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	<title>polyscience.org &#187; Physics</title>
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	<link>http://polyscience.org</link>
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		<title>Russia plans to mine the moon</title>
		<link>http://polyscience.org/2006/01/russia-helium-3/</link>
		<comments>http://polyscience.org/2006/01/russia-helium-3/#comments</comments>
		<pubDate>Sat, 28 Jan 2006 02:12:31 +0000</pubDate>
		<dc:creator>Rian</dc:creator>
				<category><![CDATA[Physics]]></category>
		<category><![CDATA[Pop culture]]></category>
		<category><![CDATA[Space and astronomy]]></category>

		<guid isPermaLink="false">http://polyscience.org/2006/01/russia-helium-3/</guid>
		<description><![CDATA[I&#8217;d file this particular bit of news under the &#8220;I&#8217;ll believe it when I see it&#8221; section if I had one: the Russian Energia Space Corporation has unveiled plans to open a mine on the moon. Helium-3, a non-radioactive helium isotope, is found in relative abundance on the moon whereas here on Earth, it&#8217;s extremely [...]]]></description>
			<content:encoded><![CDATA[<p>I&#8217;d file this particular bit of news under the &#8220;I&#8217;ll believe it when I see it&#8221; section if I had one: the Russian Energia Space Corporation has <a href="http://news.independent.co.uk/europe/article341273.ece">unveiled plans</a> to open a mine on the moon. Helium-3, a non-radioactive helium isotope, is found in relative abundance on the moon whereas here on Earth, it&#8217;s extremely rare. The isotope is the ideal fuel for a fusion reaction because of its clean decay and relatively harmless byproducts.</p>
<p>Because it is rare on Earth, having a mine on the moon might be economically viable if it weren&#8217;t for one problem: a viable energy-producing fusion reaction has yet to be developed. Nonetheless, Energia will press on with their mining plans: they plan to establish a permanent lunar base by 2015 or 2020. The idea is that when a reactor capable of using Helium-3 is developed, Energia will have the infrastructure already in place to supply the Earth with it. Due to the nature of E=mc^2, Nikolai Sevastyanov, head of Energia, predicts that one ton of the isotope will produce as much energy as 14 millions tons of oil. While I think that&#8217;s being a little overly optimistic, Helium-3 certainly offers more promise than current fossil fuels.</p>
<blockquote><p>&#8220;Ten tons of helium 3 would be enough to meet the yearly energy needs of Russia,&#8221; he added. However, Russia is not the only country interested in the technology. American scientists have expressed interest in helium 3, arguing that one shuttle-load of the isotope would be sufficient to meet US electrical energy needs for a year.</p></blockquote>
<p>Even viewing the figures bandied about with a great deal of skepticism, Helium-3 is certainly a promising theory, if nothing else. Mining in space is an interesting (and old) idea. I can remember discussing how to make space profitable from a private business&#8217;s point of view as far back as elementary school. Naturally, we thought in terms of precious metals: gold, platinum, etc. instead of consumable materials, but I think it&#8217;s a safe bet that as raw materials become increasingly scarce, it won&#8217;t be the relatively useless &#8220;precious&#8221; metals that humanity comes to value, but rather the consumable raw materials that a nation controls that determines their stability. Gold in Fort Knox? How about Helium-3 buried in a mountain somewhere instead.</p>
<p>[tags]Helium-3, Kliper, Energia, lunar base[/tags]</p>
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		<title>They say 2005 was warm&#8230;</title>
		<link>http://polyscience.org/2006/01/2005-scorcher/</link>
		<comments>http://polyscience.org/2006/01/2005-scorcher/#comments</comments>
		<pubDate>Thu, 26 Jan 2006 02:58:23 +0000</pubDate>
		<dc:creator>Rian</dc:creator>
				<category><![CDATA[Physics]]></category>

		<guid isPermaLink="false">http://polyscience.org/2006/01/2005-scorcher/</guid>
		<description><![CDATA[You know there&#8217;s been a lot of talk about climate change lately. There&#8217;s a reason for that. It turns out that 2005 was the warmest year in a century. In order to figure out whether the Earth is cooling or warming, the scientists use temperature data from weather stations on land, satellite measurements of sea [...]]]></description>
			<content:encoded><![CDATA[<p>You know there&#8217;s been a lot of talk about climate change lately. There&#8217;s a reason for that. It turns out that 2005 was the <a href="http://www.eurekalert.org/pub_releases/2006-01/nsfc-2w012406.php">warmest year in a century</a>.</p>
