Astronomy and the Bible;

DIFFERENCEINGLORY^187

starhasacompanionwhichemitsaboutone sixthas
muchHght as itself. Accordingtothe mostcareful
estimateofthebrilliancyofAlphaCentauri,thelight
we receive from itis about igqso'oooooo^^^^^^which
we receive from thesun. But if the sun were re-
movedtoadistanceequaltothatofAlphaCentauri,
itwouldshinewithonly52,900,000,000 P^^^of itspres-
entbrilliancy. Itfollows,therefore,thatthestaremits
aboutthree timesas muchlightasthe sun. Aman
situatedatAlphaCentauriwouldseethesunasastar
onethirdasbright asAlphaCentauriappearstous.
Hereisadifferencewhichcannotbeaccountedforby
adifferenceofdistance.
Take for another example the light of the star
Sirius. Becauseoursun ismuchnearerthanSirius,
itismuchbrighter. Siriusisconsideredtobehalfa
milliontimesfartherawaythanthesun. Iftheearth
were midway between the places these two bodies
nowoccupy, thesun would giveus onetwelfththe
lightnowgivenbySirius,andSiriuswouldshinefour
timesbrighter. Sincefourtimestwelveisforty-eight,
itfollowsthatSiriusis forty-eighttimesbrighterin-
trinsicallythanthesun.
Bysimilarreasoning,itisjudgedthatifAlphaCen-
tauriwereremovedtothedistanceatwhich 61 Cygni
liesfromus,althoughtherebyitslightwouldbedimin-
ishedtooneninthofitspresentvalue,itwouldnever-
theless outshine eithercomponent ofthe double star
61 Cygnimorethaneleventimes.
Intheseinstances,distanceswouldnotaccountfor
thedifferenceinbrightness. Thereappearstobean