ASTRONOMICAL QUANTITIES.

The Sun.

The sun's mean distance from the earth is 92,900,000 miles; his diameter is 866,000 miles; his mean density, as compared with water, is 1·4; his ellipticity is insensible; he rotates on his axis in a period between 25 and 26 days.

The Moon.

The moon's mean distance from the earth is 239,000 miles. The diameter of the moon is 2,160 miles; and her mean density, as compared with water, is 3·5. The time of a revolution around the earth is 27·322 days.

The Planets.

Distance from the Sun in
Millions of Miles.		Periodic Time
in Days.		Mean
Diameter
in Miles.		Axial Rotation.Density
compared
with
Water.
Mean.Least.Greatest.
Mercury36·028·643·387·9693,030(?)6·85(?)
Venus67·266·667·5224·70 7,700(?)4·85
Earth92·991·194·6365·26 7,91823 56 4·095·58
Mars141 128 155 686·98 4,23024 37 22·74·01
Jupiter483 459 505 4,332·6 86,5009 55 —1·38
Saturn886 834 936 10,759 71,00010 14 —0·72
Uranus1,782 1,700 1,860 30,687 31,900Unknown1·22
Neptune2,792 2,760 2,810 60,127 34,800Unknown1·11

The Satellites of Mars.

Mean Distance from Centre
of Mars.		Periodic Time.
hrs.mins.secs.
Phobos5,800 miles73914
Deimos14,500 miles301754

The Satellites of Jupiter.

Mean Distance from Centre
of Jupiter.		Periodic Time.
days.hrs.mins.secs.
New Inner Sattellite Barnard112,500 miles0115722
I.261,000 miles1182734
II.415,000 miles3131342
III.664,000 miles734233
IV.1,167,000 miles16163211

The Satellites of Saturn.

Mean Distance from Centre
of Saturn.		Periodic Time.
days.hrs.mins.secs.
Mimas115,000 miles022376
Enceladus148,000 miles18537
Tethys183,000 miles1211826
Dione235,000 miles217419
Rhea329,000 miles4122512
Titan760,000 miles15224127
Hyperion921,000 miles2163831
Iapetus2,215,000 miles7975640

The Satellites of Uranus.

Mean Distance from Centre
of Uranus.		Periodic Time.
days.hrs.mins.secs.
Ariel119,000 miles2122921
Umbriel166,000 miles432737
Titania272,000 miles8165630
Oberon364,000 miles131176

The Satellite of Neptune.

Mean Distance from Centre
of Neptune.		Periodic Time.
days.hrs.mins.secs.
Satellite220,000 miles521244

INDEX.

