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	Comments on: The Challenge of Space Flight	</title>
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		<title>
		By: Astrostevo		</title>
		<link>https://gregladen.com/blog/2015/01/28/the-challenge-of-space-flight-2/#comment-475260</link>

		<dc:creator><![CDATA[Astrostevo]]></dc:creator>
		<pubDate>Sat, 31 Jan 2015 07:38:29 +0000</pubDate>
		<guid isPermaLink="false">http://scienceblogs.com/gregladen/?p=20841#comment-475260</guid>

					<description><![CDATA[@ ^ Tim : Saw that sundog and SDO launch one on the Bad Astronomy blog ages ago - great clip. 

Sure I&#039;ve forgotten more than one  - there are so many great Space Shuttle clips out there. Movie trailer clips there have worked but weren&#039;t exactly what I was thinking of. Still cool though. 

As for the first paragraph there, I think that&#039; discussion is better left for a more appropriate and relevant thread.]]></description>
			<content:encoded><![CDATA[<p>@ ^ Tim : Saw that sundog and SDO launch one on the Bad Astronomy blog ages ago &#8211; great clip. </p>
<p>Sure I&#8217;ve forgotten more than one  &#8211; there are so many great Space Shuttle clips out there. Movie trailer clips there have worked but weren&#8217;t exactly what I was thinking of. Still cool though. </p>
<p>As for the first paragraph there, I think that&#8217; discussion is better left for a more appropriate and relevant thread.</p>
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		<title>
		By: Tim		</title>
		<link>https://gregladen.com/blog/2015/01/28/the-challenge-of-space-flight-2/#comment-475259</link>

		<dc:creator><![CDATA[Tim]]></dc:creator>
		<pubDate>Fri, 30 Jan 2015 21:19:39 +0000</pubDate>
		<guid isPermaLink="false">http://scienceblogs.com/gregladen/?p=20841#comment-475259</guid>

					<description><![CDATA[I had a thought:  Perhaps we should all pull back and take a look at the &#039;big picture&#039;.  That is, *heating causes expansion*.  Let us step out and measure the lithospheric/atmospheric organism as a whole.  Perhaps it is prudent to proxy up the rotational period of Earth -- To be sure, there is some noise such as earthquakes and Earth staggers like a drunkard.  But even a drunkard finds his way back to the bar with a ceartain well-defined periodicity. 

But, in the spirit of anthropogenic effect upon the atmosphere +rocketry, I find no better example than Atlas V Sonic Boom Meets Sundog: 
https://www.youtube.com/watch?v=SsDEfu8s1Lw]]></description>
			<content:encoded><![CDATA[<p>I had a thought:  Perhaps we should all pull back and take a look at the &#8216;big picture&#8217;.  That is, *heating causes expansion*.  Let us step out and measure the lithospheric/atmospheric organism as a whole.  Perhaps it is prudent to proxy up the rotational period of Earth &#8212; To be sure, there is some noise such as earthquakes and Earth staggers like a drunkard.  But even a drunkard finds his way back to the bar with a ceartain well-defined periodicity. </p>
<p>But, in the spirit of anthropogenic effect upon the atmosphere +rocketry, I find no better example than Atlas V Sonic Boom Meets Sundog:<br />
<a href="https://www.youtube.com/watch?v=SsDEfu8s1Lw" rel="nofollow ugc">https://www.youtube.com/watch?v=SsDEfu8s1Lw</a></p>
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		<title>
		By: Tim		</title>
		<link>https://gregladen.com/blog/2015/01/28/the-challenge-of-space-flight-2/#comment-475258</link>

		<dc:creator><![CDATA[Tim]]></dc:creator>
		<pubDate>Fri, 30 Jan 2015 20:32:54 +0000</pubDate>
		<guid isPermaLink="false">http://scienceblogs.com/gregladen/?p=20841#comment-475258</guid>

					<description><![CDATA[This one is much more beautiful, anyways (Rodger, Overcoat):
https://www.youtube.com/watch?v=N2srIjpsYaU]]></description>
			<content:encoded><![CDATA[<p>This one is much more beautiful, anyways (Rodger, Overcoat):<br />
<a href="https://www.youtube.com/watch?v=N2srIjpsYaU" rel="nofollow ugc">https://www.youtube.com/watch?v=N2srIjpsYaU</a></p>
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		<title>
		By: Tim		</title>
		<link>https://gregladen.com/blog/2015/01/28/the-challenge-of-space-flight-2/#comment-475257</link>

