What does the dreaded "E" word mean, anyway.
http://www.accessmylibrary.com/article/print/1G1-59210814
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E$%%)E$&$BPP":'/6$E"#)+:"&'%$&):?'"G):'#+'*#"#):?'#9"#'D:?&)*9'@)&&'*#)&&'0/'#"$?9#'0$#'#9"#'?%"BB"%'B",'9/:E/>+%#9'0/
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1 of 9
11/17/10 9:07 AM
What does the dreaded "E" word mean, anyway.
http://www.accessmylibrary.com/article/print/1G1-59210814
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?%"6$"&'/=+&$#)+:'@/%/')B8%+=/6'):#+'#9+*/'):9"0)#):?'#9/'&":6CX
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>+%B'X/=+&=/6X'E&/"%&,'):'#9/'=/%:"E$&"%'*/:*/'":6'):'":'/*8/E)"&&,'E%$E)"&'*8+#a'#9/'=/%,'&"*#'@+%6'+>'#9/'0++Gb'^+*#
*#$6/:#*'9"=/'>")&/6'#+'"88%/E)"#/'#9/'):E)*)=/'":6'):#/:6/6'X?+#E9"X'+>'#9/*/'E&+*):?'&):/*3'@9)E9'9"=/'?/:/%"&&,
0//:'%/"6'"*'"'8+/#)E'%/=/%)/3'"'9"%B&/**'&):?$)*#)E'>&+$%)*9'/**/:#)"&&,'6/=+)6'+>'E+:#/:#3'9+@/=/%'%)E9'):')B"?/%,C'I:
>"E#3'#9/'E"::,'R"%@):'$*/6'#9)*'B"N)B"&&,'/>>/E#)=/'&+E"#)+:'#+'B"G/'"'#/&&):?'8+):#'"0+$#'#9/'"0*+&$#/'?&+%,'":6
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Q/'$*$"&&,'%/?"%6'8&":/#"%,'89,*)E*'"*'#9/'8"%"?+:'+>'%)?+%+$*'*E)/:E/3'@9)&/'6)*B)**):?':"#$%"&'9)*#+%,'"*'"
&)?9#@/)?9#'/N/%E)*/'):'6$&&3'6/*E%)8#)=/'E"#"&+?):?'#9"#'":,'8/%*+:'@)#9'*$>>)E)/:#'8"#)/:E/'B)?9#'"EE+B8&)*9C'M$#
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#+':+@9/%/3'):'*9"%8'E+:#%"*#'@)#9'&)>/O*'9)*#+%,3'6/8)E#/6'"*'"'6,:"B)E'":6'$8@"%6&,'?%+@):?'#%//C'S9/'D"%#9
%/=+&=/*'):'$:):#/%/*#):?'*"B/:/**3'0$#'&)>/'/=+&=/*'0,'$:>+&6):?')#*'8+#/:#)"&'>+%'/=/%'/N8":6):?'6)=/%*)#,'"&+:?
"6B)##/6&,'$:8%/6)E#"0&/3'0$#'@+:6/%>$&&,'="%)+$*3'0%":E9):?*a
Whilst this planet has gone cycling on according to the fixed law of
gravity, from so simple a beginning endless forms most beautiful and most
wonderful have been, and are being, evolved.
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#9/'=/%:"E$&"%'B/":):?'#9/:'E+:=/,/6'0,'#9/'@+%6C'.+%'#9/'B/E9":)*B'+>':"#$%"&'*/&/E#)+:',)/&6*'+:&,'):E%/"*):?
"6"8#"#)+:'#+'E9":?):?'&+E"&'/:=)%+:B/:#*3':+#'8%/6)E#"0&/'8%+?%/**'):'#9/'$*$"&'*/:*/'+>'E+*B)E'+%'?/:/%"&
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9+*#3'B",'0/'T$*#'"*'@/&&'"6"8#/6'#+')#*'*$%%+$:6):?*3'":6'T$*#'"*'@/&&'/:6+@/6'@)#9'8%+*8/E#*'>+%'/=+&$#)+:"%,
8/%*)*#/:E/3'"*')*'#9/'B+*#'):#%)E"#/'E%/"#$%/3'/N[$)*)#/&,'"6"8#/6'):'"&&'8"%#*'#+'"'E+B8&/N'":6'6":?/%+$*'/N#/%:"&
/:=)%+:B/:#C'^+%/+=/%3'*):E/':"#$%"&'*/&/E#)+:'E":'"6"8#'+%?":)*B*'+:&,'#+'&+E"&'E)%E$B*#":E/*3'":6'*):E/'&+E"&
E)%E$B*#":E/*'E9":?/'):'":'/>>/E#)=/&,'%":6+B'B"::/%'#9%+$?9'?/+&+?)E"&'#)B/3'#9/'8"#9@",*'+>'"6"8#)=/'/=+&$#)+:
E"::+#'0/'8%/6)E#/6C
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%/?$&"#/6'0,':"#$%"&'*/&/E#)+:'E+$&6'*E"%E/&,'9"=/'*$??/*#/63'#+'R"%@):3'#9/'&"0/&'X/=+&$#)+:3X'":'+%6):"%,'D:?&)*9
@+%6'>+%'*/[$/:E/*'+>'8%/6)E#"0&/'":6'6)%/E#)+:"&'$:>+&6):?C'Q/'B$*#'#9/:3'":6'+0=)+$*&,3'"*G'9+@'X/=+&$#)+:X
"E9)/=/6')#*'E+$8'):'0/E+B):?'#9/':"B/'>+%'R"%@):O*'8%+E/**PP"'#"G/+=/%'*+'E+B8&/#/'#9"#'#9/'@+%6'9"*':+@'"&B+*#
V0$#':+#'[$)#/3'"*'@/'*9"&&'*++:'*//W'&+*#')#*'+%)?):"&'D:?&)*9'B/":):?'+>'X$:>+&6):?X'":6'9"*'#%":*B$#/6'V+%'*9+$&6
@/'*",'X/=+&=/6XcW'):#+'":'/>>/E#)=/'*,:+:,B'>+%'0)+&+?)E"&'E9":?/'#9%+$?9'#)B/C
S9)*'):#/%/*#):?'*9)>#3'6/*8)#/'R"%@):O*'+@:'%/#)E/:E/3'+EE$%%/6'8%)B"%)&,'0/E"$*/'"'?%/"#'B"T+%)#,'+>'9)*
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#9/'E+B>+%#):?'":6'#%"6)#)+:"&'=)/@'#9"#'9$B":'E+:*E)+$*:/**'B$*#'%/8%/*/:#'"'8%/6)E#"0&/'V)>':+#'"'6)=):/&,
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2 of 9
11/17/10 9:07 AM
What does the dreaded "E" word mean, anyway.
