The times., 1899-04-03

IN THE ORION NEBULAE.
Curious Differences Existing Be
tween Different Parts.
Frnm the New NnrL TriLnncl

tffom the New ork Iflbune.)
An interesting discovery, reported by
Prof. ". W. Campbell OF the Lick Obser-
vatory, more than year ago has lust
received such confirmation that no excuse
remains for doubling Is genuneness any
longer. He found that if he examined cer-
ia:n parts o. the huge nebula in ;he con-
stellation of Orion with Il spectToscOpe one
of the Characteristic lines in tine spectrum -
a hydrogen line-was the most conspicuous.
But if he 80 adjusted the instrument as to
| inspect another region IN the same nehula
different hydrogen line exhibited 81.
| Lerior disiinctness.
When these observations were first pub
| lished they were received with some re-
serve in spite of Prof. Campbell's reputa-
tion for accuracy. Indeed, an eminent Ger
man authority, DR.. Scheiner, went SO far
as TO declare that the Californian was the
victim of a purely physiological delusion,
| and that the alleged phenomenon did not
| exist at all.
Since that time the Lick Observatory has
| come under the charge of a new director,
Prof James E Keeler, formerly OF the
| Allegheny Observatory-a spectroscopist of
| the first rank. a recent number of the
"Astronomische Nachrichten'' announces
| that DR.. Keeler has been looking at the
Orion neubla this winter and that he has
| verified Prof. Campbells observations.
And, although the fact has not been hith-
! erto published II may be added that two
other astronomers. whose regulations for
keen vision, practical experience, and lack
| of bias are well established, and whose
/ instrumental facilities are of the best, have
independently corroborated the original
story. II thus appears that Prof. Camp
! bell knew what he was talking about after
| all.
Although there have been two different
ia -f If
nebulae, some yielding "bright-line' spec
trum and others a continuous" spec
| trum no one has hitherto detected any
| such dissimilarity in one nebula as has
| been found by Prof. Campbell His
| achievement is one. therefore over which
both he and the Lick Observatory are to
| be congratulated.
The significance of il can be guessed III
part by anybody who has given a little at
tention 10 astronomy. II is believed that
| all the stars (which are really sunsj have
| at one stage in their history been enor-
mously extended and attenuated clouds Of
cool gas and dust That is what nebula
| is. But in the process of condensation
heat is developed, and ii has been custo-
mary TO credit the blush white stars with
| being the hottest, even hotter than the sun.
which is second type" star Lockyer
long ago proved by laboratory tests that a
| substances would often show slight differ
ences in its spectrum if the temperature
! was greatly changed. II may be Inferred
then, that the hydrogen gas in one part OF
the Orion nebula is much hotter than
masses OF the same element in other parts
| of the same object.
The remarkable eXpanse of the Orion
nebula, as viewed with the naked eye, and
| its enormous distance from the earth JUS
| tify one in regarding il as of almost in
| calcnlable size-not merely millions but
billions OF miles across. Hence II is easy
10 believe that the temperatures existing
in widely separated regions in that eeles-
tial fog bank may differ by hundreds, il
not thousands, of degrees.