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<TITLE>Planetary Talk: Alison Farmer, Tue 12:30 pm CfA</TITLE>
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<P ALIGN=CENTER><SPAN LANG="en-us"><FONT SIZE=2 FACE="Arial">Planetary Science Talk</FONT></SPAN></P>
<P ALIGN=CENTER><SPAN LANG="en-us"><FONT SIZE=2 FACE="Arial">"Ghosts of Saturn: understanding the ring spokes"</FONT></SPAN></P>
<P ALIGN=CENTER><SPAN LANG="en-us"><FONT SIZE=2 FACE="Arial">Alison Farmer</FONT></SPAN></P>
<P ALIGN=CENTER><SPAN LANG="en-us"><FONT SIZE=2 FACE="Arial">Caltech</FONT></SPAN></P>
<P><SPAN LANG="en-us"><FONT SIZE=2 FACE="Arial">The "spokes" in Saturn's rings have eluded explanation since their discovery by the Voyager spacecraft 25 years ago. These mysterious radial dust lanes spring into existence in under five minutes, then fade away in hours as they are sheared apart by the rings' rotation. Unlike most features in the rings, they cannot be explained by gravitation alone, but require electromagnetic forces. I will describe the interesting physics involved, and will propose a new theory of spoke formation that looks set to explain the observations. </FONT></SPAN></P>
<P><SPAN LANG="en-us"><FONT SIZE=2 FACE="Arial">DATE: Dec. 7, Tuesday, 12:30pm</FONT></SPAN>
<BR><SPAN LANG="en-us"><FONT SIZE=2 FACE="Arial">LOCATION:</FONT></SPAN>
<BR><SPAN LANG="en-us"><FONT SIZE=2 FACE="Arial"> Pratt Conference Room (G04)</FONT></SPAN>
<BR><SPAN LANG="en-us"><FONT SIZE=2 FACE="Arial"> Center for Astrophysics</FONT></SPAN>
<BR><SPAN LANG="en-us"><FONT SIZE=2 FACE="Arial"> 60 Garden Street</FONT></SPAN>
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<P><SPAN LANG="en-us"><FONT SIZE=2 FACE="Arial">Maps: </FONT></SPAN><A HREF="http://cfa-www.harvard.edu/images/cfa_60Garden.jpg"><SPAN LANG="en-us"><U><FONT COLOR="#0000FF" SIZE=2 FACE="Arial">http://cfa-www.harvard.edu/images/cfa_60Garden.jpg</FONT></U></SPAN></A><SPAN LANG="en-us"></SPAN>
<BR><SPAN LANG="en-us"></SPAN><A HREF="http://cfa-www.harvard.edu/mapclk.html"><SPAN LANG="en-us"><U><FONT COLOR="#0000FF" SIZE=2 FACE="Arial">http://cfa-www.harvard.edu/mapclk.html</FONT></U></SPAN></A><SPAN LANG="en-us"></SPAN>
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