A
Aberration of light, [503–512];
and the apparent movements of stars, [504], [507];
Bradley's discoveries, [503];
causes, [507–511;]
circles of stars, [505–507];
dependent upon the velocity of light, [511];
effect on Draco, [505];
telescopic investigation, [510]
Achromatic combination of glasses, [11]
Adams, Professor J.C., and the discovery of Neptune, [324–327], [330–332];
and the Ellipse of the Leonids, [386]
Aërolite, the Chaco, [398];
the Orgueil, [399]
Airy, Sir George, [325]
Alban Mount Meteorites, the, [393]
Alcor, [438]
Aldebaran, [209], [418], [419];
spectrum of, [480];
value of velocity of, [484]
Algol, [485], [487]
Almagest, the, [7]
Alphonsus, [92]
Alps, the great valley of the (lunar), [88]
Altair, [424]
Aluminium in the Sun, [50]
Ancients, astronomy of the, [2–7]
Andrews, Professor, and basaltic formation at Giant's Causeway, [407]
Andromeda, [414];
nebula in, [469], [489]
Andromedes, The, shooting star shower, and Biela's comet, [390]
Antares, [423]
Apennines (lunar), [83]
Aphelion, [163]
Aquarius, [215], [413]
Aquila, or the Eagle, [424]
Arago, [326]
Archimedes, [88]
Arcturus, [358], [480];
value of velocity of, [484]
Argelander's Catalogue of Stars, [431], [476]
Argus, [481]
Ariel, [309], [559]
Aristarchus, [90]
Aristillus, [88]
Aristotle, lunar crater named after him, [88];
credulity respecting his writings, [267];
the Moon and the tides and, [535]
Asteroids, [229–244]
Astrea, [328]
Astronomers of Nineveh, [156]
Astronomical quantities, [558]
Astronomy, ancient, [2–7;]
Galileo's achievements in, [10];
the first phenomenon of, [2]
Athenæum, the, and Sir John Herschel's letter on Adams's share in the discovery of Neptune, [330]
Atmosphere, height of the Earth's, [100]
Attraction, between the Moon and the Earth, [75];
between the planets, [148];
between the Sun and the planets, [144], [148];
of Jupiter, [248], [249];
producing precession, [498]
Auriga, [414], [489]
Aurora borealis, [42]
Autolycus, [88]
Auwers and star distances, [449];
and the irregularity in movement of Sirius, [427]
Axis, Polar, [196], [497];
precession and nutation of the Earth's, [492–502]
B
Backlund, and Encke's comet, [349], [351]
Barnard, Professor E.E., and Saturn, [271], [278], [282];
and Titan, [294];
and the comet of 1892, [355];
and the Milky Way, [475]
Beehive, the, [422]
Belopolsky, M., and Binaries, [487], [488]
Benares meteorite, the, [392]
Bessel, and Bradley, [501];
and the distance of 61 Cygni, [446], [448], [449];
and the distances of stars, [442];
and the irregular movements of Sirius, [426];
receives gold medal of Royal Astronomical Society, [442]
Betelgeuze, [209], [418], [419], [482];
value of velocity of, [484]
Biela's comet, and Sir John
Herschel, [357];
and the Andromedes, [390]
Binaries, spectroscopic, [487]
Binocular glass, [27]
Biot and the L'Aigle meteorites, [392]
Bode's law, [230];
list of double stars, [435]
Bond, Professor, and Saturn's satellites, [296];
and the nebula in Orion, [469];
and the third ring of Saturn, [280]
Boötes, [422]
Bradley, and nutation, [501];
and the aberration of light, [503];
his observations of Uranus, [312]
Bredichin, Professor, and the tails of comets, [365], [366], [367]
Breitenbach iron, the, [397]
Bristol Channel, tides in the, [538]
Brünnow, Dr., observations on the parallax of 61 Cygni, [449]
Burial of Sir John Moore, [72]
Burnham, Mr., and the orbit of Sirius, [427];
his additions to the known number of double stars, [439]
Butler, Bishop, and probability, [460]
Butsura meteorite, [397]
C
Cadmium in the Sun, [50]
Calais, tides at, [536]
Calcium in the Sun, [50]
Campbell, Mr., and Argus, [481];
and Mars, [223]
Canals on Mars, [220]
Cancri [20], [154]
Cancri, ζ, [154]
Cancri, θ, [154]
Canis major, [419]
Canopus, [422]
Cape Observatory, [27]
Capella, [414], [480], [487]
Carboniferous period, [518]
Cardiff, tides at, [538]
Cassini, J.D., and double stars, [434];
and Saturn's satellites, [294];
and the rings of Saturn, [278]
Cassiopeia, [412]
Castor, [420], [487];
a binary star, [437];
revolution of, [437]
Catalogues of stars, [310], [311];
Messier's, [529]
Catharina, [92]
Centauri, α, [422];
Dr. Gill's observations of, [451];
Henderson's measurement of distance of, [442], [451]
Ceres, [231], [232], [238];
and meteorites, [404], [405]
Chaco meteorite, the, [398]
Chacornac, and the lunar crater Schickard, [90]
Challenger, the cruise of the, and magnetic particles in the Atlantic, [408]
Challis, Professor, [326];
his search for Neptune, [327], [328], [331], [332]
Chandler, Mr., and Algol, [485]
Charles's Wain, [28]
Chepstow, tides at, [538]
Chéseaux, discoverer of comet of 1744, [367]
Chicago, telescope at Yerkes Observatory, [16]
Chladni and the meteorite of Siberia, [392]
Chromium in the Sun, [50]
Chromosphere, the, [54]
Chronometers tested by the Moon, [80]
Clairaut and the attraction of planets on comets, [342], [343]
Clavius, [91];
and Jupiter's satellites, [267]
Clock, astronomical, [23]
Clusters, star, [461–464]
Cobalt in the Sun, [50]
Coggia's comet, 1874, [337]
Colour of light and indication of its source, [46]
Colours, the seven primary, [45]
Columbiad, the, [401]
Columbus, [7]
Comets, [112], [149], [250], [336];
and the spectroscope, [355];
attraction from planets, [342], [360];
Biela's, [357];
Biela's and the Andromedes, [390];
Clairaut's investigations, [342], [343];
Coggia's, [337];
Common's (1882), [354];
