Difference between revisions of "November 2, 2004"
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| − | + | <td width="50%"><h2><nobr>Offset Moon</nobr></h2></td> | |
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</table> | </table> | ||
<table width="85%" border="0" align="center" cellpadding="6" cellspacing="2"> | <table width="85%" border="0" align="center" cellpadding="6" cellspacing="2"> | ||
| − | + | <tr><td colspan="2" valign="top"><div align="center"> | |
| − | + | <img src="archive/2004/11/images/LPOD-2004-11-02.jpeg" border="0"> | |
| − | + | </div></td> | |
| − | + | </tr> | |
</table> | </table> | ||
<table width="80%" border="0" align="center" cellpadding="8"> | <table width="80%" border="0" align="center" cellpadding="8"> | ||
| − | + | <tr><td><div align="center" class="main_sm">Image Credit: [mailto:pete.lawrence@pbl33.co.uk Pete Lawrence]</p> | |
| − | + | </div></td> | |
| − | + | </tr> | |
| − | + | </table> | |
<br> | <br> | ||
<table class="story" border="0" bgcolor="#FFFFFF" width="90%" cellpadding="10" align="center"><tr><td> | <table class="story" border="0" bgcolor="#FFFFFF" width="90%" cellpadding="10" align="center"><tr><td> | ||
| − | + | <p align="center"><b>Offset Moon</b></p> | |
| − | + | <p align="left">Determination of the distances to the stars and galaxies beyond our own is one of the greatest intellectual triumphs of humanity. Measuring parallax - the movement of a nearby star relative to distant stars - is the foundation of all our knowledge of the size of the universe. But the distance to even the nearest stars is so great that the discovery of stellar parallax was not accomplished until 1838. However, the parallactic offset of a nearby astronomical object like the Moon is much easier to demonstrate. In this composite of two images of the eclipsed Moon, taken simultaneously by Pete Lawrence in England and by Pete Cleary, 5220 km away in Montreal, Canada, shows that the Moon shifted about 1.3 times its diameter or about 40 seconds of arc. These data yield a distance to the Moon of 453,168 km - considerably beyond the correct value of about 384,000 km. Actually this experiment has been done before, by the ancient Greek astronomer Hipparchus, whose error was only 36,000 km - twice as good as my estimate!</p> | |
| − | + | <blockquote><p align="right">— [mailto:tychocrater@yahoo.com Chuck Wood]</blockquote> | |
<p align="left"><p><b>Related Links:</b><br> | <p align="left"><p><b>Related Links:</b><br> | ||
[http://www.digitalsky.org.uk/2004-09/MMVS.jpg Pete's DigitalSky page] | [http://www.digitalsky.org.uk/2004-09/MMVS.jpg Pete's DigitalSky page] | ||
<br>[http://www.mlahanas.de/Greeks/Hipparchus.htm Hipparchus of Rhodes] | <br>[http://www.mlahanas.de/Greeks/Hipparchus.htm Hipparchus of Rhodes] | ||
<p align="left"><b>Tomorrow's LPOD: </b> Looking Down the Chain</p> | <p align="left"><b>Tomorrow's LPOD: </b> Looking Down the Chain</p> | ||
| − | + | </tr> | |
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</table> | </table> | ||
<br> | <br> | ||
<table width="100%" border="0" cellspacing="2" cellpadding="4"> | <table width="100%" border="0" cellspacing="2" cellpadding="4"> | ||
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| − | + | <td><hr></td> | |
| − | + | </tr> | |
| − | + | <tr><td> | |
| − | + | <p align="center" class="main_titles"><b>Author & Editor:</b><br> | |
| − | + | [mailto:tychocrater@yahoo.com Charles A. Wood]</p> | |
| − | + | <p align="center" class="main_titles"><b>Technical Consultant:</b><br> | |
| − | + | [mailto:anthony@perseus.gr Anthony Ayiomamitis]</p> | |
| − | + | <p align="center" class="main_titles"><b>Contact Translator:</b><br> | |
| − | + | [mailto:pablolonnie@yahoo.com.mx" class="one Pablo Lonnie Pacheco Railey] (Es)<br> | |
| − | + | [mailto:chlegrand@free.fr" class="one Christian Legrand] (Fr)</p> | |
| − | + | <p align="center" class="main_titles"><b>[mailto:webuser@observingthesky.org Contact Webmaster]</b></p> | |
| − | + | <p align="center" class="main_titles"><b>A service of:</b><br> | |
| − | + | [http://www.observingthesky.org/" class="one ObservingTheSky.Org]</p> | |
| − | + | <p align="center" class="main_titles"><b>Visit these other PODs:</b> <br> | |
| − | + | [http://antwrp.gsfc.nasa.gov/apod/astropix.html" class="one Astronomy] | [http://www.msss.com/" class="one Mars] | [http://epod.usra.edu/" class="one Earth]</p> | |
| − | + | </td></tr> | |
</table> | </table> | ||
<p> </p> | <p> </p> | ||
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===COMMENTS?=== | ===COMMENTS?=== | ||
Click on this icon [[image:PostIcon.jpg]] at the upper right to post a comment. | Click on this icon [[image:PostIcon.jpg]] at the upper right to post a comment. | ||
Revision as of 18:27, 4 January 2015
Offset Moon
<nobr>Offset Moon</nobr> |
<img src="archive/2004/11/images/LPOD-2004-11-02.jpeg" border="0"> |
Image Credit: Pete Lawrence
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Offset Moon Determination of the distances to the stars and galaxies beyond our own is one of the greatest intellectual triumphs of humanity. Measuring parallax - the movement of a nearby star relative to distant stars - is the foundation of all our knowledge of the size of the universe. But the distance to even the nearest stars is so great that the discovery of stellar parallax was not accomplished until 1838. However, the parallactic offset of a nearby astronomical object like the Moon is much easier to demonstrate. In this composite of two images of the eclipsed Moon, taken simultaneously by Pete Lawrence in England and by Pete Cleary, 5220 km away in Montreal, Canada, shows that the Moon shifted about 1.3 times its diameter or about 40 seconds of arc. These data yield a distance to the Moon of 453,168 km - considerably beyond the correct value of about 384,000 km. Actually this experiment has been done before, by the ancient Greek astronomer Hipparchus, whose error was only 36,000 km - twice as good as my estimate! Related Links: Tomorrow's LPOD: Looking Down the Chain |
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Author & Editor: Technical Consultant: Contact Translator: A service of: Visit these other PODs: |
COMMENTS?
Click on this icon File:PostIcon.jpg at the upper right to post a comment.