http://www.accessmylibrary.com/article/print/1G1-59210814
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9)*#+%,3'#+'/B89"*)d/'#9/'?/:/"&+?)E"&'X6/*E/:#X'+>'+$%'*8/E)/*3':+#'+$%'X"*E/:#X'#+'9)?9/%'&/=/&*'+>'E+:*E)+$*:/**CW
Q9/:'I'@"*'"',+$:?'0+,3'?%+@):?'$8'+:'#9/'*#%//#*'+>'!/@'F+%G'H)#,3'#9/'<B/%)E":'^$*/$B'+>'!"#$%"&'()*#+%,
0/E"B/'B,'*/E+:6'9+B/'":6'):*8)%"#)+:C'I'&+=/6'#@+'/N9)0)#*'B+*#'+>'"&&PP#9/'S,%"::+*"$%$*'*G/&/#+:'+:'#9/'>+$%#9
>&++%'":6'#9/'*#"%'*9+@'"#'#9/'"6T"E/:#'(",6/:'A&":/#"%)$BC'I'T$??&/6'#9/*/'#@+'8"**)+:*'>+%'B":,',/"%*'":6
/=/:#$"&&,'0/E"B/'"'8"&/+:#+&+?)*#f'H"%&'7"?":3'B,':/"%PE+:#/B8+%"%,'>%+B'#9/':/)?90+%):?':/=/%&":6'+>'M%++G&,:
VI'?%/@'$8'):'g$//:*W'@/)?9/6'#9/'*"B/'#@+'):#/%/*#*'):'#9/'*"B/'0$)&6):?'0$#'+8#/6'>+%'"*#%+:+B,'"*'"'E"&&):?C'VI
9"=/'"&@",*'*$*8/E#/6'"'0"*)E'0)+&+?)E"&'6/#/%B):)*B'0/9):6'+$%'+88+*)#/'E9+)E/*C'H"%&'@"*'#"&&'":6'&++G/6'$8
#+@"%6'#9/'9/"=/:*f'I'"B'*9+%#/%'#9":'"=/%"?/'":6'#/:6'#+'&++G'6+@:'"#'#9/'?%+$:6CW
^,'/**",*'B",'0/'G:+@:'>+%'#9/)%'#"E#)E'+>'*/&/E#):?'+66'&)##&/'#)60)#*'"*')&&$*#%"#)+:*'+>'?/:/%"&'#9/B/*C'M$#'@9,3'#+
B"%G'#9/'%/+8/:):?'+>'#9/'(",6/:'A&":/#"%)$B3'@+$&6'I'9)?9&)?9#'*$E9'"'[$)%G,'":6'"88"%/:#&,')%%/&/=":#'*$0T/E#'"*
#9/'+6,**/,'+>'#9/'#/%B'X/=+&$#)+:X'):'*E)/:#)>)E3'":6'8%)B"%)&,'0)+&+?)E"&3'$*/PPP#9$*'*//B):?3'+:E/'"?"):3'#+'%/T/E#'#9/
E+*B+*'):'>"=+%'+>'#9/'6):+*"$%*c'^/#9+6'6+/*'):9/%/'):'B,'"88"%/:#'B"6:/**'V@9/#9/%'+%':+#'I'*$EE//6'):
E+:=/,):?'#9)*'%/"*+:):?'#+'B,'%/"6/%*WC'I'"B'@%)#):?'"0+$#'#9/'#/%B'X/=+&$#)+:X'):'#9/'6+B"):'I'G:+@'):'+%6/%'#+
/N8&)E"#/')#*'*#%)G):?&,'6)>>/%/:#'B/":):?'):'#9/'8%+>/**)+:'#9"#'I'8$#'"*)6/'0$#'*#)&&'&+=/'"=+E"#)+:"&&,C'<'6)*E$**)+:'+>
#9/'E+:#%"*#*'0/#@//:'0)+&+?)E"&'/=+&$#)+:'":6'E+*B+&+?)E"&'/=+&$#)+:'B)?9#'+>>/%'*+B/'$#)&)#,'"*'"'E+BB/:#"%,
"0+$#'"&#/%:"#)=/'@+%&6=)/@*'":6'"*'"'%/B):6/%'#9"#'B":,'*$88+*/6'6/0"#/*'):'*E)/:E/'"%)*/'>%+B'E+:>$*)+:
/:?/:6/%/6'0,'6)>>/%):?'$*/*'+>'@+%6*'":6':+#'>%+B'6//8'E+:E/8#$"&'B$66&/*'"0+$#'#9/':"#$%/'+>'#9):?*C
I:#/%6)*E)8&):"%,'$:)>)E"#)+:'%/8%/*/:#*'"'?%":6'":6'@+%#9,'?+"&'+>'):#/&&/E#$"&'&)>/3'0$#'?%/"#/%'$:6/%*#":6):?'E":
+>#/:'0/'@+:'0,'8%):E)8&/6'*/8"%"#)+:'":6'B$#$"&'%/*8/E#3'0"*/6'+:'E&/"%'6/>):)#)+:*'":6'6)*#):E#)+:*'"B+:?'#%$&,
6)*8"%"#/'8%+E/**/*3'%"#9/%'#9":'0,'>"&*/'$:)+:*'>+%?/6'@)#9'*$8/%>)E)"&'*)B)&"%)#)/*'":6'8"8/%/6'+=/%'0,'"'E+BB+:
#/%B):+&+?,'I:'+$%'$:6/%*#":6"0&/'6/*)%/'#+'$:)>,'#9/'*E)/:E/*'+>'#/B8+%"&'E9":?/3'@/'9"=/'#++'+>#/:'>+&&+@/6'#9/
A%+E%$*#/":'*#%"#/?,'+>'/:>+%E):?'"'E+BB+:'*/#'+>'E"$*/*'":6'/N8&":"#)+:*'$8+:'#9/'9)*#+%,'+%'"'*8/E)/*'":6'#9/
&)>/'+%'"'*#"%PP8"%#&,3'"#'&/"*#3'>+%'#9/'=/%,'0"6'%/"*+:'#9"#'0+#9'8%+>/**)+:*'$*/'#9/'#/%B'X/=+&$#)+:X'#+'6/:+#/'E9":?/
#9%+$?9'#)B/C'I:'#9)*'E"*/3'#9/'>$:6"B/:#"&'6)>>/%/:E/*'#%$B8'#9/'*$8/%>)E)"&'*)B)&"%)#)/*P":6'#%$/'$:)#,'@)&&'0/
"E9)/=/6'+:&,'@9/:'@/'"EG:+@&/6?/'#9/'6)*8"%"#/'*$0*#%"#/*'#9"#3'#"G/:'#+?/#9/%3'8%+0/'#9/'%":?/'+>'8+**)0)&)#)/*
>+%'#9/+%)/*'+>'9)*#+%)E"&'+%6/%C
S9/'R"%@):)":'8%):E)8&/'+>':"#$%"&'*/&/E#)+:',)/&6*'#/B8+%"&'E9":?/PP/=+&$#)+:'):'#9/'0)+&+?)E"&'6/>):)#)+:PP0,'#9/