connection of, with shooting star showers, [388];
constitution of, [336];
containing sodium and iron, [356];
Donati's (1858), [353], [358], [366];
eccentricity of, [360];
Encke's, [344–352;]
existence of carbon in, [356], [367];
gravitation and, [343], [348];
Halley's investigations about, [341–344];
head or nucleus of, [337];
Lexell's, [370];
mass of, [359];
movements of, [336];
Newton's explanations of, [338];
non-periodic, [353–356];
of 1531, [341];
of 1607, [341];
of 1681, [338], [339];
of 1682, [341];
of 1744 (Chéseaux's), [367];
of 1818, [345];
of 1843, [352];
of 1866, [388];
of 1874, [337];
of 1892, [355];
origin of, [369];
parabolic orbits of, [338–340], [360];
periodic return of, [338–341];
shape of, [336];
size of, [337];
tailless, [370];
tails of, [337], [361];
Bredichin's researches, [365];
Chéseaux's, [367];
composition of, [365], [369];
condensation of, [369];
electricity and, [368];
gradual growth of, [363];
law of direction of, [362];
repelled by the Sun, [364];
repulsive force of, [364], [368];
various types of, [365];
Tebbutt's (1881), [353];
tenuity of, [357]
Common, Dr., constructor of reflectors, [21];
and the comet of 1882, [354];
and the nebula in Orion, [469]
Cook, Captain, and the transit of Venus, [184]
Copeland, Dr., and Schmidt's star, [489];
and the lunar crater, Tycho, [92];
and the spectra of nebula, [473];
and the transit of Venus, [189]
Copernicus and Mercury, [156];
confirmation of his theory by the discovery of Jupiter's satellites, [267];
his theory of astronomy, [7];
lunar crater called after him, [89]
Copper in the Sun, [50]
Cor scorpionis, [423]
Corona Borealis, [423], [488]
Corona of Sun, during an eclipse, [62–64], [151]
Coronium, [64]
Cotopaxi and meteorites, [401]
Crab, the, [422]
Crabtree, and the transit of Venus, [180]
Crape ring of Saturn, [281]
Craters in the Moon, [83–85], [87–98]
Critical velocity, [103], [104], [237]
Crown, the, [423]
Cryptograph of Huyghens, the, [277]
Cygni, β, [439]
Cygni 61, annual parallax of, [450];
Bessel's measurement of distance of, [442], [446], [447];
Brünnow's observations of, [449];
distance from the Sun of, [452];
disturbing influence of, [452];
double, [446];
Professor A. Hall's measurement of, [449];
Professor Pritchard's photographic researches concerning, [449];
proper motion of, [446];
Struve's observations of, [448], [449];
velocity of, [452]
Cygnus, [424]
Cyrillus, [92]
Cysat, and the Belt of Orion, [467]
D
D line in solar spectrum, [48]
Darwin, Professor G.H., and tidal evolution, [531]
Dawes, Professor, and Saturn's third ring, [281]
Day, length of, and the Moon, [542];
and the tides, [541]
Deimos, [226], [558]
Denebola, [423]
Diffraction, [56]
Dione, [559]
Dispersion of colours, [47]
Distances, astronomical, [558], [559]
Doerfel, and comets, [339]
Dog star (see [Sirius])
Dog, the Little, [420]
Donati's comet, [353], [358];
tails, [366]
Double stars, [434–440]
D Q, [236]
Draco, nebula in, [470]
Dragon, the, [415]
Draper, Professor, and the nebula in Orion, [469]
Dunsink Observatory, [12], [184], [447], [449]
Dynamical stability, [547];
theory of Newton, [214]
Dynamics and the Earth-Moon system, [546]
Dynamics, Galileo the founder of, [10]
E
Eagle, the, [424]
Earth, The, ancient ideas respecting, [3];
annual movement of, and the apparent movement of the stars, [507], [512];
attraction of Jupiter, [319];
attraction of on Encke's comet, [350];
attraction of, on the Leonids, [386];
attraction of Saturn, [319];
attraction of the Moon, [75], [497];
attraction of the Sun, [496];
axial rotation of, [558];
carboniferous period on, [518];
change of climate on, [518];
composition of, [496];
contact of atmosphere of, with meteors, [377–379];
density of, [558];
diameter of, [558];
distance of, from Mars, [213];
distance of, from the Moon, [73], [558];
distance of, from the Sun, [31], [114], [184], [240], [265], [351], [512], [558];
energy from rotation of, [540];
formerly a molten globe, [200], [201];
geological records and, [517];
glacial period on, [518];
gravitation and, [204], [206], [207], [497];
heat in the interior of, [94], [197], [198], [251], [514];
how it is measured, [193–196];
its mass increasing owing to the fall of meteoric matter, [408];
its oceans once vapour, [251];
once in immediate proximity to the Moon, [542];
orbit of, [114];
orbit of, its elliptic form, [139];
path of deranged by Venus and Mars, [319];
periodic time of, [558];
plane of orbit of, [309];
polar axis of, [196], [492–502];
position of, relatively to the Sun and the Moon, [76], [77];
precession and nutation of axis of, [492–502];
radius of, [193], [512];
rotation of, [75], [196], [200], [494], [496];
shape of, [192], [195], [197], [201], [207];
size of, compared with Jupiter, [119],
and with other planets, [119];
size and weight of, compared with those of the Sun, [30],
and Moon, [74], [75];
velocity of, [115], [139], [146], [512],
and periodic time, [143];
volcanic outbreaks on, [197],
and the origin of meteorites, [405];
weight of, [202], [248],
as compared with Saturn, [271], [272]
Earthquakes, astronomical instruments disturbed by, [24]
Eccentricity of planetary ellipses, [136], [211]
Eclipse of Jupiter's satellites, [261], [262], [265–267]
Ellipse of the Moon, [77–80];
of the Sun, [53]
Eclipses, ancient explanations of, [6];
calculations of the recurrence of, [79], [80]
Ecliptic, the,

