New-York tribune. [volume] (New York [N.Y.]) 1866-1924, 1896-08-09
A BIT OF CLOSE COMPILATION.
WHY THE ASTRONOMERS ARE ELArEu
BY THE RETURN OF BROOKss COMET.

BY THE RETURN OF BROOKSS COMET.
While NJ Javele looking intently into the
thirty-inch rejecting telescope OF the Nice OBJ
servatory the other night he observed faint,
fuzzy speck OF light which had not been visible In
that part of the heavens few evenings before In
significant the appearance OF this object
It's discovery produced no little sensation among
the astronomers OF the world. For It was promptly
identified as a comet first by Professor Brooks.
of Geneva, y. Y, in 1889 and expected TO return
this year But the calculation OF q comets period
and orbit is difficult task, and so many things
may arise to upset all predictions in regard to Its
behavior that the first return from distant space
CT one of these wanderers II 1t occurs en- schedule
time affords a signal triumph for the astronomical
mathematicians.
If you try compute the movements OF planet.
you have comparatively easy work. In the first
place. its orbit is pretty nearly circular You can
watch 1t all the way around the racetrack from
beginning to end. Then again. 1t IL a solid or
semi-sod mass whose weight remains substan-
TALLY unchanged. and which can be diverted but
little from its regular route by the attraction OF
other bodies Its pace moreover. is even less sub
ject change than its path. 1t Is different with
comet. II steals in from somewhere. no one seems
to know exactly where. but probably from regions
beyond the furthest planets Of the solar system.
rushes up toward the sun, describes swift cir
cult about that orb and then whisks away again
in either ar elliptica a parabolic path 1t gets
beyond observation soon that only section OK
its orbit be determined. and from this tho as
tronomers must estimate the rest
A great many of these curious little flying fog
banks never come back at all. A few return three
or four times having gone out as far as the orbit
of the planet Jupiter "a favorite destination for
outward bound short period" comets). and then
mysterousy disappear. People often hear Tor m
stance Of "Lexers lost comet" seen only In lT9;
Of De Nicos, whose last appearance was In 1874.
and OF Biela's. which split in two after making
several circuits, and then. subsequently to the re-
turn of the twin dust clouds in 1852 vanished COM
pletely. Enckes comet, which has come back reg
ularly thirty-three times since Its first observed
visit to the neghborhood of the sun. is without q
parallel In astronomical history 1t Will thus DO
seen that the fate of newly observed object OF
this class must be exceedingly problematcal There
have been no less than eight Of these reported
within the last six years Brooks's whose period
was estimated at a trihc over seven years was tho
first one due. The time when II should be midway
in its course around the sun, its "perihelion
passage" the astronomers call 1t. was put ~
october S 1t is too soon of course. to say how
exact this calculation will prove. But as the ap-
preaching comet appeared within small angle OF
the spot where ii expected 10 show itself, the
computation appears TO have been very accurate
Among the disturbing influences which act on
comets whose period is not more than hve, SIX or
seven years, the most conspicuous seems 10 De inc
attraction of Jupiter Indeed to this cause - oiten
attributed their original enlargement WITHIN TINS
planetary
that IT, when a comet Is close TO the ORBIT OF tne
giant planet Jupiter is himself In that part or MS
circuit he may throw II out OF It's course again
enough to prevent it's coming back TO the sun. 4
number of attempts have been made with the aid
of this hypothesis and elaborate computations, 10
identify some OF the comets with older ones
which have been lost. The suggestion has been
made for instance, that Brookss comet or 1897
1895 ia really IeXels; but while the general theory
meets with favor. this particular application OK u
has not been widely accepted.
Then again. comets waste their SUBSTANCE rap.
idly especially when near the sun. They throw ON
part of their matter, which trails behind theh iiho
smoke from Il rocket. and Is left D-hihd tor'
ever in space. on rare occasions, strange us
torton of the tail Is noted which suggests the pos
sbilitv of a collision with an asterold or swarm OF
me,eors And slight Irregularities In the time OF
while Encke's comet would return TWO noufs
and a half earlier than the computation called fors
and this acceeraton in speed was accounted ior
on the supposition that the comet encountered IN
,dsihie obstacles Scarcely the Tact or snort
entng OF the period established, however, oeIore
half of the gain IN time disappeared again lrininx
az are these quantities. compared with the periou
itself no attempt is made 10 explain them away ~
ina ,c,lracies SO clever writer as MISS Clerke as.
srirnes the genuineness OF the phenomenon. ana
discusses the possible causes OF II. These ana other
circumstances serve to show that comets, IKE
good many men, are not 10 be trusted when out OF
sight and will stand good deal or watcning' even
when at short range Brooks's comet. 10 DC sure
has thus far justified the confidence reposed In II ~
its scientific hackers, but 1t will undergo, ana de-
serve close scrutiny during this visit to the inner
circle OF planetary society.