Daily Kennebec journal. [microfilm reel] (Augusta, Me.) 1870-1975, 1911-03-02
SUN Is BAD TiMEkEEPER.
United States Naval Observatory
Bases Its Calculations on stars IN
stead of Trusting Old Sol.

If large number of persons were
asked the question what is meaii'
when in daytime clock says II
clock" about 80 out Of every 100 Wouiu
answer that at that hour the sun Is
on the meridian and it is noon bu'
the sun is not on the meridian eaelI
dav VIXEN the clock is at T..
Nearly every one has friend VINO
owns a valuable watch that keeps ex-
cellent time, and many time TINS
friend. on being asked the exact time.
has looked at his watch with great
deal of pride and has told the hour'
at the same time remarklng ms
watch regulates the sun. IL Ills
watch keeps as poor time as does tht
sun il should be sent to a matchmaker,
for the sun is IL Wretchcdiy bad time =
kceper. 1t sometimes Is as much as
a quarter of an hour fast, and at an
other season it may be an equal
amount SLOW. In fact. II may be said
that clock Of extreme precision. suen
as the astronomers use. is never eN-
actIv at II when the sun is on the
meridian.
But" il will be asked. "if the sun
does not give US our time. what, then'
does" AS every one knows, the ro-
tatjon of the earth on its axis is our
measure of time. each complete revo-
luton making a day. AS the earth ro-
.ates il carries our meridian around
with IT, and as the meridian crosses
through the heavenly bodies in sue
cession they are said to transit"
The interval Of time between two sue
tt ar flNf. oil Yet q
body across the meridian is called a
day.
II the body considered is star. we
have what is known to the astrono-
mer as a star day. or sideral day. The
stars are fixed. the earth rotates uni
formly on its axis, and as result the
sideral days for all stars are of equal
length But which star shall be
chosen as the most important In the
heavens, 50 that time shall be reck-
oned from it?
Instead of selecting a star the as
tronomers have picked upon the YER
nal equinox. the intersection in the
sky of the equator and ecliptic. When
| ii is on the meridian the astronomer S
clock says Oh. ON. 0s.. the beginning
of the sidereal day. whose hours run
| from Oh. to oath. In a great observa-
| tory the positions of the stars are re-
| corded in time kept by such side
real clock, and sidereal time is OF
great Importance to the astronomer.
Due to the annual revolution of the
earth about the sun the sun appears
| to move continuously eastward among
the stars. completing a journey once
| in a year The sun moves in what Il
called the "ecliptic." and its motion
| is from west to east among the stars
| This apparent annual motion or the
sun has very important consequences
Let US consider those only that refer
| to time.
Imagine a sun and star on the
| meridian together at noon on a Ger
| tain day. One complete revolution o.
the earth on it's axis would bring the
eartls meridian back to the star, ant
a sidereal day would have elapsed
In this interval of time the sun ha:
apparently moved eastward among
the stars. and it Is necessary for th'
earth to rotate little further on 1T
4 xxiss to overtake the sun, bring it ou
on the meridian and complete the sol