[5], [233];
Pole of the, [493], [500], [505]
Electric Light, the, [44]
Ellipse, the, [136];
eccentricity of, [137];
focus of, [137];
Kepler's discoveries respecting, [136], [138], [142–144], [505];
the form which the orbit of a planet takes, [136];
the parallactic, [444];
variety of form of, [139]
Enceladus, [559]
Encke, and the distance of the Sun from the Earth, [147], [184];
his comet, [344–352]
Encke's comet, [344–352];
approach to Jupiter of, [349];
and Mercury, [349];
and the Sun, [346];
diminution in periodic time of, [351];
distance from Mercury of, [347];
disturbed by the Earth, [350],
and by Mercury, [348];
irregularities of, [347], [351];
orbit of, [346];
periodical return of, [351];
Von Asten's calculations concerning, [349–350]
Energy supplying the tides, [539]
Ensisheim meteorite, the, [393]
Equatorial diameter, [196], [497];
telescope, [14]
Eratosthenes, [89]
Eros, [236]
Eruptions, [197]
Evening star, [109], [169]
Eye, structure of the, [10]
F
Faculæ of the Sun, [37]
Fire ball of 1869, [375]
Fire balls, [374]
"Fixed" stars, [503]
Flamsteed, first Astronomer-Royal, [311];
his Historia Cœlestis, [311]
Focus of planetary ellipse, [137–139]
Fomalhaut, [413]
Fraunhofer, [478]
Fraunhofer lines, [48]
Fundy, Bay of, tides in, [538]
G
Galileo, achievements of, [10];
and Jupiter's satellites, [267];
and Saturn's rings, [273], [274];
and the Pleiades, [418]
Galle, Dr., and Neptune, [328–330]
Gassendi, and the transit of Mercury, [164];
and the transit of Venus, [178];
lunar crater named after him, [90]
Gauss, and the minor planet Ceres, [232]
Gemini, constellation of, [303], [420]
Geminids, the, [400]
Geologists and the lapse of time, [453]
Geometers, Oriental, [5]
Geometry, cultivation by the ancients of, [6]
George III. and Sir W. Herschel, [299], [306]
Giant's Causeway, [407]
Gill, Dr. D., [27];
and Juno, [243];
and the minor planets, [242];
and the parallax of α Centauri, [451];
and the parallax of Mars, [214]
Glacial period, [518]
Gravitation, law of, [122–149];
and binary stars, [437];
and precession, [497];
and the Earth's axis, [495], [497], [499];
and the parabolic path of comets, [340];
and the periodical return of comets, [343];
and the weight of the Earth, [203], [204];
illustrated by experiments, [123], [124], [127], [129–132];
its discovery aided by lunar observations, [108], [125];
its influence on the satellites, [149];
its influence on stars, [149];
its influence on tides, [149];
Le Verrier's triumphant proof of, [330];
Newton's discoveries, [125], [126], [147];
on the Moon, [96];
universality amongst the heavenly bodies, [128], [373]
Great Bear, [27], [28], [241];
configuration, [410];
double star in the, [438];
positions of, [409], [411]
Green, Mr., and Mars, [220]
Greenwich Observatory, [26], [311]
Griffiths, Mr., and Jupiter, [252]
Grimaldi, [90]
Grubb, Sir Howard, [14]
"Guards," the, [412]
Gulliver's Travels and the satellites of Mars, [228]
H
Hadley's observations of Saturn, [282]
Hall, Professor Asaph, and the satellites of Mars, [225]
Halley, and the periodicity of comets, [341–343];
and the transit of Venus, [180]
Heat, bearings on astronomy, [513];
in the interior of the Earth, [197–199], [514];
of the Sun, [515–526]
Heliometer, the, [243]
Helium, [55]
Henderson, and the distance of α Centauri, [442], [451]
Hercules, star cluster in, [269], [462]
Herodotus (lunar crater), [90]
Herschel, Caroline, [299], [465]
Herschel, Sir John, address to British Association, [328];
address on the presentation of gold medal to Bessel, [443];
and Biela's comet, [357];
and nebulæ, [464];
letter to Athenœum on Adams's share in the discovery of Neptune, [330]
Herschel, Sir W., and double stars, [435], [436];