#@+>+&6'8%+E/**'+>'8%+6$E):?'E+8)+$*'":6'$:6)%/E#/6'="%)"#)+:'@)#9):'"'8+8$&"#)+:'":6'#9/:'8"**):?'"&+:?'+:&,'"
0)"*/6'V*/&/E#/6W'8+%#)+:'+>'#9)*'="%)"#)+:'#+'#9/':/N#'?/:/%"#)+:C'I:'#9)*'B"::/%3'#9/'="%)"#)+:'@)#9):'"'8+8$&"#)+:'"#
":,'B+B/:#'E":'0/'E+:=/%#/6'):#+'6)>>/%/:E/*'):'B/":'="&$/*'V"=/%"?/'*)d/3'"=/%"?/'0%"):):/**W'"B+:?'*$EE/**)=/
8+8$&"#)+:*'#9%+$?9'#)B/C'.+%'#9)*'>$:6"B/:#"&'%/"*+:3'@/'E"&&'*$E9'#9/+%)/*'+>'E9":?/'="%)"#)+:"&'"*'+88+*/6'#+'#9/
B+%/'E+:=/:#)+:"&3'":6'B+%/'6)%/E#3'B+6/&*'+>'#%":*>+%B"#)+:"&'E9":?/')B8+*/6'0,':"#$%"&'&"@*'#9"#'B":6"#/'"
8"%#)E$&"%'#%"T/E#+%,'0"*/6'+:'):9/%/:#'V":6'#9/%/>+%/'8%/6)E#"0&/W'8%+8/%#)/*'+>'*$0*#":E/*'":6'/:=)%+:B/:#*C'V<'0"&&
%+&&):?'6+@:'":'):E&):/6'8&":/'6+/*':+#'%/"E9'#9/'0+##+B'0/E"$*/'*/&/E#)+:'9"*'>"=+%/6'#9/'6)>>/%/:#)"&'8%+8"?"#)+:
+>'B+=):?'=/%*$*'*#"0&/'/&/B/:#*'+>')#*'#+#"&)#,'0$#'0/E"$*/'?%"=)#,'6)E#"#/*'#9)*'%/*$&#'@9/:'%+$:6'0"&&*'%+&&'6+@:
*B++#9'8&":/*CW
3 of 9
11/17/10 9:07 AM
What does the dreaded "E" word mean, anyway.
http://www.accessmylibrary.com/article/print/1G1-59210814
S+')&&$*#%"#/'#9/'8/E$&)"%'8%+8/%#)/*'+>'="%)"#)+:"&'#9/+%)/*'&)G/'R"%@):O*'):'":'+0=)+$*&,'E"%)E"#$%/63'0$#':+#
):"EE$%"#/3'6/*E%)8#)+:a'7$88+*/'#9"#'"'8+8$&"#)+:'+>'/&/89":#*'):9"0)#*'7)0/%)"'6$%):?'"'@"%B'):#/%="&'0/>+%/'#9/
"6=":E/'+>'":')E/'*9//#C'S9/'/&/89":#*'="%,3'"#'%":6+B'":6'):'"&&'6)%/E#)+:*3'):'#9/)%'"B+$:#'+>'0+6,'9")%C'<*'#9/')E/
"6=":E/*'":6'&+E"&'E+:6)#)+:*'0/E+B/'E+&6/%3'/&/89":#*'@)#9'B+%/'9")%'@)&&'#/:6'#+'E+8/'0/##/%3'0,'#9/'*9//%'?++6
>+%#$:/'+>'#9/)%'*$8/%)+%'"6"8#"#)+:'#+'E9":?):?'E&)B"#/*PP":6'#9/,'@)&&'&/"=/'B+%/'*$%=)=):?'+>>*8%):?'+:'"=/%"?/C
VS9)*'6)>>/%/:#)"&'%/8%+6$E#)=/'*$EE/**'B$*#'0/'E+:E/)=/6'"*'0%+"6&,'*#"#)*#)E"&'":6':+#'?$"%":#//6'):'/=/%,'E"*/a'):
":,'?/:/%"#)+:3'#9/'9")%)/*#'/&/89":#'+>'"&&'B",'>"&&'):#+'"'E%/="**/'":6'6)/CW'M/E"$*/'+>>*8%):?'):9/%)#'#9/)%'8"%/:#*O
6/?%//'+>'9")%):/**3'#9/':/N#'?/:/%"#)+:'@)&&'E+:#"):'"'9)?9/%'8%+8+%#)+:'+>'B+%/'6/:*/&,'E&"6'/&/89":#*'V@9+'@)&&
E+:#):$/'#+'0/'>"=+%/6'0,':"#$%"&'*/&/E#)+:'"*'#9/'E&)B"#/'0/E+B/*'*#)&&'E+&6/%WC'S9)*'8%+E/**'+>'):E%/"*):?'"=/%"?/
9")%):/**'B",'E+:#):$/'>+%'B":,'?/:/%"#)+:*3'&/"6):?'#+'#9/'/=+&$#)+:'+>'@++&&,'B"BB+#9*C
S9)*'&)##&/'>"0&/'E":'9/&8'$*'$:6/%*#":6'9+@'8/E$&)"%'":6'9+@'E+:#%"%,'#+'"&&'#%"6)#)+:*'+>'Q/*#/%:'#9+$?9#'":6
/N8&":"#)+:'#9/'R"%@):)":'#9/+%,'+>'/=+&$#)+:3'":6'="%)"#)+:"&'#9/+%)/*'+>'9)*#+%)E"&'E9":?/'):'?/:/%"&3'B$*#'*+$:6'#+
#9/'E+BB+:'/"%C'<&&'#9/'+66'":6'>"*E):"#):?'8%+8/%#)/*'+>'R"%@):)":'/=+&$#)+:PP#9/'*/:*)0&/'":6'/N8&"):"0&/'0$#
[$)#/'$:8%/6)E#"0&/':"#$%/'+>'#9/'+$#E+B/'V6/8/:6/:#'$8+:'E+B8&/N'":6'E+:#):?/:#'E9":?/*'):'&+E"&'/:=)%+:B/:#*W3
#9/':+:8%+?%/**)=/'E9"%"E#/%'+>'#9/'"&#/%"#)+:'V"6"8#)=/'+:&,'#+'#9/*/'$:8%/6)E#"0&/'&+E"&'E)%E$B*#":E/*'":6':+#
):/=)#"0&,'0$)&6):?'"'X0/##/%X'/&/89":#'):'":,'E+*B)E'+%'?/:/%"&'*/:*/WPP>&+@'>%+B'#9/'="%)"#)+:"&'0"*)*'+>':"#$%"&
*/&/E#)+:C
S%":*>+%B"#)+:"&'#9/+%)/*'@+%G'):'"'B$E9'*)B8&/%'":6'B+%/'6)%/E#'B"::/%C'I>'I'@":#'#+'?+'>%+B'<'#+'M3'I'@)&&'9"=/'*+
