252 ASTRONOMYANDTHEBIBLE
binaries, these being cases where two stars—giant
suns really—revolvearoundtheircommoncenterof
gravity. Byhighandabstrusemathematicalprocesses,
fair determinations of theirdistance from theearth
canbemade.
"TheresultofanumberofmeasuresoftheOrionbi-
nariesisthattheirmeanparallaxisonetwo-hundredth
ofone secondofarc. Parallaxmeans,gotoa star,
lookbackthisway,andmeasuretheangular distance
of the earth from our sun. The linear distance is
93,000,000 miles,and theangular measurement from
these stars in Orion is one two-hundredth of one
second. Then two hundred lines, each 93,000,000
mileslong,endtoend,wouldfillout onesecond of
arc,or18,600,000,000miles. Therearesixtyseconds
inoneminute,or1,116,000,000,000miles,which,mul-
tipliedbyfifteen (theopeninginOrionbeingfifteen
minutes of an arc wide), equals 16,740,000,000,000
miles. Andthisistheenormouswidthofthecolossal
openingleadinginto thecavern.
'Thenninetythousandlittleringsofthedimensions
ofthe earth's orbit, each with a sun in the center,
could enterthis abyss sidebyside and beengulfed.
Andallthesedimensionsarelessthanthereality,with-
outdoubt.
"The distanceof therear ofthe chasm fromthe
openingcannotbe measured;butitmustbe atleast
threetimes greaterin depththanwidth, orfifty-one
trillion miles. But this is also the distance of the
giantsun Siriusfromtheearth. ItandAlphaCen-
tauri following would find ample room within this