<blockquote><p>In order to figure out whether the Earth is cooling or warming, the scientists use temperature data from weather stations on land, satellite measurements of sea surface temperature since 1982, and data from ships for earlier years.</p></blockquote>
<p>The previous record holder was 1998, when El Ni&ntilde;o was in effect. (Remember that?) 2005 takes the cake without any warmer waters from the eastern Pacific. Thus far the warmest years in order are:</p>
<ol>
<li>2005</li>
<li>1998</li>
<li>2002</li>
<li>2003</li>
<li>2004</li>
</ol>
<p>There is some controversy over whether or not 2005 was actually the warmest year. Data from groups besides NASA did not take into account the Arctic regions, which were warmer this year than in previous years, bumping 2005 into the lead. Climate change has also been to blame for the ridiculous amount of activity this hurricane season, with a <a href="http://arstechnica.com/journals/science.ars/2005/12/31/2256">total of 27 tropical storms</a>.</p>
<p>[tags]climate change, global warming, hurricane season[/tags]</p>
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		<title>On quicksand</title>
		<link>http://polyscience.org/2005/10/on-quicksand/</link>
		<comments>http://polyscience.org/2005/10/on-quicksand/#comments</comments>
		<pubDate>Mon, 03 Oct 2005 02:49:16 +0000</pubDate>
		<dc:creator>Rian</dc:creator>
				<category><![CDATA[Physics]]></category>

		<guid isPermaLink="false">http://polyscience.org/?p=144</guid>
		<description><![CDATA[It&#8217;s funny that I would come across a story about quicksand a few days after watching Blazing Saddles, wondering if quicksand was really the way it&#8217;s always portrayed in movies. It always seemed difficult for me to imagine sand which could collapse quick enough to trap someone. Discovery News is running an article on the [...]]]></description>
			<content:encoded><![CDATA[<p>It&#8217;s funny that I would come across a story about quicksand a few days after watching <a href="http://www.amazon.com/exec/obidos/tg/detail/-/B0001Z4OXS/qid=1128307719/sr=1-1/ref=sr_1_1/102-7718167-0927338?v=glance&#038;s=dvd"><em>Blazing Saddles</em></a>, wondering if quicksand was really the way it&#8217;s always portrayed in movies. It always seemed difficult for me to imagine sand which could collapse quick enough to trap someone.</p>
<p>Discovery News is running an article on the <a href="http://dsc.discovery.com/news/afp/20050926/quicksand.html">physics of quicksand</a>, and it&#8217;s interesting.</p>
<blockquote><p>On the other hand, it loses this viscosity very quickly in response to stress. A moving object in the sand causes it to liquefy swiftly, as the sand heads towards the bottom and the upper layers become runny. </p>
<p>The settling sand then becomes so compact that it is impossible for material with the density of a human body to become completely submerged. </p>
<p>So an ensnared cowboy should take solace in that he won&#8217;t drown, the study suggests. On the other hand, he is likely to stay there for a long time, for even the most muscular help won&#8217;t get him out. </p>
<p>The dense sand so clumps around the lower limbs that just to haul out a foot requires a force of 100,000 Newtons, about the same as that needed to lift a medium-sized car.</p></blockquote>
<p>Holy cow. The whole article is worth a read. (It&#8217;s brief.)</p>
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		<title>A supernova wiped out the large mammoths?</title>
		<link>http://polyscience.org/2005/09/supernova-wiped-out-mammoths/</link>
		<comments>http://polyscience.org/2005/09/supernova-wiped-out-mammoths/#comments</comments>
		<pubDate>Fri, 30 Sep 2005 11:53:57 +0000</pubDate>
		<dc:creator>Rian</dc:creator>
				<category><![CDATA[Biology]]></category>
		<category><![CDATA[Physics]]></category>
		<category><![CDATA[Space and astronomy]]></category>

		<guid isPermaLink="false">http://polyscience.org/?p=141</guid>
		<description><![CDATA[Color me skeptical, but this story on Discovery Channel News suggests that a supernova was the ultimate cause for many of the large animals that are extinct today: mammoths, mastodons, sabre-toothed tigers, etc. Apparently the key piece indicating the explosion is a set of 34,000-year-old mammoth tusks riddled with tiny craters. The researchers believe that [...]]]></description>
			<content:encoded><![CDATA[<p>Color me skeptical, but <a href="http://dsc.discovery.com/news/briefs/20050926/mammoth.html">this story on Discovery Channel News</a> suggests that a supernova was the ultimate cause for many of the large animals that are extinct today: mammoths, mastodons, sabre-toothed tigers, etc. Apparently the key piece indicating the explosion is a set of 34,000-year-old mammoth tusks riddled with tiny craters.</p>
