document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=548404>Question 548404</A>: <I><SPAN STYLE=\"word-break: break-all;\"> I have an astronomy program that provides information on known comets.  They provide only two pieces of information:  Perhelion and eccentricity.\r<BR>\n" );
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document.write( " I have gone through a number of books and web pages both for astronomy problems and math problems trying to find out how to find out the length of the major axis.\r<BR>\n" );
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document.write( "I am not very good at working with advanced math (though I have studied some that I needed to use).  Please help me with this.  Thank you </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #356972 by </B><A HREF=/tutors/aboutme.mpl?userid=stanbon><B>stanbon(75887)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=stanbon><IMG SRC=http://www.algebra.com/images/aboutme-small.gif BORDER=0 alt=\"About Me\" VALIGN=MIDDLE></A>&nbsp;<IMG SRC=http://www.algebra.com/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=356972\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\">  I have an astronomy program that provides information on known comets. They provide only two pieces of information: Perhelion and eccentricity. <BR>\n" );
document.write( "I have gone through a number of books and web pages both for astronomy problems and math problems trying to find out how to find out the length of the major axis.<BR>\n" );
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document.write( "Draw an ellipse with major axis = 2a<BR>\n" );
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document.write( "Put in the center, the focus, and the object at perigee.<BR>\n" );
document.write( "If the focus is the sun:<BR>\n" );
document.write( "perihelion = distance from focus to object = p<BR>\n" );
document.write( "distance of focus from center = c<BR>\n" );
document.write( "Eccentricity = c/a<BR>\n" );
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document.write( "a = p + c<BR>\n" );
document.write( "a = p + ae<BR>\n" );
document.write( "a-ae = p<BR>\n" );
document.write( "a(1-e) = p<BR>\n" );
document.write( "a = p/(1-e)<BR>\n" );
document.write( "2a = 2p/(1-e)<BR>\n" );
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document.write( "You are given p and e so you can determine major axis = 2a<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
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