The New Heavens | Page 2

as the "Great Horn" or the "Palace of the Emperors" (Hubble) 27. The
giant star Antares (within the white circle), notable for its red color in
the constellation Scorpio, and named by the Greeks "A Rival of Mars"
(Hubble) 28. Diameters of the Sun, Arcturus, Betelgeuse, and Antares
compared with the orbit of Mars 29. Aldebaran, the "leader" (of the
Pleiades), was also known to the Arabs as "The Eye of the Bull," "The
Heart of the Bull," and "The Great Camel" (Hubble) 30. Solar
prominences, photographed with the spectroheliograph without an
eclipse (Ellerman) 31. The 150-foot tower telescope of the Mount
Wilson Observatory 32. Pasadena Laboratory of the Mount Wilson
Observatory 33. Sun-spot vortex in the upper hydrogen atmosphere
(Benioff) 34. Splitting of spectrum lines by a magnetic field (Bacock)
35. Electric furnace in the Pasadena Laboratory of the Mount Wilson
Observatory 36. Titanium oxide in red stars 37. Titanium oxide in
sun-spots 38. The Cavendish experiment 39. The Trifid Nebula in

Sagittarius (Ritchey) 40. Spiral nebula in Ursa Major (Ritchey) 41.
Mount San Antonio as seen from Mount Wilson
CHAPTER I
THE NEW HEAVENS
Go out under the open sky, on a clear and moon-less night, and try to
count the stars. If your station lies well beyond the glare of cities,
which is often strong enough to conceal all but the brighter objects, you
will find the task a difficult one. Ranging through the six magnitudes of
the Greek astronomers, from the brilliant Sirius to the faintest
perceptible points of light, the stars are scattered in great profusion over
the celestial vault. Their number seems limitless, yet actual count will
show that the eye has been deceived. In a survey of the entire heavens,
from pole to pole, it would not be possible to detect more than from six
to seven thousand stars with the naked eye. From a single viewpoint,
even with the keenest vision, only two or three thousand can be seen.
So many of these are at the limit of visibility that Ptolemy's
"Almagest," a catalogue of all the stars whose places were measured
with the simple instruments of the Greek astronomers, contains only
1,022 stars.
Back of Ptolemy, through the speculations of the Greek philosophers,
the mysteries of the Egyptian sun-god, and the observations of the
ancient Chaldeans, the rich and varied traditions of astronomy stretch
far away into a shadowy past. All peoples, in the first stirrings of their
intellectual youth, drawn by the nightly splendor of the skies and the
ceaseless motions of the planets, have set up some system of the
heavens, in which the sense of wonder and the desire for knowledge
were no less concerned than the practical necessities of life. The
measurement of time and the needs of navigation have always
stimulated astronomical research, but the intellectual demand has been
keen from the first. Hipparchus and the Greek astronomers of the
Alexandrian school, shaking off the vagaries of magic and divination,
placed astronomy on a scientific basis, though the reaction of the
Middle Ages caused even such a great astronomer as Tycho Brahe

himself to revert for a time to the practice of astrology.
EARLY INSTRUMENTS
The transparent sky of Egypt, rarely obscured by clouds, greatly
favored Ptolemy's observations. Here was prepared his great star
catalogue, based upon the earlier observations of Hipparchus, and
destined to remain alone in its field for more than twelve centuries,
until Ulugh Bey, Prince of Samarcand, repeated the work of his Greek
predecessor. Throughout this period the stars were looked upon mainly
as points of reference for the observation of planetary motions, and the
instruments of observation underwent little change. The astrolabe,
which consists of a circle divided into degrees, with a rotating
diametral arm for sighting purposes, embodies their essential principle.
In its simple form, the astrolabe was suspended in a vertical plane, and
the stars were observed by bringing the sights on the movable diameter
to bear upon them. Their altitude was then read off on the circle.
Ultimately, the circle of the astrolabe, mounted with one of its
diameters parallel to the earth's axis, became the armillary sphere, the
precursor of our modern equatorial telescope. Great stone quadrants
fixed in the meridian were also employed from very early times. Out of
such furnishings, little modified by the lapse of centuries, was provided
the elaborate instrumental equipment of Uranibourg, the great
observatory built by Tycho Brahe on the Danish island of Huen in 1576.
In this "City of the Heavens," still dependent solely upon the unaided
eye as a collector of starlight, Tycho made those invaluable
observations that enabled Kepler to deduce the true laws of planetary
motion. But after all these centuries the sidereal world embraced no
objects, barring an occasional comet or temporary star, that lay beyond
the vision