B$E9'&/**'E+:E/8#$"&'V":6'"E#$"&W'#%+$0&/')>'I'E":'8+*#$&"#/'"'B/E9":)*B'#9"#'@)&&'T$*#'8$*9'B/'#9/%/'6)%/E#&,'#9":')>'I
B$*#'%/&,'$8+:'#9/'*/&/E#)+:'+>'X"'>/@'?++6'B/:X'>%+B'"'%":6+B'E&+$6'+>'="%)"#)+:'"0+$#'8+):#'<3'#9/:'E+:*#)#$#/'"
:/@'?/:/%"#)+:'"%+$:6'":'"=/%"?/'8+):#'+:/'*#/8'E&+*/%'#+'M3'#9/:'?/:/%"#/'"':/@'E&+$6'+>'%":6+B'="%)"#)+:'"0+$#
#9)*':/@'8+):#3'#9/:'*/&/E#'X"'>/@'?++6'B/:X'+:E/'"?"):'>%+B'#9)*':/@'"%%",PP":6'#9/:'%/8/"#'#9)*'8%+E/**'+=/%'":6
+=/%'$:#)&'I'>):"&&,'%/"E9'MC
Q9/:'+:/'"66*'#9/'+66)#,'+>'="%)"#)+:"&'#9/+%)/*'):'?/:/%"&'#+'+$%'*#%+:?'E$&#$%"&'":6'8*,E9+&+?)E"&'%/*)*#":E/
"?"):*#'#9/)%'"88&)E"#)+:'#+'+$%'+@:'/=+&$#)+:"%,'+%)?):'V"*'":'$:8%/6)E#"0&/'":6':+#':/E/**"%,'8%+?%/**)=/'&)##&/'#@)?
+:'&)>/O*'&$N$%)":#'#%//W3'#9/:'@/'E":'0/##/%'$:6/%*#":6'@9,'R"%@):O*'%/=+&$#)+:'*$%8"**/6'"&&'+#9/%'*E)/:#)>)E
6)*E+=/%)/*'):'%/>+%B"#+%,'8+@/%'":6'@9,'*+'B":,'8/+8&/'*#)&&'>")&'#+'$:6/%*#":63'":6'B",'/=/:'"E#)=/&,'%/*)*#3')#*
#%$&,'&)0/%"#):?'E+:#/:#C'VI'B$*#'&/"=/'#9/')**$/'+>'&)0/%"#)+:'>+%'":+#9/%'#)B/3'0$#'+:E/'@/'%/E+?:)d/'#9"#'#9/
*8/E)>)E"#)+:'+>'B+%"&*'":6'#9/'*/"%E9'>+%'"'B/":):?'#+'+$%'&)=/*'E"::+#'0/'"EE+B8&)*9/6'0,'*E)/:#)>)E'*#$6,'):'":,
E"*/3'#9/:'R"%@):O*'="%)"#)+:"&'B/E9":)*B'@)&&':+'&+:?/%'*//B'#9%/"#/:):?'":6'B",'/=/:'0/E+B/'&)0/%"#):?'):
#/"E9):?'$*'#+'&++G'@)#9):'+$%*/&=/*'>+%'":*@/%*'#+'#9/*/'[$/*#)+:*'":6'#+'"0":6+:'"'E9)B/%)E"&'*/"%E9'>+%'#9/
8$%8+*/'+>'+$%'&)=/*3'":6'>+%'#9/'*+$%E/'+>'+$%'/#9)E"&'="&$/*3'):'#9/'/N#/%:"&'@+%G):?*'+>':"#$%/CW
S9/*/'6)>>)E$&#)/*'):'?%"*8):?'R"%@):O*'?%/"#'):*)?9#'0/E"B/'/N"E/%0"#/6'@9/:'+$%'e)E#+%)":'>+%/0/"%*'B"6/'#9/)%
$:>+%#$:"#/'E9+)E/'+>'"'6/>):):?'@+%6PPX/=+&$#)+:XPP@)#9')#*'=/%:"E$&"%'B/":):?'+>'X6)%/E#/6'$:>+&6):?CX'Q/'@+$&6':+#
>"E/'#9)*'"66)#)+:"&'8%+0&/B'#+6",')>'X/=+&$#)+:X'9"6'$:6/%?+:/'"'E+B8&/#/'#%":*>+%B"#)+:'#+'0/E+B/'"'*#%)E#'":6
/NE&$*)=/'6/>):)#)+:'+>'0)+&+?)E"&'E9":?/PP@)#9'/"%&)/%'":6'/#,B+&+?)E"&&,'B+%/'"88%+8%)"#/'$*"?/*'#9/:'"0":6+:/6
":6'>+%?+##/:C'M$#')B8+%#":#'@+%6*'%"%/&,'$:6/%?+'*$E9'"'E&/":'*@)#E9'+>'B/":):?3'":6'X/=+&$#)+:X'*#)&&'B"):#"):*')#*
+%)?):"&'6/>):)#)+:'+>'X8%/6)E#"0&/'$:>+&6):?X'):'*/=/%"&':+:0)+&+?)E"&'6)*E)8&):/*P):E&$6):?'"*#%+:+B,C
Q9/:'"*#%+:+B/%*'#"&G'"0+$#'#9/'/=+&$#)+:'+>'"'*#"%3'#9/,'E&/"%&,'6+':+#'9"=/'"'="%)"#)+:"&'#9/+%,'&)G/'R"%@):O*'):
B):6C'7#"%*'6+':+#'E9":?/'#9%+$?9'#)B/'0/E"$*/'B"B"'":6'8"8"'*#"%*'?/:/%"#/'0%++6*'+>'="%,):?'6"$?9#/%'*#"%*3
>+&&+@/6'0,'#9/'6)>>/%/:#)"&'*$%=)="&'+>'6"$?9#/%*'0/*#'"6"8#/6'#+'#9/)%'8"%#)E$&"%'%/?)+:'+>'#9/'E+*B+*C'h"#9/%3
#9/+%)/*'+>'*#/&&"%'X/=+&$#)+:X'E+$&6':+#'0/'B+%/'%/&/:#&/**&,'#%":*>+%B"#)+:"&'):'8+*)#):?'"'6/>):)#/'":6'8%/6)E#"0&/
*/[$/:E/'+>'E9":?/*'$:>+&6):?'"*'*)B8&/'E+:*/[$/:E/*'+>'89,*)E"&'&"@*C'V!+'0)+&+?)E"&'8%+E/**'+8/%"#/*'):'/N"E#&,
#9/'*"B/'B"::/%3'0$#'#9/'&)>/'E,E&/'+>'":'+%?":)*B'E/%#"):&,'@+%G*'0/##/%'#9":'#9/'/=+&$#)+:'+>'"'*8/E)/*'"*'"'*+$%E/
+>'":"&+?,CW
I%+:)E"&&,3'"*#%+:+B,'$:6/:)"0&,'#%$B8*'0)+&+?,'):'>")#9>$&:/**'#+'#9/'/#,B+&+?,'":6'#9/'=/%:"E$&"%'6/>):)#)+:'+>
4 of 9
11/17/10 9:07 AM
What does the dreaded "E" word mean, anyway.
