Click2History - EXPLORING SPACE - THE CRAB NEBULA - Chapter 6

<body link="0000ff" alink="ff0000" vlink="000000" bgcolor=000033> <table width="100%" bgcolor=000033> <tr> <td align=center valign=top> <table width=90% bgcolor=ffffff> <tr> <td align=center valign=top> <tr> <td> <div align=center><p><b><font face="arial, helvetica" size=5 color=000000><b>EXPLORING SPACE</p> <p><font size="4">CHAPTER 6 - THE CRAB NEBULA</b></font></p> </div>  <center> <table width="90%"> <tr> <td align="left" valign="top"> <div align="justify"> <p><font face="arial, helvetica" color="000000" size="3">Observing the night sky, <a target="_blank" href="images/1744_contemporary.story_german.news.article_1744.jpg"><b>in 1744</b></a>, a teenaged boy from Badonviller, France - Charles Messier - saw something unusual. It wasn’t the first time this keenly observant lad had studied the heavens. But on this night, he saw <a target="_blank" href="http://apod.gsfc.nasa.gov/apod/lib/glossary.html#cm"><b>a comet</b></a> which had developed six tails.</p> <p>A contemporary artist <a target="_blank" href="images/recorded_C1743X1.Klinkenberg.comet.of.1744_image.by_unknown.artist.jpg"><b>recorded</b></a> how <a target="_blank" href="images/the_comet_appeared_great.comet.1744_from.w.valentiner.book_kometen.und.meteore_1884.jpg"><b>the comet appeared</b></a> when its <a target="_blank" href="images/head_anatomy.of.comet_courtesy_prof.nick.strobel_lecture.notes_purdue.jpg"><b>head</b></a> was below the horizon. By March 8, 1744, the comet was visible in the predawn sky, its tails resembling a Japanese fan. <a target="_blank" href="images/messier_messier.image_courtesy.v.tech.jpg"><b>Messier</b></a>, for years thereafter, continued to search the sky hoping to see (or discover) more comets.</p> <p>The Frenchman thus grew up with a profound love of astronomy. Observing, and <a target="_blank" href="http://www.seds.org/messier/xtra/history/m-m31_42.html"><b>recording</b></a>,  what he saw in the heavens became a career for him. Astronomers still use <a target="_blank" href="http://www.ngcic.org/dss/dss_messier.asp"><b>“M” designations</b></a>,  based on a catalog <a target="_blank" href="http://www.seds.org/messier/xtra/history/m-cat-i.html"><b> he created</b></a>, to identify deep-sky objects with fixed positions. <a target="_blank" href="http://www.seds.org/messier/xtra/history/m-cat-or.html"><b>His list</b></a> includes such things as “<a target="_blank" href="http://apod.gsfc.nasa.gov/apod/lib/glossary.html"><b>fuzzy</b></a>” non-comets known as nebulae. M1 (or, Messier 1), for example, is another name for the Crab Nebula.</p> <p> <a target="_blank" href="http://www.nasa.gov/multimedia/imagegallery/image_feature_567.html"><b>Observed</b></a> by <a target="_blank" href="http://www.seds.org/messier/more/m001_sn.html"><b>Chinese astronomers</b></a> in 1054 AD - when it was an <a target="_blank" href="http://chandra.harvard.edu/photo/2006/4snr/4snr_lg.mov"><b>exploding</b></a> <a target="_blank" href="http://imagine.gsfc.nasa.gov/docs/dictionary.html"><b>supernova</b></a> -  and discovered in 1731 by <a target="_blank" href="http://seds.lpl.arizona.edu/messier/xtra/Bios/bevis.html"><b>John Bevis</b></a> (a British physician and amateur astronomer), the <a target="_blank" href="images/crab_nebula.jpg"><b>Crab Nebula</b></a>  is still one of the <a