and Saturn, [279];
and Saturn's satellites, [295];
and the Empress Catherine, [301];
and the movement of solar system towards Lyra, [457];
discovery of satellite of Uranus by, [308], [309];
discovery of Uranus by, [305], [308];
early life of, [299];
friendship with Sir W. Watson of [302];
he makes his own telescopes, [301];
"King's Astronomer," [307];
method of making his telescopes, [302];
musical talent of, [299];
organist of Octagon Chapel, Bath, [300];
pardon for desertion from George III., [299];
passion for astronomy of, [300], [301];
relinquishes musical profession, [307];
sidereal aggregation theory of, [529];
study of the nebulæ by, [464–465], [529]
Herschelian telescope, [19]
Historia Cœlestis, [311]
Hœdi, the, [414]
Holmes's, Mr., comet (1892), [355]
Horrocks, and the transit of Venus, [179]
Howard, Mr., and the Benares meteorite, [392]
Huggins, Sir W., [479], [483];
and nebulæ, [472]
Huyghens, and Saturn's rings, [275–278];
discovers first satellite of Saturn, [293]
Hyades, the, [419]
Hydrogen in Sirius and Vega, [479];
in the Sun, [50]
Hyginus, [93]
Hyperion, [559]
I
Iapetus, [559]
Iberians, the, [3]
Inquisition, the, and Galileo, [10]
Iris, [242]
Iron, dust in the Arctic regions, [408];
in the Sun, [50];
of meteorites, the, [396];
spectrum of, [50]
J
Janssen, M., [34], [53];
and the transit of Venus, [177]
Juno, [233], [238]
Jupiter, ancient study of, [6];
and the Leonids, [386];
attraction of, [248];
axial rotation of, [558];
belts of, [252];
brilliancy of, [257];
composition of, [250];
covered with an atmosphere of clouds, [253], [254];
density of, [558];
diameter of, [247], [558];
distance from the Earth of, [110], [111];
distance from the Sun of, [246], [558];
habitability of, [257];
heat received from the Sun by, [256];
internal heat of, [252], [256], [515];
lack of permanent features of, [253];
lack of solidity of, [248], [253], [254];
moment of momentum of, [554], [555];
occultation of, [255];
orbit of, [114], [115], [246];
path of, perturbed by the attraction of Saturn, [316];
periodic time of, [558];
a planet, or "wanderer," [111];
red spot in 1878, [253];
revolution of, [246];
rotation of, [201], [202];
satellites of, [247], [249], [257–261], [265], [559];
satellites of, and gravitation, [266];
satellites of, and the Copernican theory, [267];
shadow from satellites of, [257];
shape of, [201], [202], [247], [252];
size of, compared with the Earth, [19], [246], [248],
and other planets, [114];
and the Sun, [114];
storms on, [256];
tides on, [555];
weight of, [248], [250],
and Encke's comet, [350]
K
Keeler, Professor, and Saturn's ring, [288]
Kempf, Dr., and the Sun's velocity, [484]
Kepler, and comets, [360];
and laws of planetary motion, [10];
and meteors, [386];
and the orbit of Mars, [209];
explanation of his laws, [147], [148], [533];
his discovery of the shape of the planetary orbits, [136], [138];
his first planetary law, [138];
lunar crater called after him, [90];
prediction of the transit of Venus and Mercury, [163], [178];
second law, [141];
third law, [142]
Kids, the, [414]
Kirchhoff, and spectrum analysis, [478]
Kirkwood, Professor, and the movements of Saturn's satellites, [296]
Klinkerfues, Professor, [390]
L
Lagrange, and the theory of planetary perturbation, [320–322];
his assumption of planetary rigidity, [531]
L'Aigle meteorites, the, [392]
Lalande, and Neptune, [332], [333]
Landscapes, lunar, [98]
Lane, Mr. J. Homer, [522]
Laplace, and the nebular theory, [526];
and the satellites of Jupiter, [266];
and the theory of planetary perturbation, [320]
Lassell, Mr., and Saturn's eighth satellite, [296];
discovers Neptune's satellite, [334]
Law of gravitation (see [Gravitation])