<blockquote><p>The researchers believe that in the sequence of events following the supernova, first, the iron-rich grains emitted from the explosion shot into the tusks. Whatever caused the craters had to have been traveling around 6,214 miles per second, and no other natural phenomenon explains the damage, they said.</p></blockquote>
<p>They think the supernova exploded 250 light-years away from Earth, which would account for the 7,000-year delay before the tusk grain pelting. It would have taken that long for the supernova materials to have showered Earth.</p>
<p>These iron grains were traveling at exactly 6,214 miles per second, I&#8217;m sure. Somehow the leap from tiny craters in mammoth tusks to a supernova to iron grains traveling at exactly 6,214 miles per second seems a little&#8230; I dunno&#8230; HUGE to me.</p>
<p>Then there were storms similar to those in The Day After Tomorrow caused by a comet-like shower of debris (similar to a nuclear winter, I would suspect) which caused superheated hurricanal winds in the atmosphere that then rolled across North America</p>
<p>The debris is supposed to have killed all the large animals but saved the small animals who escaped by going underground.</p>
<blockquote><p>In addition to the tusk evidence, the scientists said arrowheads from North America&#8217;s prehistoric Clovis culture, which went extinct around 13,500-13,000 years ago, Icelandic marine sediment, as well as sediment from nine 13,000-year-old sites in North America, contain higher-than-normal amounts of radiation in the form of potassium-40 levels. </p>
<p>[...]</p>
<p>Magnetic particles also were unearthed at the sites. Analysis of these particles revealed they are rich in titanium, iron, manganese, vanadium, rare-earth elements, thorium and uranium. </p>
<p>These elements all are common in moon rocks and lunar meteorites, so the researchers think the materials provide additional evidence that North America was bombarded 13,000 years ago by material originating from space.</p></blockquote>
<p>I buy the space-bombardment, but I have difficulty making the leap from tiny tusk craters to superheated hurricanes destroying North America. A lot of scientists seem excited about the idea, so maybe I&#8217;m the only one having this difficulty. I would think that looking at the night sky would show up a location 250 light years from Earth where a supernova could have occurred. A black hole, perhaps. I&#8217;d like to hear from the astrophysicists now, I think, because frankly, this theory sounds a little like an <a href="http://www.amazon.com/exec/obidos/tg/detail/-/B00006CXHU/qid=1128045314/sr=1-1/ref=sr_1_1/103-8795942-3535834?v=glance&#038;s=dvd"><em>Ice Age</em></a> sequel than a solid scientific theory.</p>
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		<title>Degassing two killer lakes isn&#8217;t working so well</title>
		<link>http://polyscience.org/2005/09/killer-lakes/</link>
		<comments>http://polyscience.org/2005/09/killer-lakes/#comments</comments>
		<pubDate>Wed, 28 Sep 2005 04:13:24 +0000</pubDate>
		<dc:creator>Rian</dc:creator>
				<category><![CDATA[Physics]]></category>
		<category><![CDATA[Sociology]]></category>

		<guid isPermaLink="false">http://polyscience.org/?p=137</guid>
		<description><![CDATA[Lakes Nyos and Monoun in Cameroon are building towards releasing toxic gases again. In the 1980s, the two lakes vented their payload and killed nearly 1800 people. Primarily carbon dioxide, the concentrations in the lake are building again, despite having a ventilation pipes installed in 2001 to prevent this sort of thing from happening again. [...]]]></description>
			<content:encoded><![CDATA[<p>Lakes Nyos and Monoun in Cameroon are building towards releasing toxic gases again. In the 1980s, the two lakes vented their payload and killed nearly 1800 people. Primarily carbon dioxide, the concentrations in the lake are <a href="http://www.newscientist.com/article.ns?id=dn8053">building again</a>, despite having a ventilation pipes installed in 2001 to prevent this sort of thing from happening again. The gas is created by volcanic activity beneath the lakes, and although the pipes are working, scientists fear that they are not working fast enough.</p>
<p>They speculate that adding more pipes could help alleviate the problem, and that current pipes will only remove an estimated 10% of the total gas in the next year.</p>
<blockquote><p>“This slow removal extends the present risk to local populations,” says Kling. “Our model indicates that 75-99% of the gas remaining would be removed by 2010 with two pipes in Monoun and five pipes in Nyos, substantially reducing the risks.”</p></blockquote>