target="_blank" href="http://science.nasa.gov/NEWHOME/headlines/ast28sep99_1.htm"><b>most studied</b></a> of all objects in the sky. It takes its name from an 1844 (or thereabouts) <a target="_blank" href="images/drawing.jpg"><b>drawing</b></a> by <a target="_blank" href="images/william_parsons_William.Parsons.jpg"><b>William Parsons</b></a>,  the Third Earl of Rosse, who observed it with a <b> <a target="_blank" href="images/36in_reflector.jpg">36-inch reflector</a></b> at his home, <a target="_blank" href="images/birr_castle.jpg"><b>Birr Castle</b></a>,  near Parsonstown, <a target="_blank" href="images/County_Offaly.png"><b>County Offaly</b></a>,  Ireland. Thanks to the Hubble telescope, we can <a target="_blank" href="http://antwrp.gsfc.nasa.gov/apod/ap020920.html"><b>examine it</b></a> in much <a target="_blank" href="images/greater_detail_hubble_nasa.image.taken.1995_HSTI.PR00-15.jpg"><b>greater detail</b></a> than Lord Rosse could have ever imagined - even with his later <b> <a target="_blank" href="images/72in_reflector.jpg">72-inch</a></b>  <a target="_blank" href="images/telescope.jpg"><b>telescope</b></a> which, for nearly a century, was the <a target="_blank" href="http://www.birrcastle.com/"><b>biggest in the world</b></a>.  </p> <p> <a target="_blank" href="http://www.nasa.gov/mission_pages/hubble/multimedia/crab_nebula.html"><b>Hubble’s image</b></a> of the Crab - assembled from twenty-four separate exposures - provides astronomers with <a target="_blank" href="images/incredible_detail_nasa.esa_hubble.image.PIA03606_produced.by_arizona.state.u.jpg"><b>incredible detail</b></a> of <a target="_blank" href="http://chandra.harvard.edu/photo/2006/crab/crab_lg.mov"><b>the nebula</b></a>.  And, because of <a target="_blank" href="http://chandra.harvard.edu/photo/2004/kepler/3_obs_labels_lg.mov"><b>the space telescopes</b></a> (Hubble, <a target="_blank" href="http://www.spitzer.caltech.edu/about/index.shtml"><b>Spitzer</b></a> and <a target="_blank" href="images/chandra_handra.xray.observatory_depicted.in.orbit_nasa.image.gif"><b>Chandra</b></a>),  scientists have learned how the <a target="_blank" href="http://imgsrc.hubblesite.org/hu/db/1996/22/videos/b/formats/low_mpeg.mpg"><b>Crab moves</b></a> (don’t miss this animation) through space: It is <a target="_blank" href="http://hubblesite.org/newscenter/archive/releases/nebula/2002/24/"><b>propelled</b></a>  by a dynamic <a target="_blank" href="http://science.nasa.gov/NEWHOME/help/tutorials/pulsar.htm"><b>pulsar</b></a>  [PULSating stAR] at <a target="_blank" href="http://hubblesite.org/newscenter/archive/releases/1996/22"><b>its core</b></a>. </p> <p>As we continue our virtual <a target="_blank" href="http://chandra.harvard.edu/graphics/resources/illustrations/milkyWay/earth2localgroup_sm.mov"><b>visit to space</b></a>,  let’s examine a few more notable nebulae.</p> </p> </div> <p align="center"><font size="2"><a href="exploring_space_ch5.htm">GO TO LAST CHAPTER</a>   <a href="exploring_space_ch1.htm">BACK TO FIRST CHAPTER</a>   <a href="exploring_space_ch7.htm">GO TO NEXT CHAPTER</a></p> <blockquote><br>  </td> </tr> </table>  </td>  <td align="center" valign="top"> <script type="text/javascript" src="http://www.awesomestories.com/includes/ad_format.js"> </script> <script type="text/javascript" src="http://pagead2.googlesyndication.com/pagead/show_ads.js"> </script> </td>  </tr> </table>  </td> </tr> </table> </body>