Laws of Planetary Motion (see [Planetary Motion])
Lead in the Sun, [50]
Ledger, Mr., and Mercury, [163]
Leibnitz, lunar mountains named after him, [93]
Lemonnier, and Uranus, [312]
Leo, and shooting stars, [380], [420]
Leonids, attractions of planets on, [386];
breadth of stream of, [387];
change of shape of, [383];
decrease of, [385];
enormous number of, [382];
historical records, [383];
length of stream of, [387];
Le Verrier, and the cause of their introduction into the solar system, [388];
meteor shoal of, [382];
periodic return of, [382];
their connection with comets and Professor, Schiaparelli, [388]
Leonis γ, value of velocity of, [484]
Leverage by equatorial protuberance, [498]
Le Verrier, and Mars, [214];
and the discovery of Neptune, [324–332];
and the introduction of the Leonids into the solar system, [388];
and the weight of Mercury, [349]
Lexell's comet, [370]
Libration, [84]
Lick Observatory, [16]
Light, aberration of, [503–512];
velocity of, [261], [262], [265], [505], [512]
Linné, [87], [94]
Lion, the, [420], [421]
Little Bear, the, [412]
Little Dog, the, [420]
Livy, and meteorites, [393]
Lloyd, Provost, [407]
Lockyer, Sir Norman, and Betelgeuze, [482];
and solar light, [52]
London, tides at, [538]
Louvain, F. Terby, and Titan, [295]
Lowell, Mr., and Mercury, [165]
Lunar tides, [548], [549]
Lyra, motion of solar system towards, [459]
Lyre, the, [424];
Nebula in, [469]
Lyrids, the, [400]
M
Mädler, and the lunar craters, [88], [90], [91]
Magellanic clouds, [463]
Magnesium, colour of flame from, [46];
in the Sun, [50]
Magnetism, connection with Sun spots, [42]
Manganese in the Sun, [50]
Maraldi, and the rings of Saturn, [279]
Mare crisium, [83];
fœcunditatis, [83];
humorum, [83];
imbrium, [83], [98];
nectaris [83];
nubium, [83];
serenitatis, [83];
tranquillitatis, [83];
vaporum, [83]
Mars, ancient study of, [6];
appearance of, through the telescope, [218];
atmosphere of, [222];
axial rotation of, [558];
canals on, [220];
density of, [558];
diameter of, [558];
distance, from the Earth of, [213];
distance from the Sun of, [213], [558];
gravitation on, [225];
Le Verrier's discovery of, [214];
life improbable on, [224];
marking on, [218];
movements of, [211–213];
opposition of, [209–211];
orbit of, [116], [209], [210], [213];
orbit of, and the laws of Kepler, [209];
parallax (1877), and Dr. D. Gill, [214];
periodic time of, [558];
a planet or "wanderer," [111];
"Polar Caps" on, [218], [219];
proximity to the Earth of, [110];
rising and setting of, [209];
rotation of, [218];
satellites of, [225–228], [558];
size of compared with other planets, [116], [216];
tides on, [551];
water and ice on, [219], [224]
Maximilian, Emperor, [393]
Mayer, Tobias, and Uranus, [312]
Measurement of the Earth, [193–196]
Mediterranean, tides in the, [537]
Mercury, ancient study of, [6];
antiquity of its discovery, [155–157];
atmosphere of, [166];
attraction on comets of, [347];
climate of, [163];
comparative proximity to the Earth of, [111];
composition of, [160];
crescent-shaped, [160];
density of, [558];
diameter of, [558];
distance from the Sun of, [151], [558];
habitability of, [163];
movement of, [160], [161];
its elliptic form, [139], [161];
orbit of, [114];
period of revolution of, [161];
periodic appearances of, [158];
periodic time of, [558];
perturbations of, [350];
a planet or "wanderer," [111];
revolution of, [165];
rotation of, and Professor Schiaparelli, [165];
size of, compared with other planets, [116];
surface of, [162];
transit of, [152];
transit of, and Gassendi's observations, [164];
transit of, predicted by Kepler, [163];
velocity of, [162];
weight of, [166], [349]
Meridian circle,