		<dc:creator><![CDATA[Tim]]></dc:creator>
		<pubDate>Fri, 30 Jan 2015 20:26:55 +0000</pubDate>
		<guid isPermaLink="false">http://scienceblogs.com/gregladen/?p=20841#comment-475257</guid>

					<description><![CDATA[I don&#039;t begin to fathom what happened to my link, Tim #13, but it was supposed to be a trailor to Eric Steven Stahl&#039;s Final Approach and the &#039;black project&#039; nature of test pilots:
https://www.youtube.com/watch?v=YCIDBBEOz3o]]></description>
			<content:encoded><![CDATA[<p>I don&#8217;t begin to fathom what happened to my link, Tim #13, but it was supposed to be a trailor to Eric Steven Stahl&#8217;s Final Approach and the &#8216;black project&#8217; nature of test pilots:<br />
<a href="https://www.youtube.com/watch?v=YCIDBBEOz3o" rel="nofollow ugc">https://www.youtube.com/watch?v=YCIDBBEOz3o</a></p>
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		<title>
		By: Tim		</title>
		<link>https://gregladen.com/blog/2015/01/28/the-challenge-of-space-flight-2/#comment-475256</link>

		<dc:creator><![CDATA[Tim]]></dc:creator>
		<pubDate>Fri, 30 Jan 2015 20:19:47 +0000</pubDate>
		<guid isPermaLink="false">http://scienceblogs.com/gregladen/?p=20841#comment-475256</guid>

					<description><![CDATA[Nice compilations, Astrostevo #10.  I&#039;d still suggest that you may have forgotten one (nice parachute demos in it):
https://www.youtube.com/watch?v=p31VFxkKkA4 

Greg Laden #12,
https://www.youtube.com/watch?v=YCIDBBEOz3o]]></description>
			<content:encoded><![CDATA[<p>Nice compilations, Astrostevo #10.  I&#8217;d still suggest that you may have forgotten one (nice parachute demos in it):<br />
<a href="https://www.youtube.com/watch?v=p31VFxkKkA4" rel="nofollow ugc">https://www.youtube.com/watch?v=p31VFxkKkA4</a> </p>
<p>Greg Laden #12,<br />
<a href="https://www.youtube.com/watch?v=YCIDBBEOz3o" rel="nofollow ugc">https://www.youtube.com/watch?v=YCIDBBEOz3o</a></p>
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		<title>
		By: Greg Laden		</title>
		<link>https://gregladen.com/blog/2015/01/28/the-challenge-of-space-flight-2/#comment-475255</link>

		<dc:creator><![CDATA[Greg Laden]]></dc:creator>
		<pubDate>Fri, 30 Jan 2015 17:17:24 +0000</pubDate>
		<guid isPermaLink="false">http://scienceblogs.com/gregladen/?p=20841#comment-475255</guid>

					<description><![CDATA[I would like to see numbers comparing high performance jets (fighter jets, etc.), the space shuttle, and more mundane and very safe airliners.]]></description>
			<content:encoded><![CDATA[<p>I would like to see numbers comparing high performance jets (fighter jets, etc.), the space shuttle, and more mundane and very safe airliners.</p>
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		<title>
		By: Christopher Winter		</title>
		<link>https://gregladen.com/blog/2015/01/28/the-challenge-of-space-flight-2/#comment-475254</link>

		<dc:creator><![CDATA[Christopher Winter]]></dc:creator>
		<pubDate>Fri, 30 Jan 2015 16:58:49 +0000</pubDate>
		<guid isPermaLink="false">http://scienceblogs.com/gregladen/?p=20841#comment-475254</guid>

					<description><![CDATA[Yes, the space shuttle was a magnificent vehicle, and was used to accomplish great things. But still, it was not adequately safe &#8212; by design, because the government skimped on development funds. The original request was for $12 billion; the Nixon administration granted $5.15 billion. (With overruns, final cost was $6.74 billion.)

The original concept was like what Virgin Galactic is doing, but on a somewhat larger scale: A winged first stage would carry the orbiter to about 50,000 feet, then release it to climb to orbit. This orbiter would have been smaller, more of a &quot;people-mover&quot; than a cargo hauler. The system would have been fully reusable.