<p>There are two ways of de-gassing the lakes, the current method in place at the two lakes is the &#8220;<a href="http://perso.wanadoo.fr/mhalb/nyos/project/indexproj.htm">autonomous soda fountain</a>&#8221; method which consists of a vertical pipe between the lake bottom and the surface. A small pump raises the water in the pipe up to a level where it becomes saturated with gas, which lightens the water column. The saturated water rises to the surface creating a spectacular 68-foot water fountain which can be turned on and off at will via radio from shore. Once the process is primed, there is no need for the pump to operate because the process perpetuates itself.</p>
<p>There are three &#8220;killer lakes&#8221; in the world that release gases: lakes Nyos and Monoun, and Lake Kivu in Rwanda. Lake Kivu differs in that its killer gas is made up of carbon dioxide and methane. Because methane is valuable, several commercial enterprises have undertaken <a href="http://www.mbendi.co.za/avec/casestudies/cs_08.htm">harvesting the methane</a> from the lake to make some money as well as prevent deadly &#8220;overturn&#8221; which seems to occur once every 1,000 years or so, which kills all of the wildlife in the lake, and around the lake. Lake Kivu is much larger than Nyos and Monoun, but its circumstances are a little bit different in that harvesting the gas is a profitable &#8212; as well as life-saving &#8212; enterprise.</p>
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		<title>Building a space elevator</title>
		<link>http://polyscience.org/2005/09/space-elevator/</link>
		<comments>http://polyscience.org/2005/09/space-elevator/#comments</comments>
		<pubDate>Tue, 27 Sep 2005 14:01:28 +0000</pubDate>
		<dc:creator>Rian</dc:creator>
				<category><![CDATA[Physics]]></category>
		<category><![CDATA[Space and astronomy]]></category>

		<guid isPermaLink="false">http://polyscience.org/?p=136</guid>
		<description><![CDATA[Once again, the civilian sector is moving into space. Several months ago saw Burt Rutan &#038; Co. win the X-Prize, and now another private group is working on constructing a space elevator. Their proof of concept model successfully tested a robot climber which climbed up a ribbon simulating a future nanowire space elevator. The test, [...]]]></description>
			<content:encoded><![CDATA[<p>Once again, the civilian sector is moving into space. Several months ago saw Burt Rutan &#038; Co. win the X-Prize, and now another private group is <a href="http://www.msnbc.msn.com/id/9454786/">working on constructing a space elevator</a>. Their proof of concept model successfully tested a robot climber which climbed up a ribbon simulating a future nanowire space elevator.</p>
<p>The test, which was conducted in a secret location (for privacy and safety&#8217;s sake) in Eastern Washington, involved a 12&#8242; diameter balloon, a 23lb robot climber, and a long foot ribbon made of composite fiberglass. The lifter is the LiftPort Group&#8217;s 18th version(!), and its best altitude was 1,000 feet</p>
<blockquote><p>Laine said that the Federal Aviation Administration has been very supportive and helpful in orchestrating their test flights. </p>
<p>&#8220;We are cleared up to 1 mile high, off of a tethered helium balloon,&#8221; Laine said. &#8220;Our series of tests are designed to gain in altitude as we go, as we test our communications, range sensors, global positioning system satellite gear, along with temperature and camera systems.&#8221;</p></blockquote>
<p>The company has also created LiftPort Nanotech in New Jersey focusing on mass production of nanotubes to eventually create the super-strong thread of a space elevator.</p>
<p>Along the same lines, the Spaceward Foundation of Mountain View, CA has announced a competition in two parts: the Tether Challenge to create strong nanotube-based materials and the Beam Power Challenge which is a competition to create a climber that can climb 200 feet powered by a high-intensity light source. The competition is sponsored by the <a href="http://www.space.com/news/050323_centennial_challenge.html">NASA Centennial Challenges program</a>.</p>
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		<title>Supermassive black hole powers the Andromeda galaxy</title>
		<link>http://polyscience.org/2005/09/andromeda-black-hole/</link>
		<comments>http://polyscience.org/2005/09/andromeda-black-hole/#comments</comments>
		<pubDate>Sun, 25 Sep 2005 12:36:07 +0000</pubDate>
		<dc:creator>Rian</dc:creator>
				<category><![CDATA[Physics]]></category>
		<category><![CDATA[Space and astronomy]]></category>

		<guid isPermaLink="false">http://polyscience.org/?p=130</guid>
		<description><![CDATA[A massive black hole with the mass of 140,000,000 suns(!) has been found at the center of the Andromeda galaxy, surrounding by fast-orbiting, hot, blue stars similar to Sirius, which is the brightest visible star in our own night sky. These blue stars are orbiting so quickly that their speed can only be explained by [...]]]></description>
