The Minneapolis journal., 1901-03-23
SINCE TYCHO'S TIME
AndersOn's New Star the Most
Wonderful of Recent Years.
OBSERVATIONS AT GooDSELL
Unlike TychO's, However, Twill Not
he Long With Us-SOme
Theories.
Special to The Journal.

| Northneld, Mimi, March 23.-The as
tronomers at Goodsell observatory have
| been studying with great care the most
recent addition to astronomical knowl-
! edge-vfZ., Anderson's new star. Night
! ly observations and spectroscopic ex-
| aminations have been made for several
weeks when the weather would permit.
This star was discovered by DR.. Ander-
| son of Glasgow ON Feb. %, in the milky
| way, in the constellation of Perseus. The
right ascension was hours, "a minutes,
| 20 seconds its declination was plus 43 de-
grees, hours, minutes. Its magnitude
was 81; color, blush white.
There have been fifteen only of these
| temporary" stars discovered, including
the present one. The first was dis
covered in 1S4 B. c., by Hipparchus. A
| most remarkable temporary was dis
| covered by Tycho in 1872. Another re-
markable one was discovered by Kipler in
| 1904. These stars are called temporary
because they make a sudden appearance in
| the heavens and then gradually or abrupt
| ly disappear, usually growing less and less
| brilliant until the magnitude becomes too
small for a telescope to locate Most of
| the temporaries appear and fade away
| gradually, but the latest one shows varia-
tions OF exceptional interest. For ex-
| ample, on Feb %, it was at magnitude,
| on the oath it was Sd magnitude. Then it
| dropped gradually to IA on Feb. rs and
then it suddenly went down to I'd magni-
| tude. From March to March it in
creased slightly, then it suddenly dropped
| to less than Sd magnitude on March 6
and 7, increasing again. On March II
it had gone down to 4th magnitude, where
| it remained until March 21. On March 20
it was 4th magnitude, and on the 21st was
Az magnitude.
OF Brief Duration.
IL oI
servations that all the lines of the spec
trum are displaced to the right and left.
This seems to indicate great disturbance,
possibly in the chromosphere of the
| stranger. In his opinion the star will
| be Of short duration in visibility, but is
! the most wonderful since Tycho's time.
The ''G'' and "F"' lines Of the spectrum
are the brightest.
Professor Pickering reports that this
star must have been less than the 11th
| magnitude on Feb. 19, ass was shown by
his observations which would have dis
covered a star of that MAGNITUDE. He
also reports the star as being as bright
as Capella on Feb. %, which shows an in
crease of brightness of 10000 times in
four days. Thus it ranks as the brightest
star discovered since 1904.
Tycho's star was visible for. ~ years
and Kepler's was in sight for about an
equal length of time. The new star,
which was blush white at discovery,
changed to a reddish hue on Feb. q.
The spectrum of Anderson's star re-
sembles that of Nova Aurigal 1t con-
tains numerous dark lines. Several OF
these are associated with bright bands in
the less refrangible part. The bright
bands are of great width, amounting to
some30 tenthmeters, each accompanied
by dark lines in the refrangible side of
the spectrum BY comparing the spec
trum with that of Orionis the central
portion was found to be almost identical,
but the dark portion was displaced about
IS tenth meters toward the violet which
shows differential motion of some 700
miles a second. The movements OF the
new star are more rapid than those of
Nova Aurigal.
More Interesting Features.
Another interesting feature of the spec
trum is the presence Of fine dark lines
down the middle Of each bright line of
hydrogen and calcium. These are prob
ably reversals, and If they are they can
| be used to great advantage in finding the
| wave length of the substances showing
| other bright lines. II the new star is
| like Nova Aurigan it will end as neb-
ula, and if it does it will be good proof
of the fundamental metallic nature of
nebulae.
| A photograph taken with a 213-inch
| Darlot lens at Goodsell, covered all the
| region where the temporary was found,
| and showed all stars down to the eleventh
| magnitude, but there was not trace of
such star then (Sept. 26, 1900. A pho
tograph taken at Harvard on Feb. 49,,
| 1901 shows none above the eleventh mag
| nitude not already known The most re-
markable fact is that in the very regiou
| in the short space of three days new
| star should blaze out as the most brilliant
In that part of the heavens.
! Dr. Wilson has had an extended ex-
perience in astronomical photography, and
! has achieved some unusually good results.
| He took his first observation upon the new
| star at Goodsell observatory on Feb. 26.
He took spectroscopic photograph with
16-inch object glass and 60-degree
prism with no slit. A fast drift was in
dicated by the clock, equal to the length
of the lines of the spectrum. This
| evidenced the bands Of lines. Very broad
bright lines were shown, intense near re-
| frangible or violet end. They were accom-
panied in that end by bright dark lines,
except when the bright lines were
crowded together visually. The red end
was stronger than the blue. The G (Ha)
! was most vivid. Another strong, bright
| line was seen in the yellow.
| On Feb. q, a narrow slit was employed
| in the observation. This gave better
ueHnaLlOn OF Tue 1lHeS he DdAuS Sill
appeared broad. The lines were clearly
| triple. Two narrow dark lines appeared
superposed upon the bright lines.
| A comparison spectrum OF the moon
| showed the middle component of bright
lines to coincide substantially with the
solar dark lines. The spectrum Of the
star showed possibly small deviation to-
ward the red indicating, in al probability,
motion away from US at moderate We
locity.
The spectrum photographs of March g.
II, and Is show less width of bright hy-
drogen lines and bring out better the
dark absorption lines. Four strong brighi
bands in the green and yellow portions OF
the spectrum were shown in addition to
those on the other plates previously ex-
posed.
Variety of Theories.
There are a variety of theories as to the
cause of these temporary and variable
| stars. No simple explanation can be ex-
pected to be adequate for all types Of va
riables, for variable stars include those
which brighten up and fade out at longer
or shorter known periods of time and those
more like the one under discussion. which
are temporary. The spectroscopic phe-
nomena of temporary stars compare rather
| closely with the spectrum phenomena of
the suns chromosphere and prominences.
| accepted in regard to the sun, viz: Ex-
plosions.
LOckyer's Explanation.
The collision theory of Sir Norman Lock-
yer also explains many observable phe-
\ nomena. The probable diameters of the
| stars compared with their distances apart
| would seem to make such a theory non
plausible, but as this running together
could cause our temporary stars, and so