The sun. [volume] (New York [N.Y.]) 1833-1916, 1899-09-12
TIE NORTH STAR rs THREE SUNS
No Eye mt the Telescope Can See Them,
But the Camera Proves 1t.

Tho news from Lick Observatory that the
North Star, 255. 900 000. 900 OF miles away from
us, has been found tobe not one star. but three
swinging around In great orbits like the moon
earth and SUMS another remarkable result
OF the application OF photo-spectroscopyt to the
telescope study OF the heavens. Always fas-
cinating, the search for double and multiple
stars has become o, the highest interest since
the spectroscope has made 1t possible to dis
cover multiple stars which the greatest tele-
scopes do not reveal to the eye. The three
components OF Polars cannot be seen with the
most powerful telescope in the world. But the
Lick star spectroscope. attached to the great
36-inch refrnctor. makes IL plain that there
are suns revolving about n sun who're the eye
distinguishes but one twinkling light.
Ten years ago at the Harvard University
Observatory the first photo pectroscoplo null
tiple star was discovered unex pectedly. The
star Mizar. the middle stnr OF the handle Of the
Big Dlpper. has been called ''nakcd-eyo"
double because 1t has a visible companion.
Alcor. close to 1t. But Ricco In 1850 discov-
cred with the telescope that Mizar had tele-
scopio double. Mizar seems to have beon the
first double star discovered with a telescope.
The apparent distance between MZar and
Alcor Is nearly forty times the distance that
separates the com ponents OF Mizar. The tele-
scope shows too that there are other stars be-
tween Mar and Alcor
Two centuries after the telescope revealed
two stars in Mizar the spectroscope showed
that the brighter Of the components was Itself
made up Of two stars. In photographs taken
at the Harvard Observatory in 1889 the X line
in the spectrum OF hizar appeared double.
| In other plates the line was single.
| In others 1t was hnzy. close scrutiny
| OF all the plates showed that the line
| was double at intervals OF flty-two days
| This proved to astronomers that the brighter
| com ponent OF Mizar was really two stars. A
| spectroscope takes cognizance OF the motion OF
| a star to or from the earth When one star
begins 70 approach and the other to recode
| from us. the lines in the spectrum OF the APP
| preaching star will be displaced toward
| the violet end. while those OF the
| receding star will be displaced toward the
red end. The lines will at first appear hazy.
but when the approach and recession OF the
stars reach a maximum tho lines will appear
double. The calculated distance between the
| components OF Mizar Is about 143000.0O0
miles. and the brilliancy OF the star is estimated
| to be over hundred times greater than that
| OF our sun.
A mum Der Of other photo spectroscopic m ulti-
pie stars have been discovered recently. With
the Lick telescope and speetroscope. fourteen
| have been found. This method OF discovery
came about from the use Of the spectra to
determine the velocity with which stars
approached or reccded from the earth. The
North Star. it was found a short while ago. Ia
now shooting earthward at velocity OF sixteen
miles second. Two OF the suns Of the North
Star triplet revo!ve about each other every
four days and these two swing about the
| third.