&lt;a href=&quot;http://www.astronautix.com/lvs/shuttle.htm&quot; rel=&quot;nofollow&quot;&gt;Mark Wade&#039;s Encyclopedia Astronautica&lt;/A&gt; says:

&quot;The final shortcoming was that the shuttle was designed as if it had the inherent operating safety of an airliner. It was not equipped with any provision for crew rescue in case of booster failure during ascent to orbit, or being stranded in orbit, or structural failure during re-entry. The crew was not even provided with spacesuits, despite the lessons of the Soviet space program. This seemed an extraordinary act of engineering hubris, given that contemporary military aircraft were equipped with pressure suits and ejection seats. But the weight problem also meant that there was no margin for crew safety measures without (to NASA) unacceptable impact to the net payload.&quot;

There&#039;s a great deal more to the shuttle safety story, of course. I won&#039;t belabor the point here. Just remember it as one more lesson in the high cost of short-sightedness.]]></description>
			<content:encoded><![CDATA[<p>Yes, the space shuttle was a magnificent vehicle, and was used to accomplish great things. But still, it was not adequately safe &mdash; by design, because the government skimped on development funds. The original request was for $12 billion; the Nixon administration granted $5.15 billion. (With overruns, final cost was $6.74 billion.)</p>
<p>The original concept was like what Virgin Galactic is doing, but on a somewhat larger scale: A winged first stage would carry the orbiter to about 50,000 feet, then release it to climb to orbit. This orbiter would have been smaller, more of a &#8220;people-mover&#8221; than a cargo hauler. The system would have been fully reusable.</p>
<p><a href="http://www.astronautix.com/lvs/shuttle.htm" rel="nofollow">Mark Wade&#8217;s Encyclopedia Astronautica</a> says:</p>
<p>&#8220;The final shortcoming was that the shuttle was designed as if it had the inherent operating safety of an airliner. It was not equipped with any provision for crew rescue in case of booster failure during ascent to orbit, or being stranded in orbit, or structural failure during re-entry. The crew was not even provided with spacesuits, despite the lessons of the Soviet space program. This seemed an extraordinary act of engineering hubris, given that contemporary military aircraft were equipped with pressure suits and ejection seats. But the weight problem also meant that there was no margin for crew safety measures without (to NASA) unacceptable impact to the net payload.&#8221;</p>
<p>There&#8217;s a great deal more to the shuttle safety story, of course. I won&#8217;t belabor the point here. Just remember it as one more lesson in the high cost of short-sightedness.</p>
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		<title>
		By: Astrostevo		</title>
		<link>https://gregladen.com/blog/2015/01/28/the-challenge-of-space-flight-2/#comment-475253</link>

		<dc:creator><![CDATA[Astrostevo]]></dc:creator>
		<pubDate>Fri, 30 Jan 2015 07:55:25 +0000</pubDate>
		<guid isPermaLink="false">http://scienceblogs.com/gregladen/?p=20841#comment-475253</guid>

					<description><![CDATA[The loss of &lt;i&gt;Challenger&lt;/i&gt; one of my early memories and one even earlier one was sitting watching for the very first shuttle flight with astronauts aboard - staying up for hours until it was scrubbed for a computer glitch but just in awe of this wonderful new spaceplane. 

I think the Space Shuttles were wonders of the modern world and behind only the &lt;i&gt;Apollo-Saturn V&lt;/i&gt; craft as the greatest thing humans have ever built. 

A couple of clips showing why I think is so  :

https://www.youtube.com/watch?v=II7QBLt36xo

A tribute putting the Space Shuttle missions in context with everyone of the 135 flights included in chronological order. (But all in a mere eight minutes.) &lt;i&gt;Challenger&#039;s&lt;/i&gt; loss and Reaguns excellent memorial speech following it at the 2 minutes 50 seconds mark.  

This is another tribute clip showing the details of one launch (STS-129 &lt;i&gt;Atlantis&lt;/i&gt;) in all its splendour :  

https://www.youtube.com/watch?v=ewLLBalvehg 

Which I could watch a thousand and fifty plus times and never get sick of. 

