Evening star. [volume] (Washington, D.C.) 1854-1972, 1902-05-03
THE HEAVENS IN MAY
Stars Of First Magnitude
Above the Horizon.
THE LEGEND OF ORION
A STUDY OF THE SPECTRUM OF
ARCTURUS.
Stellar Magnitude of the Sun-Planets
That Are Visible This
Month.
Written TO: The Evening Star.

Written TO: The Evening Star.
Eight stars of the first magnitude will
| be above the horizon at o'clock this even
! ing or between I and o'clock near the
| close of the month. Low in the west may
| be seen Procyon, the Little Dog tCanis
| MINOR, the last of Orion's splendid train
| to disappear below the horizon. At about
| the same altitude in the northwest will
| be found Capella, the Goat the principal
star in Auriga. the Wagner. Midway be-
| tween these two bright stars and at a
| somewhat greater distance above the hori-
the Twins (GeminD, Castor and
| Pollok. the former of which-the more
northeriy-is a bright second magnitude
star. while the latter being somewhat
| brighter, stands in the list of the first mag
nitudes.
| In the northeast Vega, or Alpha Lyrae
which is to be one of the. briliants of the
| northern evening sky all through the sum-
mer months, taking the place which Ca
| pella has occupied throughout the winter
| is now fairly above the horizon at o clock.
| Vega is the principal star in the Tyre of
! Orpheus. 1t is the rival in splender of
| both Capella and Arcturus which latter
star may now be seen in mdheavens lit
| tie south of east. The relative magnitudes
| of these three stars is a matter difficult to
| decide, on account of their difference in
| color. Arcturus is yellow star. inclined
| color, while Vega is bluish-white.
In the southeast, at about one-third of
| the distance from horizon to zenith. stands
| Spica. the Wheat-ear, in the constellation
Virgo. Like Vega, Spica is a ''Sirian,"
| white star. and. though less brilliant than
| Vega, it is one of the most beautiful of the
| stellar host. At about three-hfths of the
| distance from this star to Procyon is Regu-
| lus, the principal star in Leo and the jewel
| in the handle of the Sickle" which forms
| the Lions head and Shoulders. The eighth
lctnr of cl
! the hour of observation is Antares, in
| the Scorpion, which has but just thrust
| its lobster-like claws above THE horizon
| in the southeast.
The Legend of Orion.
| The position of the Scorpion. just rising
while Orion. whom we have been admiring
| all through the winter months. has but just
| disappeared in the west suggests an ex-
PLANTATION of the story anciently told of the
| way In which this mythical huntsman met
| his death. Proud of his exploits in the
chase. Orion, ii is said, boosted to Latona
and Diana that he could kill any animal
they might send against him. They sent a
| scorpion, which easily vanquished the over
| confident giant with its venomous sting.
| Whether this story was suggested by the
| relative positions of the two constella tons
| or not, the fact remains that no sooner does
| the Scorpion appear upon the celestial
| scene than Orion vanishes from it. Through
| out the summer months this slayer of
! Orion will take his place the most bril-
| liant constellation of the southern evening
! Skies
A Mighty Orb.
One of the most interesting of the celes-
! tial objects now visible is the brilliant star
Arcturus. 1t is a star of the 'solar" type.
| Its spectrum, according to Sir Norman
| Lockyer, Is practically Identical with that
| of the sun. This means that it is a body at
! the same stage of evolution as the sun-a
gaseous body enveloped in 'photosphere'
| of intensely luminous clouds, above which
! floats an atmosphere made up of gases and
| the vaporS of metals, to whose absorptfve
action are due the dark lines which cross
| the stars spectrum. AS was mentioned last
month, Arcturus has large proper mo-
ton" which would seem to indicate that
| it is relatively near star. This SUPPOSE
| ton, however, is not supported by the OBJ
| EIkin with the object Of ascertainfng its
| distance from us. AS a result of DIR. Elkin's
| careful measures. made with the heliometer
| Of the Yale observatory, astronomers have
been driven to conclude that this brilliant
| orb cannot be at less than eight or ten
! times the distance of Srius-about nine
flight years'-and is probably at even
greater distance than this. In that case, to
| shine as brilliantly as it does. its bulk must
be fully that of thousand suns; six thou
/ sand suns Is the estimate-rather wild, per-
| haps-which to some astronomers appears
| to be more probable. At any rate, there
can scarcely be a question that this celes-
] tial orb is vastly larger than the sun. which,
| removed to its distance. would probably
! become invisible to the naked eye
| Some three or four years ago Prof E. F.
| Nichols of Dartmouth College undertook
series Of observations with an exceedingly
delicate thermometrtcal instrument which
| he calls "radiomicrometer," for the pur-
pose of determining the amount of heat
| received by us from the planets and the
| brighter Of the fixed stars. Arcturus was
| one of the stars investigated. Although the
| results were not quite conclusive they
seemed to Indicate that the heat received
from this star Is about the same as would
be received from a paraffin candle at the
distance of six miles.
The Sun as Star
Prof. Newcomb in his recently published
| book the stars. has done some rather
interesting figuring based the stellar
| magnitude of the sun, as determined indie
pendently by three eminent astronomers.
| taking as its most probable value the mean
| Of the three estimates. In the present sys-
| tenn OF reckoning star magnitudes the Tight
| ratio is fixed at 2.512. That is to say, an
/ average star of any given magnitude is
2512 times bright as average star of
| the magnitude next below. Thus, star Of
the first magnitude is trife more than
two and half times bright of
| the second magnitude; star two and
| half times as bright as that (about the
/ brightness Of Arcturus) would be OF magni-