Astronomy for Amateurs — John Stuart Mill — John Shaqi
Astronomy for Amateurs
John Stuart Mill · en
For the rest, among the beautiful and shining stars with which we made
acquaintance in the last chapter may be cited Sirius, which at a
distance of 92 trillion kilometers (57 trillion miles) from here still
dazzles us with its burning fires; Procyon or [alpha] of the Little Dog,
as remote as 112 trillion kilometers (69-1/2 trillion miles); Altaïr of
the Eagle, at 160 trillion kilometers (99 trillion miles); the white
Vega, at 204 trillion kilometers (126-1/2 trillion miles); Capella, at
276 trillion kilometers (171 trillion miles); and the Pole-Star at 344
trillion kilometers (213-1/2 trillion miles). The light that flies
through Space at a velocity of 300,000 kilometers (186,000 miles) per
second, takes thirty-six years and a half to reach us from this distant
sun: _i.e._, the luminous ray we are now receiving from Polaris has been
traveling for more than the third of a century. When you, gentle reader,
were born, the ray that arrives to-day from the Pole-Star was already
speeding on its way. In the first second after it had started it
traveled 300,000 kilometers; in the second it added another 300,000
which at once makes 600,000 kilometers; add another 300,000 kilometers
for the third second, and so on during the thirty-six years and a half.
If we tried to arrange the number 300,000 (which represents the distance
accomplished in one second) in superposed rows, as if for an addition
sum, as many times as is necessary to obtain the distance that
separates the Pole-Star from our Earth, the necessary operation would
comprise 1,151,064,000 rows, and the sheet of paper required for the
setting out of such a sum would measure approximately 11,510 kilometers
(about 7,000 miles), _i.e._, almost the diameter of our terrestrial
globe, or about four times the distance from Paris to Moscow!
Is it not impossible to realize that our Sun, with its entire system, is
lost in the Heavens at such a distance from his peers in Space? At the
distance of the least remote of the stars he would appear as one of the
smallest.
* * * * *
The nearest star to us is [alpha] of the Centaur, of first magnitude, a
neighbor of the South Pole, invisible in our latitudes. Its distance is
275,000 radii of the terrestrial orbit, _i.e._, 275,000 times 149
million kilometers, which gives 41 trillions, or 41,000 milliards of
kilometers (= 25-1/2 trillion miles). [A milliard = 1,000 millions, the
French billion. A trillion = 1,000 milliards, or a million millions, the
English billion. The _French_ nomenclature has been retained by the
translator.] At a speed of 300,000 kilometers (186,000 miles) per second
the light takes four years to come from thence. It is a fine double
star.
The next nearest star after this is a little orb invisible to the
unaided eye. It has no name, and stands as No. 21,185 in the Catalogue
of Lalande. It almost attains the seventh magnitude (6.8). Its distance
is 64 trillion kilometers (39-1/2 trillion miles).