http://www.accessmylibrary.com/article/print/1G1-59210814
X/=+&$#)+:XPP/=/:'#9+$?9'#9/'#/%B':+@'9+&6*'>"%'@)6/%'E$%%/:E,'$:6/%'#9/'%"6)E"&&,'"&#/%/6'6/>):)#)+:'+>'#9/'0)+&+?)E"&
*E)/:E/*C'I:'>"E#3'"*#%+:+B/%*'9"=/'0//:'*+'#%$/'#+'#9/'+%)?):"&'6/>):)#)+:'#9"#'#9/,'E+:>):/'X/=+&$#)+:X'#+'9)*#+%)E"&
*/[$/:E/*'+>'8%/6)E#"0&/'$:>+&6):?'":6'%/*+&$#/&,'*9$:'#9/'@+%6'@9/:'6/*E%)0):?'E+*B)E'E9":?/*'/N9)0)#):?'#9/'G/,
>/"#$%/*'+>'0)+&+?)E"&'/=+&$#)+:PP$:8%/6)E#"0)&)#,'":6'&"EG'+>'):9/%/:#'6)%/E#)+:"&)#,C
<*'":')&&$*#%"#)+:'+>'#9)*'"*#%+:+B)E"&'$*"?/3'E+:*)6/%'#9/'B+*#'*#":6"%6'":6'E+:=/:#)+:"&'+>'"&&'*+$%E/*PP#9/
D:E,E&+8"/6)"'M%)#"::)E"'"%#)E&/'X7#"%*'":6'7#"%'H&$*#/%*X'V2K#9'/6)#)+:3'2JJ1'8%):#):?WC'S9/'*/E#)+:'/:#)#&/6'X7#"%
.+%B"#)+:'":6'D=+&$#)+:X'0/?):*'0,'":"&+?)d):?'*#/&&"%'X/=+&$#)+:X'#+'"'8%/8%+?%"BB/6'&)>/'E,E&/3'@)#9'#9/'6/?%//'+>
/=+&$#)+:'6/>):/6'"*'#9/'8+*)#)+:'"&+:?'#9/'8%/6)E#"0&/'#%"T/E#+%,a
Throughout the Milky Way Galaxy ... astronomers haw' discovered stars that
are well evolved or even approaching extinction, or both, as well as
occasional stars that must be very young or still in the process of
formation. Evolutionary effects on these stars are not negligible.
S9/'>$&&,'8%/6)E#"0&/'":6'&):/"%'*/[$/:E/'+>'*#"?/*'):'"'*#/&&"%'&)>/#)B/'V/=+&$#)+:3'#+'"*#%+:+B/%*W'%/E+%6*'#9/
E+:*/[$/:E/*'+>'"'6/>):):?'89,*)E"&'8%+E/**'):'#9/'E+:*#%$E#)+:'":6'9)*#+%,'+>'*#"%*a'#9/'E+:=/%*)+:'+>'B"**'#+
/:/%?,'0,':$E&/"%'%/"E#)+:*'6//8'@)#9):'*#"%*3'&/"6):?'#+'#9/'#%":*>+%B"#)+:'+>'9,6%+?/:'):#+'9/&)$BC
The spread of luminosities and colors of stars within the main sequence can
be understood as a consequence of evolution.... As the stars evolve, they
adjust to the increase in the helium-to-hydrogen ratio in their cores....
When the core fuel is exhausted, the internal structure of the star changes
rapidly; it quickly leaves the main sequence and moves towards the region
of giants and supergiants.
S9/'*"B/'0"*)E'*/[$/:E/'$:>+&6*'#9%+$?9'*#/&&"%'&)=/*3'0$#'#9/'%"#/'+>'E9":?/'V/=+&$#)+:3'#+'"*#%+:+B/%*W'="%)/*'"*'"
8%/6)E#"0&/'E+:*/[$/:E/'+>'6)>>/%/:E/*'):'B"**a
Like the rate of formation of a star, the subsequent rate of evolution on
the main sequence is proportional to the mass of the star; the greater the
mass, the more rapid the evolution.
^+%/'E+B8&/N'>"E#+%*'B",'6/#/%B):/'="%)"#)+:'):'*+B/'*#"?/*'+>'#9/'&)>/'E,E&/3'0$#'#9/'0"*)E'6)%/E#)+:"&)#,'V/=+&$#)+:3
#+'"*#%+:+B/%*W'6+/*':+#'"&#/%3'":6'8%/6)E#"0)&)#,'>%+B':"#$%"&'&"@'%/B"):*'8%/E)*/'":6'E+B8&/#/a
The great spread in luminosities and colors of giant, supergiant, and
subgiant stars is also understood to result from evolutionary events. When
a star leaves the main sequence, its future evolution is precisely
determined by its mass, rate of rotation (or angular momentum), chemical
composition, and whether or not it is a member of a close binary system.