			<content:encoded><![CDATA[<p>A massive black hole with the mass of 140,000,000 suns(!) <a href="http://dsc.discovery.com/news/briefs/20050919/andromeda.html">has been found</a> at the center of the Andromeda galaxy, surrounding by fast-orbiting, hot, blue stars similar to Sirius, which is the brightest visible star in our own night sky. These blue stars are orbiting so quickly that their speed can only be explained by the existence of a massive black hole. By calculating the speed of their orbit, scientists have determined the mass of what they  are orbiting.</p>
<p>It has been suspected that a black hole existed at the center of Andromeda, but other theories have suggested that it was inhabited by dead and dying brown dwarf stars. However, the measurement of the speed of the blue stars&#8217; orbit has laid that theory to rest. The measurements were made using data from a now-defunct spectrometer on the Hubble Space Telescope &#8212; which is an unusual use for a spectrometer.</p>
<p>It is suspected that there are 35 other galaxies with supermassive black holes at their centers, though only two have actually been confirmed: our own Milky Way, and M106. It is doubtful whether black holes in the other 35 galaxies will ever be confirmed because they are so far away. (Though personally I believe determinations will be made in the next 50 years, with the rate that technology is progressing.) Andromeda is the closest galaxy to our own, and it is easier to look into than the Milky Way due to its orientation: we are on the outskirts of the Milky Way, and looking towards the center of our galaxy is difficult. Because Andromeda is removed somewhat, studying it is easier.</p>
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		<title>NIST atomic clock gets more accurate</title>
		<link>http://polyscience.org/2005/09/atomic-clock-accuracy/</link>
		<comments>http://polyscience.org/2005/09/atomic-clock-accuracy/#comments</comments>
		<pubDate>Sun, 25 Sep 2005 11:56:10 +0000</pubDate>
		<dc:creator>Rian</dc:creator>
				<category><![CDATA[Physics]]></category>

		<guid isPermaLink="false">http://polyscience.org/?p=129</guid>
		<description><![CDATA[Most clocks get progressively less accurate as time goes on, the only deviance from this near-universal truth is by how much. However the atomic fountain clock has gotten more accurate with time. By the latest measurement, the clock will neither gain nor lose a second in 60 million years, with a certainty of 0.53e-15. Some [...]]]></description>
			<content:encoded><![CDATA[<p>Most clocks get progressively less accurate as time goes on, the only deviance from this near-universal truth is by how much. However the atomic fountain clock has gotten more accurate with time. By the latest measurement, the clock will neither gain nor lose a second in 60 million years, with a certainty of 0.53e-15. Some of you might recall that atomic clocks generally lose roughly one second every few million years. Atomic clocks function by measuring the oscillation of cesium atoms, which oscillates roughly 9 billion times per second.</p>
<p>The NIST-F1&#8242;s improved accuracy comes from better lasers, software and equipment; the cesium atoms being spread over a larger space which reduces the frequency of particle interaction; and the ability to control the magnetic fields within the clock, and are able to quantify and compensate for them.</p>
<p>The usefulness of a more accurate atomic clock seems somewhat unclear to me. The <a href="http://www.eurekalert.org/pub_releases/2005-09/nios-naf092305.php">press release</a> states that the improved accuracy allows for better precision: navigation systems, telecommunications networks, and wireless and deep space communications all may benefit, though I question whether the &#8220;benefit&#8221; has any measurable, real-world impact.</p>
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		<title>The cheerio effect</title>
		<link>http://polyscience.org/2005/09/cheerio-effect/</link>
		<comments>http://polyscience.org/2005/09/cheerio-effect/#comments</comments>
		<pubDate>Sat, 24 Sep 2005 10:53:07 +0000</pubDate>
		<dc:creator>Rian</dc:creator>
				<category><![CDATA[Physics]]></category>

		<guid isPermaLink="false">http://polyscience.org/?p=126</guid>
		<description><![CDATA[If you&#8217;re like me, you probably used to play with your cheerios as a means of stalling in the morning before going to school. I used to play with my cheerios and see what sorts of patterns I could make without actually touching them. I used to do the same with bubbles in my juice. [...]]]></description>