[22], [24]
Messier's Catalogue of Stars, [529]
Meteors (see Stars, [shooting])
Meteorites, [391];
Alban Mount, [393];
ancient accounts, [392], [393];
Benares, [392];
Butsura, [397];
Chaco, [398];
characteristics of, [397];
Chladni's account of discovery in Siberia, [392];
composition of, [397–399];
Ensisheim (1492), [393];
Hindoo account of, [391];
L'Aigle, [392];
not connected with comets, [400];
not connected with star showers, [400];
Orgueil, [399];
origin, [400–408];
Ovifak, [407];
Rowton, [395–396];
Wold Cottage, [392]
Micrometer, [86]
Milky Way, [462–3], [474–6]
Mimas, [559]
Minor planets, [229–244]
Mira Ceti, [430], [482]
Mizar, [438], [486]
Moment of momentum, the, [552–554]
Month of one day, [547]
Moon, The, absence of air on, [85], [99];
absence of heat on, [95];
agent in causing the tides, [70], [535–537];
ancient discoveries respecting, [5];
apparent size of, [73];
attraction to the Earth of, [75];
brightness of, as compared with that of the Sun, [71];
changes during the month of, [71], [74];
chart of surface of, [81];
craters on, [83], [84], [87–98], [514];
density of, [558];
diameter of, [558];
distance from the Earth of, [73], [75], [568];
eclipses of, [6], [77–80];
illustration of the law of gravitation, [96], [131], [133];
landscapes on, [98];
life impossible on, [99];
measuring heights of mountains, etc., of, [85], [86];
micrometer, [86]; motion of, [75];
mountains on, [83], [85], [88], [89], [91], [93];
phases of, [71], [76];
plane of orbit of, [310], [500], [501];
poets and artists and, [72];
pole, [500];
possibility of ejecting meteorites, [402];
possibly fractured off from the earth, [543];
prehistoric tides on, [548], [549];
produces precession, [497–499];
proximity to the Earth of, [73], [75];
receding from the Earth, [545];
relative position of with regard to the Earth and the Sun, [76], [77];
revolution of, round the Earth, [75], [76], [558];
"seas" on, [82], [83];
shadows of, [85];
size of, compared with that of the Earth, [74];
test for chronometers, a, [80];
thraldom of terrestrial tides, [549];
waterless, [100];
weather not a affected by the phases of, [82];
weight of, [74]
Motion, laws of planetary, [138], [141], [142], [147], [148]
Mountains of the Moon, [83], [85], [93]
N
Nasmyth, Mr., and the formation of lunar craters, [95]
Natural History Museum, meteorites, [394]
Nautical Almanack, [189]
Neap Tides, [538]
Nebula, in Andromeda, [469];
annular, in Lyra, [469];
in Orion, [269], [461], [466–469];
colour of, [468];
magnitude of, [468];
nature of, [467];
planetary, in Draco, [470];
simplest type of a, [528];
various grades of, [528]
Nebulæ, [464–472];
condensation, [528];
distances of, [464];
double, [470];
Herschel's labours respecting, [464–465], [528], [529];
number of, [466];
planetary, [470];
self-luminous, [464];
smallest greater than the Sun, [464];
spiral, [470]
Nebular theory, the, [526]
Neptune, [112];
Adams's researches, [324–326], [332];
Challis's observations of, [326–328];
density of, [558];
diameter of, [333], [558];
disc of, [332];
discovery (1846) of, [315];
distance from the Sun of, [334], [558];
Lalande's observations of, [332], [333];
Le Verrier's calculations, [324–332];
moment of momentum of, [554];
orbit of, [117];
periodic time of, [558];
revolution of, [334];
rotation of uncertain, [333];
satellite of, discovered by Mr. Lassell, [559];
size of, compared with other planets, [119];
vaporous atmosphere of, [333];
weight of, [333]
Newall, Mr. H.F., and Capella, [487];
and the values of velocity of stars, [483]
Newcomb, Professor, [9], [264], [267], [522]
Newton, Professor, and meteoric showers, [377], [384]
Newton, Sir Isaac, discovery of gravitation verified Kepler's laws, [144];
dynamical theory, [214];
illustrations of his teaching, [144–147];
law of gravitation and, [125], [126], [537];
parabolic path of comets and, [338–340];
reflecting telescope, [19];
weight of the Earth and, [203]
Nickel in the Sun, [50]
Nineveh, astronomers of, [156]
Nordenskjöld, and the Ovifak meteorite, [407]
Nova Cygni, [431];
brilliancy of, [454];
decline of, [455];
distance of, [456];
parallax of, [455]
November meteors, [376], [377], [379]
Nutation, and Bradley, [501]
O
Oberon, [309], [559]
Object-glasses, [11], [12], [14], [16], [19]
Observatories, [9–28]
Observatory, Cape of Good Hope, [27];
Dunsink, [12], [184];
Greenwich, [26], [314];
Lick, [16];
Paris, [22];
Uraniborg, [10];
Vienna, [14];
Washington, [226];
Yerkes, [16]
Occultation, [102], [215]
Oceanus Procellarum, [83]
Opera-glass, [27], [28]
Opposition of Mars, [209]
Orbital moment of momentum, [552]
Orbits of planets, [114], [115], [117];
dimensions, [139–143];
elliptical form, [138–140];
minor planets, [232], [234], [239];
not exactly circles, [135];
of satellites of Uranus, [310];
Sun the common focus, [139]
Orgueil meteorite, the, [399]
Orion, [4], [418]
Orion, belt of, [418], [467];
brilliancy of, [418];
nebula in, [269], [461], [466–469]
Orionis, α, [418], [482]
Orionis, θ, a multiple star, [318], [467]
Ovifak meteorite, the, [407]
P
Palisa and the minor planets, [234]