I:'#9/'B+*#'%/=/"&):?'=/%0"&'E&$/'+>'"&&3'#9/'6)*E+$%*/'+>'#9)*'8"%#)E$&"%'*E)/:#)>)E'E$&#$%/'*//B*'#+'*9$:'#9/'@+%6
X/=+&$#)+:X'@9/:'9)*#+%)E"&'*/[$/:E/*'0/E+B/'#++'B/":6/%):?3'#++':+:6)%/E#)+:"&3'+%'#++'E+B8&/N'#+'/N8&"):'"*
*)B8&/'E+:*/[$/:E/*'+>'E+:#%+&&):?'&"@*PP/=/:'#9+$?9'#9/'/:6'%/*$&#'B",'0/'B"%G/6&,'6)>>/%/:#'>%+B'#9/'0/?)::):?
*#"#/3'#9$*')&&$*#%"#):?'*)?:)>)E":#'E9":?/'#9%+$?9'#)B/C'.+%'/N"B8&/3'#9/'*"B/'M%)#"::)E"'"%#)E&/'+:'*#/&&"%'/=+&$#)+:
:+#/*'#9"#'+:/'E":'+>#/:'%/"E9'E+:E&$*)+:*'"0+$#'#9/'+%)?):'+>'"'*#"%'+%'"'8&":/#'>%+B'#9/'%/&"#)=/'"0$:6":E/'+>
E9/B)E"&'/&/B/:#*'):')#*'8%/*/:#'E+B8+*)#)+:C
D"%#93'9+@/=/%3'9"*'0/E+B/'*+'B+6)>)/6'6$%):?')#*'?/+&+?)E"&'9)*#+%,'#9"#'@/'E"::+#'$*/'#9)*'):>/%/:#)"&'B/#9+6'#+
%/E+:*#%$E#'#9/'):)#)"&'*#"#/'+>'+$%'+@:'8&":/#C'M/E"$*/'#9/'E$%%/:#'E+:>)?$%"#)+:'+>'D"%#9O*'*$%>"E/'6/=/&+8/6'#9%+$?9
E+B8&/N'E+:#):?/:E)/*'":6'E+$&6':+#'9"=/'0//:'8%/6)E#/6'>%+B'*)B8&/'&"@*3'#9)*'*#,&/'+>'E9":?/'"88"%/:#&,'6+/*':+#
%":G'"*'/=+&$#)+:PP0$#'+:&,3'):'"*#%+:+B)E"&'8"%&":E/3'"*'0/):?'X">>/E#/6Xa
The relative abundances of the chemical elements provide significant clues
regarding their origin. The Earth's crust has been affected severely by
erosion, fractionation, and other geologic events, so that its present
5 of 9
11/17/10 9:07 AM
What does the dreaded "E" word mean, anyway.
http://www.accessmylibrary.com/article/print/1G1-59210814
varied composition offers few clues as to its early stages.
I'6+:O#'B/:#)+:'#9/*/'6)>>/%/:E/*'#+'&"B/:#3'#+'E+B8&"):3'+%'#+'E%)#)E)d/'"*#%+:+B/%*'):'":,'@",C'<>#/%'"&&3'#9/)%'$*/'+>
X/=+&$#)+:X'%/B"):*'B+%/'>")#9>$&'#+'/#,B+&+?,'":6'#9/'+%)?):"&'D:?&)*9'6/>):)#)+:3'@9/%/"*'+$%'R"%@):)":
%/E+:*#%$E#)+:'9"*'=)%#$"&&,'%/=/%*/6'#9/'+%)?):"&'B/":):?C'I:'#9)*'E"*/3'*):E/':/)#9/%'*)6/'@)&&'+%'*9+$&6'?)=/'$8')#*
$:6/%*#":6):?'+>'X/=+&$#)+:X'V"*#%+:+B/%*'0/E"$*/'#9/,'9"=/'%/#"):/6'":'+%)?):"&'":6'/#,B+&+?)E"&&,'E+%%/E#
B/":):?3'":6'/=+&$#)+:)*#*'0/E"$*/'#9/)%'%/6/>):)#)+:'/N8%/**/*'#9/'=/%,'9/"%#'+>'#9/)%'E/:#%"&'":6'%/=+&$#)+:"%,
E+:E/8#'+>'&)>/O*'9)*#+%,W3'+$%'0/*#'*+&$#)+:'&)/*'*)B8&,'):'/N8+*):?'#9/'&/?)#)B"#/'6)>>/%/:E/*'":6'/N8&"):):?'#9/'?++6
%/"*+:*'0/9):6'#9/'6)*8"%)#,'):'$*"?/C
I:'#9)*'@",3'"#'&/"*#3'@/'B",'"=+)6'E+:>$*)+:'":6'"&*+'#9/'*8/E)"&'>%$*#%"#)+:'?/:/%"#/6'@9/:'8%+&+:?/6'@%":?&/*
"%)*/'>%+B'B)*$:6/%*#":6):?*'+>'@+%6*'%"#9/%'#9":'>%+B'?/:$):/'6)*8$#/*'"0+$#'#9):?*'":6'E"$*/*'):':"#$%/C'Q/
/=+&$#)+:"%,'0)+&+?)*#*'B$*#'%/B"):'/*8/E)"&&,'*/:*)#)=/'#+'#9)*')**$/3'0/E"$*/'@/'*#)&&'>"E/'E+:*)6/%"0&/'+88+*)#)+:3
0"*/6'+:'E+:=/:#)+:"&'9+8/*'":6'>/"%*3'#+'+$%'):*)*#/:E/'#9"#'&)>/'/=+&=/*'):'$:8%/6)E#"0&/'6)%/E#)+:*3'@)#9':+
):9/%/:#'?+"&C'7):E/'"*#%+:+B)E"&'/=+&$#)+:'$89+&6*'0+#9'E+:#%"%,'8+*)#)+:*PP8%/6)E#"0)&)#,'":6'6)%/E#)+:"&)#,PP
/=+&$#)+:"%,'0)+&+?)*#*'://6'#+'/B89"*)d/'#9/)%'+@:'6)*#):E#)=/'B/":):?3'/*8/E)"&&,'*):E/'#9/'?/:/%"&'8$0&)E'>//&*
B$E9'B+%/'E+B>+%#"0&/'@)#9'#9/'"*#%+:+B)E"&'*/:*/'":6'@)&&'#9/%/>+%/')B8+*/'#9)*'B+%/'E+:?/:)"&'6/>):)#)+:'$8+:
#9/'9)*#+%,'+>'&)>/')>'@/'6+':+#'E&/"%&,'/N8&"):'#9/'&+?)E3'#9/'/=)6/:E/3'":6'#9/'*9//%'>"*E):"#)+:'+>'+$%'E9"&&/:?):?