Oh, and just one more because, so durn good -  a night launch (STS-130 &lt;i&gt;Endeavour&lt;/i&gt; orbiter) : 

https://www.youtube.com/watch?v=VEDLASr3QN0 

to enjoy as well. If you haven&#039;t seen these before, well you&#039;re in for a treat - if you have, well they&#039;re definitely worth viewing again. About my all-time fave youtube clips and what a spacecraft we used to have.  

I hope we see its like - and better still - again in my lifetime.

*** 

&quot;But out of the whirlwind came a silent bird from the stars, a symbol of our ability to work with nature, to use our intelligence and within the limitations of our world, to do great things.&quot; 
- David Levy on witnessing the 4th landing of the Space Shuttle&lt;i&gt; Columbia&#039;&lt;/i&gt;, Page 28, &#039;Astronomy&#039; magazine October 1982.]]></description>
			<content:encoded><![CDATA[<p>The loss of <i>Challenger</i> one of my early memories and one even earlier one was sitting watching for the very first shuttle flight with astronauts aboard &#8211; staying up for hours until it was scrubbed for a computer glitch but just in awe of this wonderful new spaceplane. </p>
<p>I think the Space Shuttles were wonders of the modern world and behind only the <i>Apollo-Saturn V</i> craft as the greatest thing humans have ever built. </p>
<p>A couple of clips showing why I think is so  :</p>
<p><a href="https://www.youtube.com/watch?v=II7QBLt36xo" rel="nofollow ugc">https://www.youtube.com/watch?v=II7QBLt36xo</a></p>
<p>A tribute putting the Space Shuttle missions in context with everyone of the 135 flights included in chronological order. (But all in a mere eight minutes.) <i>Challenger&#8217;s</i> loss and Reaguns excellent memorial speech following it at the 2 minutes 50 seconds mark.  </p>
<p>This is another tribute clip showing the details of one launch (STS-129 <i>Atlantis</i>) in all its splendour :  </p>
<p><a href="https://www.youtube.com/watch?v=ewLLBalvehg" rel="nofollow ugc">https://www.youtube.com/watch?v=ewLLBalvehg</a> </p>
<p>Which I could watch a thousand and fifty plus times and never get sick of. </p>
<p>Oh, and just one more because, so durn good &#8211;  a night launch (STS-130 <i>Endeavour</i> orbiter) : </p>
<p><a href="https://www.youtube.com/watch?v=VEDLASr3QN0" rel="nofollow ugc">https://www.youtube.com/watch?v=VEDLASr3QN0</a> </p>
<p>to enjoy as well. If you haven&#8217;t seen these before, well you&#8217;re in for a treat &#8211; if you have, well they&#8217;re definitely worth viewing again. About my all-time fave youtube clips and what a spacecraft we used to have.  </p>
<p>I hope we see its like &#8211; and better still &#8211; again in my lifetime.</p>
<p>*** </p>
<p>&#8220;But out of the whirlwind came a silent bird from the stars, a symbol of our ability to work with nature, to use our intelligence and within the limitations of our world, to do great things.&#8221;<br />
&#8211; David Levy on witnessing the 4th landing of the Space Shuttle<i> Columbia&#8217;</i>, Page 28, &#8216;Astronomy&#8217; magazine October 1982.</p>
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		<title>
		By: Brainstorms		</title>
		<link>https://gregladen.com/blog/2015/01/28/the-challenge-of-space-flight-2/#comment-475252</link>

		<dc:creator><![CDATA[Brainstorms]]></dc:creator>
		<pubDate>Fri, 30 Jan 2015 02:30:39 +0000</pubDate>
		<guid isPermaLink="false">http://scienceblogs.com/gregladen/?p=20841#comment-475252</guid>

					<description><![CDATA[Paul, keep in mind that in order to climb the steep climb out of Earth&#039;s &quot;gravity well&quot;, astronauts must ride atop a &quot;continuously and slowly exploding bomb&quot; (with the bomb&#039;s blast being entirely directed downwards, of course).  

In the case of the Saturn V that took men to the moon, this &quot;bomb&quot; weighed 2.5 million kilograms (RP1+LOX) and had the wallop of a small atomic bomb (0.5 to 1 kiloton of TNT).

So, while &quot;it can&#039;t blow up!&quot;, it gets &quot;blown upwards&quot; for several minutes -- until the craft has been accelerated to 17,000 mph on reaching orbit.

