An introduction to astronomy: designed as a text-book for the use of students in college. By Denison Olmsted ...

J UPITel 48at.:197
of tlle olcs is indeed quite pc)rccptible by the telescope, anld
is ol)\ious to th eye in a correct drawing of the planet. (See
I:'rontispiece.) Such a figure might naturally be expected firom
the rapidity of his diurnal revolution, which is accolnplishllc
inl about 10 hours (9h. 551n. 21.s.3).*
A. place oni the cquator of Jupiter must revolve 450 miles
per minlute, or 27 times as fast as a place on the terrestrial
cquator. Th'.le distance of Jupiter ftom the sunl is 495,000,000
]ilcs (4195,81Y7,00).[ Illis plane of rotation is but slightlyt ilnclinel to the plane of Ilis orbit (only about 30), and consequeltly his climato expericnccs bu)t a slight change of seasons.
329.''The view of Jupiter thllouigh a good tclescope is one
of.tllhc ost mIlaglificent alnd interesting spectacles amlong the
hceavenly bodies..1The disk expands into a large and bright
orb like the full moon; tlhe spheroidal figure which theory assinlls to revolill.n worlds is herle pa)iblyr cxhibited to the c'e;
across the disk, arranged in parallel stripes, are discerned several dusky bandls, called belts; and four lrightl satellites, always
it att-cndancee but ever varyilng their )ositions) colmpose a:
splcn(did retinulll. IndlCed, astrononm10'rs gaze -with pecuiliar illterest on Jupiter and his moons, as affording a miniature representation of the whole solar system; repeating, oln a smaller
scale, thle saiame revolutions, and ecxmplifyting, iln a mannmer
more witliln the comlpass of our observation, tlhe same laws as
recgulate the entire assemblage of siun and planets.
330. The?Belts f J apriter, are variable in their number and
dimensions. AWith smaller telescopes only one or two are scem
across the equatorial regions; but with mIolr powerfull inlstlrulnments the nl1luber is increasecd, coNvering a great part o tllhe
disk. Occasionallay these belts retain nearly the same formt alnd
positiolIs for rmanly montlhs together, while at other times they
undergo great and sudden changes, and il One or two ilntances,
t.ey lhave been obscrved to break up and spread themselves
ov\er tle whole face of thle planet. The prevailing opinion
almongl astronomers in reference to ithe nature of these belts is,
tllhat they are piroduclcd by disturbances in tlhe plact's at.nos.
- Ahy.' Ilind.,