Delaware gazette and state journal. (Wilmington, Del.) 1883-1902, 1902-01-09
THU SKIES IN JANUARY.

month Of january Will ma as tolluWa;
Last QUARTER ON the 3lst, new on the
9th, first quarter on the 18th and full
on the 2}d She will be In arogee on
the 4th aud in rerigee on the 2lst, The
sun, after describing an arc of nearly
y degrees in course of the month, will
be within about l7la degrees south do.
oinat on ut the end In course Of the
year 1892, the second Of the new cen
TRY, five eel pses will occur three Of
the sun and two of The moon. be
earliest is partial clipse Of tho sun
ON the Sth of April, which. however.
will not be visible in our latitude. The
second will be 10 al eclipse of the
moon on April o2d, also Invisible hero.
The third will be partial solar eclipse
on May ith. again not visible in our
latitude and The 'ourth will he total
eclipse o. tho moon on October 18th,
which Will he Visible here 4 he last
one partial eclipse OF the sun, will
occur on October Both but will not be
visib @ fefe
Tho planet Mercury will be in flgit
tRrius during tho greater portion of the
mouth. but enter Aquarius toward tho
end Venus is IN Capricurnus, but will
suan enter aquarius, where she will
ranRin until the terminal on of The
month AT first sh0 will set little
alter 5 O'Clock in the evening, hut
toward tho end of the month about Z. 10
o clock She will be magnificent
oh cot in the souInweste portion Of
the sky agd will attain her greatest
brlllisroy on the Sth Of The month
Mars Is in Cspr cornuH, AMI az this
y anot sets rather early-a few m nutes
past Cit VIII not b. 10 Il favorable
position for observation The greRt
y anets Jupiter and Saturn o st il
very CLOSE together 10 the cons citation
Sagittarus, but as they set gu 10 carly
ii Will be difficult 10 get % good glimpse
OF thom Even the NEST brilliant stars
or planets at settling lose a coed deal Of
the luster they present in higher posi-.
ton Uranus is likewise in Sag tar us,
and Eeptuuo 10 Taurus, very c osa tn
tho boundary line that sepa. ates that
ons ellaton from Gemini
The planet Jupiter is remarkable not
a'one for Us gigantic size, but for It's
| partial ss!f-luminusity and its satellite
| sys en- 1t is certain that tho q ant
planet cam { receive all the heat it
displays from the sun, and no longer
need the dense clouds su rounding it
be mystery These clouds Tor long
tins somewhat rerpleSed the aStrono.
mers, who could not We y well account
| fot them on the superstition that
Jupiter received all his light from the
sun, as Mercury. Venus, Mars, the
GA tn, &c, Tbs clouds ne an indica
tion OF certain stage in the process Of
cooling, through which Jupiter, like
any other globe in our system has to
pass So the earth was oncs, before it
had cooled to such an extent that the
oceans passed ON the vaporous to the
fluid form in WHICH We now fld them
The satellite system OF Jupiter IS very
remarkable Tor more than one reason
In the first place The four satellites of
Jupiter wtre the fret bodies ever dis
covered that moved around another
| planet that is, as moons In nearly
all our textbooks on astronomy the most
intei esting history Of these four moons
of Jupiter is passed over either with
silence or with a breyity it CO tainlY
does not deserve. 1t is probably known
to most of our readers that we owe the
use Of magnifying lenses for astronomi
cal purposes principally, If not alto
gethee, to Galilei, TO whom 10 the
history of astronomy and science In
general very high place must be con
coded 1t was in the year 1910, in the
month of January that GHliiei for the
first time turned his telescope, designed
and manufactured by himself, on to
Jupiter ard noticed three faint stars
which caught his attention on account
Of their oloseness to the planet and
their arrangement nearly in straight
lineN with it He looked again next
night and noticed that they had changed
| lntf loo 10 fn hI1t
that the change did not seem to be such
as could result from Jupiter's owr
motion II the now bod los we fixed
stars Two nights later he was able tt
confirm this conclusion and tn infer
that the rev bodies were net tixec
sta $, but moving hdiea which accom-
panied Jupiter IN his movements A
fourth body was noticed on the 18th o.
January, and the motions Of all fou
we're soon recognized by Galiiei MS bsint
motions Of revolution round Jupiter al
centre With characteristic thorough
ness he watched the motions of the new
J bodies night after night. and by th,
date Of the publication of the hook IL
which he proclaimed bis important dis
; coYerY had areHdv estimated with yery
fair accuracy their periods Of revolu
; tiun round Jupiter. The new bodice
were at first called by their disouyere
Medloean auets, in honor OF his patroi
; Cosmo lie Medici, the Grand Duke o
Tuscany, but 1t was evident that he'd g
, revolving about planet. as the planet
themselves revolved about the sun
formed new class Of bodifs distinc
rom the known planets, and the nam
] OF satellite, suggested by Kepler a
applicable to the now bodies, as well q
to the moon, has been generally au
copied Now the d suuvery of nev
J oiass OF heavenly b1dies for neithe
$ the greatest astronomers OF antiquity
: Iipparchus and litulemy, nor o,ei
I CoperniGus and Tycho Brahe, knev
i anything OF the moonlihe character o
other bodies than our own moon wa
not alone remarkable per Sc, but it dis
= proved the correctness 1t the cd doc
trims that tho earth was the only ceutr
: : OF motion, and il tend d, moreover
t seriously to discredit the iniallibility o
! Aristotle and ptolemy, who had n'earl
t no knowledge Of the existence of euol
bodies
We cannot refrain from mention nj
another point in come ition with tn
moons OF Jupiter. The ques ion ha
often been and ia still 6ei ag asked VIII
we cannot see these remarkable object
with the naked eye Let very dis
3 tinguished and delightful writer, 81
Robert Ball, answer this question
"Wnat takes place in the eye OF til
astronomer who is observing tie y 'anet
90 the rstina an image ia formed 0
the great globe. The image is extremel
m mute; but owirg ctiielfy to tho dis
turhanoe OF our atmos mere the genuin
image is surrounded with region i
which the nerves OF the retna are NOR
or less affected by the light whic