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

PROlEIIs. 247
hibiting, inl a strilk)g light, thle numerical relations of tlhe
memllbers of the solar system. fIn the follotwing table the distan ces are taken fi'om I[erschel's Astronomny, and frolm these
thl otlher larticulars are dCetermined by thel precCeding rules.
It AMelrcury were taken as the standard of comparison, then the tl
rctardations of all the other plancts would be greater thall
unity; but, as it is convenicnt to take the earth as tlhe standard, the retardations of AMercury and Vecnus \ill be less than
unity; shlowing tihat tthe velocity (whicht is expressed by the
fraction inverted) is greater than thlat of the eartlh. In like
1mannllelr,'1 tlhe force of gravitation of an inferl'ior planet, bcing
greater than tlhat of the carth, is thle reciprocal of the tabular
iAUlJVi. SHIOWING-'lE N UMEliCAL RELATIONS OF THE'i PnRIMA.Y
Pllanets. i Retardations. I)tiinces. Per. Times. Rlecip. of'ravity.
Mercury...y 0.06221'1 0.38710 0.2408t 0.141985
rnus....... 085049 0,72333 0.61519 0.52321
Earth..... 1.00000 1,00000 1.00000 1.00000
Mars.. 1,2340 1,52369 1.88080 2.32170
Ju1)iter...... 2,28100 5.202 77 11.86700 2a7.06900
Saturl.... 3.08850 9.53878 29.6100 90.98900
Urtanus. 4.37970 19.18239 84.01200 367.95000
Nept.l.5.40040 30.14 5 12 16 5 1000 908.a2000
389. JROBLEM.8:?lon. 1.- -.Th..e oplanet?.a1llas Nwas discovered to have a perliod
of about.it. years. owlln much slower does it mnove in its orbit
thtan thle earltl.- -low mucht further is it frlom the sllun. ——...... and
how much less does it gravitate toward the sun? As.....
1.6Y, 1):. 2.79, 1L:::::.80.
]By alplying tlle proportional numbers determtined by this
p)roblem respectively to thl carth's motion per second, to its
(istance from the sult in miles, and to the slacc througll whichl
t.le carthl departs in a second( f'rom a tallgent to her orbit, we
may obtain the numcrical value of each of tlhese elemenhts.
JIPon. 2. —-- -.V.What would be the prtiod(ical time of a meteor or
planet revolving close to the oarth.