			<content:encoded><![CDATA[<p>If you&#8217;re like me, you probably used to play with your cheerios as a means of stalling in the morning before going to school. I used to play with my cheerios and see what sorts of patterns I could make without actually touching them. I used to do the same with bubbles in my juice. I used to try to influence them and then figure out why they were behaving the way they did. Apparently I wasn&#8217;t the only one who was fascinated by liquids and the way they interacted with solids because there&#8217;s a new study that is due to be published in the American Journal of Physics that explains the physics of cheerios a bowl of milk. I always used to like eating cheerios because they didn&#8217;t break down into particulate matter, and I never had to hunt for the last cheerio in a bowl full of milk. Now I know why.</p>
<p>The clumping effect is a result of a combination of surface tension, buoyancy, and gravity. Cheerios float, but they also press down on the surface of the milk, creating little concave indentations in the surface. So when two cheerios float near one another, they &#8220;fall down&#8221; each other&#8217;s cave, creating the appearance of an attractive force.</p>
<p>Cheerios on the edge of a bowl of milk are sitting atop the meniscus of the milk, and when there&#8217;s a chain of them along the edge, it&#8217;s because they&#8217;re atop the meniscus, forming their own little concave indentations making them seem sticky.</p>
<p>From <a href="http://msnbc.msn.com/id/9425907/">MSNBC</a>.</p>
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		<title>The Space Cycle</title>
		<link>http://polyscience.org/2005/09/space-cycle/</link>
		<comments>http://polyscience.org/2005/09/space-cycle/#comments</comments>
		<pubDate>Sat, 17 Sep 2005 02:11:25 +0000</pubDate>
		<dc:creator>Rian</dc:creator>
				<category><![CDATA[Medicine]]></category>
		<category><![CDATA[Physics]]></category>

		<guid isPermaLink="false">http://polyscience.org/?p=113</guid>
		<description><![CDATA[A month ago to the day, I wrote about Sergei Krikalev&#8217;s record-setting time in space: 748 days. I also mentioned that it was at possible detriment to his health: being in a &#8220;zero G&#8221; environment takes its toll on the body in numerous way. Chief among them is bone density and muscle loss. The body [...]]]></description>
			<content:encoded><![CDATA[<p>A month ago to the day, I wrote about Sergei Krikalev&#8217;s <a href="http://polyscience.org/2005/08/748-days-in-space/">record-setting time in space</a>: 748 days. I also mentioned that it was at possible detriment to his health: being in a &#8220;zero G&#8221; environment takes its toll on the body in numerous way. Chief among them is bone density and muscle loss. The body doesn&#8217;t need the excess bone and muscle tissue to support itself in space so it gets rid of it to be more efficient. Obviously this poses some problems when you return to Earth and are unable to stand up or otherwise function normally, so astronauts on long space missions exercise to minimize the impact to their health.</p>
<p>Typically, they exercise on a treadmill, running with elastic suspender-like contraptions to simulate gravity in a crude way. Now a new device, called the <a href="http://www.nsbri.org/NewsPublicOut/Release.epl?r=86">Space Cycle</a>, being developed at UC Irvine utilizes artificial gravity through centrifugal forces. The device scales from 1G to 5Gs, and allows two people to exercise on it simultaneously. One on an elliptical machine or bike, and the other doing a sort of squat. The one pedalling causes the cetrifuge to spin (<a href="http://www.nsbri.org/NewsPublicOut/Squat_Movie_05_17_05.mov">video</a>).</p>
<p>It&#8217;s a cool idea, though looking at the video leads me to believe that unless the device is shrunk somewhat, it&#8217;ll be too large to fit inside current space quarters. Honestly, I&#8217;m not sure how much more it could be reduced, but its radius seems too great to store easily. Another problem with the cycle is that in &#8220;zero gravity,&#8221; any spinning object can cause torque on the vessel as well, so a way of counteracting this torque will have to be developed.</p>
<p>In any case, it&#8217;s nice to see some progress being made towards allowing astronauts and cosmonauts to stay in space for extended periods of time. Along the same vein, I mention in the writeup that I wondered about drugs like Fosamax and other bisphosphonates being used to prevent bone loss. Dr. Jay Buckey, a doctor at Dartmouth Medical School returned my email, stating that while such drugs had been investigated in bed rest studies (physiological analogs), they are not actually utilized, and that several people in space have reduced their bone density loss to minimal levels simply by exercising.</p>
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