E+:E&$*)+:C
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="%)"#)+:"&3'":6'R"%@):)":'X#"G/X'+:'/=+&$#)+:'@9)&/'"&*+3'":6'[$)#/'/N8&)E)#&,3'%/>$#):?'"'8%/=)+$*3'#%":*>+%B"#)+:"&
):#/%8%/#"#)+:PP%++#/6'):'+$%'E$&#$%"&&,'/*#"0&)*9/6'8%/T$6)E/*'>+%'#9/'B+%/'E+B>+%#):?3'"*#%+:+B)E"&'=)/@PP#9"#'9"6
0&+EG/6'+$%'$:6/%*#":6):?'":6'*G/@/6'+$%'#9+$?9#*'"0+$#'":')B8+%#":#'/8)*+6/'):'&)>/O*'9)*#+%,a
2C'e/%#/0%"#/*'X"&&'#9/'@",'6+@:CX'I:'+:/'+>'#9/'B+*#'E%$E)"&'":6'/:)?B"#)E'/8)*+6/*'):'#9/'9)*#+%,'+>'&)>/PP":6'"
E9"&&/:?/'#+'#9/'+&6/%3'B+%/'E+:?/:)"&')6/"'#9"#'&)>/'9"*'8%+?%/**/6'):'"'0"*)E"&&,'*#"#/&,3'&):/"%'B"::/%'#9%+$?9'#9/
"?/*PP:/"%&,'"&&'":)B"&'89,&"'B"6/'#9/)%'>)%*#'"88/"%":E/'):'#9/'>+**)&'%/E+%6'"#'/**/:#)"&&,'#9/'*"B/'#)B/3'":'):#/%="&
+>'*+B/'K'B)&&)+:',/"%*'V"0+$#'K4K'B)&&)+:'#+'KU1'B)&&)+:',/"%*'"?+W'E"&&/6'#9/'H"B0%)":'/N8&+*)+:C'V5/+&+?)E"&
>)%/E%"EG/%*'9"=/'&+:?'>$*/*'@9/:'B/"*$%/6'0,'#9/'):"88%+8%)"#/'*E"&/'+>'9$B":'#)B/CW'\:&,'+:/'B"T+%'89,&$B'@)#9
8%+B):/:#'":6'>+**)&)d"0&/'9"%6'8"%#*'6)6':+#'"88/"%'):'#9)*'):E)6/:#'+%'6$%):?'#9/'H"B0%)":'8/%)+6'"#'"&&PP#9/
M%,+d+"3'"'?%+$8'+>'E+&+:)"&'B"%):/'+%?":)*B*'$:G:+@:'#+'B+*#':+:*8/E)"&)*#*'#+6",'V"&#9+$?9'*#)&&'%/&"#)=/&,
E+BB+:'):'*9"&&+@'+E/":)E'@"#/%*W'0$#'8%+B):/:#'):'#9/'/"%&,'>+**)&'%/E+%6'+>'":)B"&'&)>/C
\:/'+#9/%'?%+$83'$:#)&'&"*#'B+:#93'"&*+'9"6':+'%/E+%6'@)#9):'#9/'H"B0%)":'/N8&+*)+:3'"&#9+$?9'&"#/'H"B0%)":
%/8%/*/:#"#)=/*'V@/&&'">#/%'#9/'/N8&+*)+:')#*/&>W'9"=/'0//:'G:+@:'>+%'*+B/'#)B/C'Q9/%/"*'8+8$&"%'#/N#*'9"=/'=)%#$"&&,
)?:+%/6'#9/'M%,+d+"3'#9/'"0*/:E/'+>'#9)*'+#9/%'?%+$8'9"*'0//:'8%+B):/:#&,'*9+@E"*/6'":6'8%+E&")B/6'9)?9&,
*)?:)>)E":#C'!+'=/%#/0%"#/*'9"6'/=/%'0//:'%/E+=/%/6'>%+B'6/8+*)#*'+>'#9/'H"B0%)":'/N8&+*)+:3'"&#9+$?9'E&+*/
%/&"#)=/*'@)#9):'+$%'89,&$B'V#9/'H9+%6"#"W3')>':+#'#/E9:)E"&&,'=/%#/0%"#/*3'9"6'0//:'E+&&/E#/6'V#9/'H9+%6"#"'):E&$6/*
#9%//'B"T+%'*$0?%+$8*a'#9/'#$:)E"#/*3'<B89)+N$*'":6')#*'%/&"#)=/*3'":6'#9/'=/%#/0%"#/*'8%+8/%WC
S9)*'"0*/:E/'+>'=/%#/0%"#/*'>%+B'*#%"#"'0/"%):?':/"%&,'"&&'+#9/%'>+**)&)d"0&/'":)B"&'89,&"'8%+=)6/6'"'*#%+:?'%",'+>
9+8/'>+%'8/+8&/'@9+'@)*9/6'#+'=)/@'+$%'+@:'?%+$8'"*'X9)?9/%X'+%'B+%/'/=+&=/6PP"'8%/6)E#"0&/'6)%/E#)+:C'I>'/=+&$#)+:
)B8&)/*'&):/"%'8%+?%/**)+:3'#9/:'&"#/%')*'0/##/%PP":6'$:)[$/&,'&"#/%'V+%'"&B+*#'$:)[$/&,3'?)=/:'#9+*/'8/*G,'0%,+d+":*W
E":'+:&,'/:9":E/'#9/'6)*#):E#)+:C'M$#'#9/'!+=/B0/%'_3'2JJJ3')**$/'+>'!"#$%/'):E&$6/*'"'8/%*$"*)=/'"%#)E&/'VX]+@/%
H"B0%)":'e/%#/0%"#/*'>%+B'7+$#9'H9):"3X'0,'RP5C'79$3'(P]C']$+3'7C'H+:@",'^+%%)*3'iP]C'j9":?3'7PiC'($3']C'H9/:3
;C'(":3'^C'j9$3'FC'])3'":6']PjC'H9/:W'%/8+%#):?'#9/'6)*E+=/%,'+>'#@+'=/%#/0%"#/'?/:/%"'@)#9):'#9/']+@/%'H"B0%)":
H9/:?T)":?'>+%B"#)+:'+>'*+$#9/%:'H9):"3'%)?9#'@)#9):'#9/'#/B8+%"&'9/"%#'+>'#9/'H"B0%)":'/N8&+*)+:C'VS9/'M$%?/**
79"&/'+>'@/*#/%:'H":"6"3'#9/'E/&/0%"#/6'*)#/'>+%'B+*#'8%/=)+$*'G:+@&/6?/'+>'/"%&,'H"B0%)":'":)B"&*3'8+*#6"#/*'#9/
"E#$"&'/N8&+*)+:'0,'*/=/%"&'B)&&)+:',/"%*C'S9/'%/E/:#&,'6)*E+=/%/6'H9/:?T)":?'>"$:"3'@)#9'/[$"&&,'/N[$)*)#/
8%/*/%="#)+:'+>'*+>#'":"#+B,3'9"*'0//:',)/&6):?'E+B8"%"0&/'+%'/=/:'?%/"#/%'#%/"*$%/*'>+%'B+%/'#9":'"'6/E"6/C'7//
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S9/*/'#@+'E%/"#$%/*PP/"E9'+:&,'":'):E9'+%'*+'):'&/:?#9'":6'&"EG):?'0+#9'T"@*'":6'"'0"EG0+:/'":6'):'>"E#'8+**/**):?
