sand. And: what started the process of withdrawing the support from under the pavement?</p>
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		<title>By: Mike</title>
		<link>http://blogs.discovermagazine.com/badastronomy/2010/12/07/martian-dunes-under-the-microscope/comment-page-1/#comment-342502</link>
		<dc:creator>Mike</dc:creator>
		<pubDate>Tue, 07 Dec 2010 15:52:16 +0000</pubDate>
		<guid isPermaLink="false">http://blogs.discovermagazine.com/badastronomy/?p=24568#comment-342502</guid>
		<description>The spice must flow.</description>
		<content:encoded><![CDATA[<p>The spice must flow.</p>
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