The Saturn V F1 main engines are a most amazing engineering feat.  The combined power output of the five F1 engines of the Saturn V first stage was 60 gigawatts -- nearly equivalent to the peak electricity demand of the United Kingdom.

Just the gas generator alone on the F1 produced about 31,000 pounds of thrust, more than an F16 fighter&#039;s engine running at full afterburner.  This auxiliary engine was used to drive a turbine producing 55,000 shaft horsepower for pumping fuel &#038; oxidizer into the combustion chamber.  Note that that was 55,000 horsepower just to run the F1&#039;s pumps; the F1 itself (if you could rate rocket engines this way) produced the equivalent of something like 32 million horsepower.

It takes a lot of guts to trust that to hold together for 11-12 minutes to get into Earth orbit.  (Then they had to trust the rest of the craft to keep them safe &#038; alive for several days -- and get them home again.)]]></description>
			<content:encoded><![CDATA[<p>Paul, keep in mind that in order to climb the steep climb out of Earth&#8217;s &#8220;gravity well&#8221;, astronauts must ride atop a &#8220;continuously and slowly exploding bomb&#8221; (with the bomb&#8217;s blast being entirely directed downwards, of course).  </p>
<p>In the case of the Saturn V that took men to the moon, this &#8220;bomb&#8221; weighed 2.5 million kilograms (RP1+LOX) and had the wallop of a small atomic bomb (0.5 to 1 kiloton of TNT).</p>
<p>So, while &#8220;it can&#8217;t blow up!&#8221;, it gets &#8220;blown upwards&#8221; for several minutes &#8212; until the craft has been accelerated to 17,000 mph on reaching orbit.</p>
<p>The Saturn V F1 main engines are a most amazing engineering feat.  The combined power output of the five F1 engines of the Saturn V first stage was 60 gigawatts &#8212; nearly equivalent to the peak electricity demand of the United Kingdom.</p>
<p>Just the gas generator alone on the F1 produced about 31,000 pounds of thrust, more than an F16 fighter&#8217;s engine running at full afterburner.  This auxiliary engine was used to drive a turbine producing 55,000 shaft horsepower for pumping fuel &amp; oxidizer into the combustion chamber.  Note that that was 55,000 horsepower just to run the F1&#8217;s pumps; the F1 itself (if you could rate rocket engines this way) produced the equivalent of something like 32 million horsepower.</p>
<p>It takes a lot of guts to trust that to hold together for 11-12 minutes to get into Earth orbit.  (Then they had to trust the rest of the craft to keep them safe &amp; alive for several days &#8212; and get them home again.)</p>
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		<title>
		By: Paul Spring		</title>
		<link>https://gregladen.com/blog/2015/01/28/the-challenge-of-space-flight-2/#comment-475251</link>

		<dc:creator><![CDATA[Paul Spring]]></dc:creator>
		<pubDate>Fri, 30 Jan 2015 01:37:44 +0000</pubDate>
		<guid isPermaLink="false">http://scienceblogs.com/gregladen/?p=20841#comment-475251</guid>

					<description><![CDATA[I remember learning that the Challenger had exploded when I was in 5th grade.  Another kid came up to me at the end of recess and said that the space shuttle had blown up.  I believe that I rather foolishly blurted out something like &quot;It can&#039;t blow up!&quot;  I assumed that because space shuttle missions were becoming fairly common at the time, that they must be very safe and that tragic accidents were very unlikely.  It was a shocking reminder to me of how  dangerous the whole thing really is.  

I also remember getting pretty depressed when Columbia broke apart during reentry in 2003.  I was an adult by then, of course, and a little less naive about the dangers, but there was a sinking feeling of &quot;not again&quot;.]]></description>
			<content:encoded><![CDATA[<p>I remember learning that the Challenger had exploded when I was in 5th grade.  Another kid came up to me at the end of recess and said that the space shuttle had blown up.  I believe that I rather foolishly blurted out something like &#8220;It can&#8217;t blow up!&#8221;  I assumed that because space shuttle missions were becoming fairly common at the time, that they must be very safe and that tragic accidents were very unlikely.  It was a shocking reminder to me of how  dangerous the whole thing really is.  </p>
<p>I also remember getting pretty depressed when Columbia broke apart during reentry in 2003.  I was an adult by then, of course, and a little less naive about the dangers, but there was a sinking feeling of &#8220;not again&#8221;.</p>
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