6 of 9
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What does the dreaded "E" word mean, anyway.
http://www.accessmylibrary.com/article/print/1G1-59210814
:+'0+:,'*G/&/#+:'"#'"&&PPB)?9#':+#'*#%)G/'"'E"*$"&'*#$6/:#'"*'@+%#9,'+>'):E&$*)+:'@)#9):'+$%'/N"&#/6'&):/"?/C'M$#'#9/*/
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8"%#*'#9"#'+%)?):"&&,'>+%#)>)/6'#9/'?)&&'+8/:):?*'":6'#9/:'B+=/6'>+%@"%6'#+'*$%%+$:6'#9/'B+$#9C'<&&'/"%&,'>)*9/*PP":6
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@9+'@%+#/'#9/'6/>):)#)=/3'B$&#)=+&$B/'#/N#'+:'):=/%#/0%"#/'":"#+B,'>+%'9/%'?/:/%"#)+:3'%/?"%6/6'#9/)%'*)B8&)E)#,'"*
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#9/*/'$&#)B"#/&,'*)B8&/'B$&#)E/&&$&"%'E%/"#$%/*'>%+B'"'=/%,'E+B8&/N'B/#"d+":C'.+%'/N"B8&/3'(+%"E/'QC'7#$:G"%63
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7 of 9
11/17/10 9:07 AM
What does the dreaded "E" word mean, anyway.
http://www.accessmylibrary.com/article/print/1G1-59210814
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+>'+%?":*'":6'>$:E#)+:*'$:)[$/'#+'^/#"d+"PP"&*+'/N)*#'):'6)E,/B)6*3'#9/:'#9/*/'E%/"#$%/*'"%/'8%+0"0&,'6/?/:/%"#/6
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+>'?%"=)#,fO'@9)&/'"6/[$"#/'>+%':+@3'E"::+#'9+&6'>+%'"&&'#)B/C'7#/&&"%'/=+&$#)+:'@)&&3'+:/'6",3'/:T+):'"'8%/6)E#"0&/'/:63
"#'&/"*#'#+'&)>/'+:'D"%#9C'g$+#):?'+:/'B+%/'#)B/'>%+B'M%)#"::)E"a
The Sun is destined to perish as a white dwarf. But before that happens, it
will evolve into a red giant, engulfing Mercury and Venus in the process.
At the same time, it will blow away the earth's atmosphere and boil its
oceans, making the planet uninhabitable.
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#+&/%"0&,'6)*#":#'>$#$%/3'#+'0/'*$%/3'0$#'E+:*)6/%'#9/')**$/'":+#9/%'@",3'):'E+B8"%)*+:'@)#9'#9/'=/%,'6)>>/%/:#'*#,&/'+>
E9":?/'G:+@:'"*'0)+&+?)E"&'/=+&$#)+:C'D"%#9'+%)?):"#/6'"0+$#'_CL'0)&&)+:',/"%*'"?+C'S9$*3'9"&>'+>'+$%'8&":/#O*'8+#/:#)"&
9)*#+%,'$:>+&6/6'0/>+%/'E+:#):?/:#'0)+&+?)E"&'/=+&$#)+:'8%+6$E/6'/=/:'"'*):?&/'*8/E)/*'@)#9'E+:*E)+$*:/**'*$>>)E)/:#
#+'B$*/'+=/%'*$E9'B"##/%*C'^+%/+=/%3'#9)*'*):?&/'&):/"?/'"%+*/'@)#9):'"'B"%?):"&'?%+$8'+>'B"BB"&*PP#9/'8%)B"#/*3
@9)E9'):E&$6/'"0+$#'411'+>'#9/'_3111'+%'*+'B"BB"&)":'*8/E)/*C'M,'E+:#%"*#3'#9/'@+%&6'9+&6*'"#'&/"*#'9"&>'"'B)&&)+:
*8/E)/*'+>'0//#&/*C'I>'"'B/":6/%):?'8%+E/**'E+:*$B/6'9"&>'+>'"&&'"=")&"0&/'#)B/'#+'0$)&6'*$E9'":'"6"8#"#)+:'/=/:
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8%+0"0)&)#)/*3'+>'9)*#+%,C
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):*8)%/'":,'8%"E#)E"&'E+:E/%:3'0$#'@/'9$B":*'6+'&)G/'#+'B$*/'":6'#+'@+:6/%C'S9/'E+:#):?/:E,'+>'+$%'/=+&$#)+:'+>>/%*
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"'?++6'6/"&'+>'&)>/'@)#9'$*'":6'8/%9"8*'&/"=):?'#9+*/'8%/=)+$*&,'):6/*#%$E#)0&/'0"E#/%)"'"*'#9/'9)?9/*#'B$#/
@)#:/**/*'#+'"'*#/&&"%'/N8":*)+:'#9"#'@)&&'>):"&&,'$:&/"*9'"'$:)E/&&$&"%'<%B"?/66+:C'\%'8/%9"8*'@/3'+%'+$%
*$EE/**+%*3'@)&&'9"=/'E+&+:)d/6'#9/'$:)=/%*/'0,'#9/:'":6'@)&&'*9/6'+:&,'"'0%)/>'#/"%'>+%'#9/'6/*#%$E#)+:'+>'"'&)##&/
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8 of 9
11/17/10 9:07 AM
What does the dreaded "E" word mean, anyway.
http://www.accessmylibrary.com/article/print/1G1-59210814
AC'h+*/'(+:+%"%,'H$%"#+%'):'I:=/%#/0%"#/*'"#'#9/'<B/%)E":'^$*/$B'+>'!"#$%"&'()*#+%,C
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l4121'5"&/3'"'8"%#'+>'H/:?"?/']/"%:):?C'<&&'%)?9#*'%/*/%=/6C'@@@C"EE/**B,&)0%"%,CE+B
S9/'<EE/**^,])0%"%,'"6=/%#)*):?':/#@+%G'):E&$6/*a'
9 of 9
11/17/10 9:07 AM