Pallas, [233], [238]
Parabolic path of comets, [338–340]
Parallactic ellipse, [444]
Parallax, [181], [182], [214], [443];
of stars, [507]
Paris telescope, [22], [23]
Pegasus, great square of, [413], [414]
Peg-top, the, and the rotation of the Earth, [494]
Pendulum for determining the force of the Earth's attraction, [205]
Penumbra of Sun-spot, [51]
Perihelion, [163]
Periodic times of planets, [139–143], [558]
Periodicity of Sun-spots, [41]
Perseids, [400]
Perseus, [415], [416], [429];
sword-handle, [462]
Perturbation, planetary, [317–324], [346]
Perturbations, theory of, [296]
Petavius, [93]
Peters, Professor, and charts of minor planets, [234];
and the derangement of Sirius, [427]
Phases of the Moon, [71], [76]
Phobos, [226], [551], [558]
Photography, and practical astronomy, [25];
and the distance of 61 Cygni, [449];
Dr. Roberts and the nebula in Andromeda, [469];
Mr. Common and the nebula in Orion, [469];
Sir W. Huggins and the spectra of nebulæ, [473]
Photosphere, the, [37], [54]
Physical nature of the stars, [477]
Piazzi, discoverer of the first known minor planet, [203]
Pickering, Professor, [218], [220], [255], [265];
and Betelgeuze, [482];
and planetary nebulæ, [474];
and Saturn's satellites, [296];
and spectroscopic binaries, [486], [487]
Pico, [89]
Planetary motion, Kepler's laws of, [138], [141], [142], [147], [148]
Planetary nebulæ, [470]
Planetary perturbation, [317–324]
Planets, ancient ideas respecting, [2], [6];
approximate number of, [112];
attract each other, [148], [317];
attracted by comets,[360];
Bode's law, [230];
comparative sizes of, [118], [119];
distance of, from the Earth, [109–111];
distance of, from the Sun, [558];
how distinguished from stars, [111];
irregularity of motions of, [317–324];
Lagrange's theory of rigidity of, [531];
light of, derived from the Sun, [113];
minor, [229–244];
orbits of the four giant, [117];
orbits of the four interior, [114];
orbits have their focus in the centre of the Sun, [139];
orbits not exactly circles, [135];
orbits take the form of an ellipse, [136–138];
origin of, as suggested by the nebular theory, [526];
periodic times of, [139–143], [558];
relative distances of, [229];
uniformity of direction in their revolution, [120], [322];
velocity of, [139–142], [144], [146], [237]
Plato (lunar crater), [89]
Pleiades, [241], [416];
invisible in the summer, [416]
Pliny, the tides and the Moon, [535]
Plough, the, [28]
Pogson, Mr., [390]
Pointers in the Great Bear, [28], [411]
Polar axis, [196]
Polar caps on Mars, [218], [219]
Pole, the, distance of from Pole Star lessening, [494];
elevation of, [195];
movement of, [492];
near α Draconis, [494];
near Vega or α Lyra, [494]
Pole Star, [194];
belongs to the Little Bear, [412];
distance of, from the pole of the heavens, [412], [492], [494];
position of, [411];
slow motion of, [412]
Pollux, [420], [480];
value of velocity of, [484]
Pons, and the comet of 1818, [345]
Posidonius, [87]
Potassium in the Sun, [50]
Præsepe, [422]
Precession and nutation of the Earth's axis, [492–502]
Proctor, and the stars in Argelander's atlas, [476]
Prism, the, [45];
its analysing power, [46]
Pritchard, Professor, stellar photographic researches of, [449]
Procyon, [420];
value of velocity of, [484]
Prominences on the Sun, [53–59]
Ptolemy, his theory of astronomy, [6];
lunar crater named after him, [92]
Q
Quarantids, the, [400]
R
Radius of the Earth, [193], [512]
Rainbow, the, [45]
Ram, the, [420]
Reflectors, [19], [21], [25]
Refraction by the prism, [45]
Refractors, [11], [14], [16]
Regulus, [421], [479]
Reservoir formed from tidal water, [538]
Retina, the, and the telescope, [10], [11]
Rhea, [559]
Rigel, [418], [420], [480]
Rigidity of the planets, [532], [533]
Roberts, Dr. Isaac, and the nebula in Andromeda, [469];
and the nebula in Orion, [469]
Roemer, and the velocity of light, [261]
Romance, planet of, [151–154]
Rosse telescope, the, [19], [20], [468], [470]
Rotational moment of momentum, [553]
Rowland, Professor, and spectral lines, [491]
Rowton Siderite, [395]
Royal Astronomical Society and Bessel, [442]
S
Sappho, [242]
Satellites of Jupiter, [249], [250], [257–261], [266], [559];
confirmation of the Copernican theory, [267]
Satellites of Mars, [209], [225–228], [551], [558]
Satellites of Neptune, [334], [559]
Satellites of Saturn, [559];
Bond's discoveries, [296];
Cassini's discoveries, [294];
distances, [559];
Herschel's discoveries, [295];
Huyghens' discovery, [293];
Kirkwood's deduction, [296];
Lassell's deduction, [296];
movements, [296];
origin as suggested by the nebular theory, [526]
Satellites of Uranus, [308], [309], [310], [559]
Saturn, ancient study of, [6];
attraction on Uranus, [322];
axial rotation of, [558];
beauty of, [209];
comparative proximity to the Earth of, [110];
density of, [558];
diameter of, [271], [558];
distance of, from the Sun, [268], [271], [558];
elliptic path of, [271];
gravitation paramount, [283];
internal heat of, [272], [515];
Leonids and, [386];
low density of, [272];

moment of momentum of, [554];
motion of, [271];
orbit of, [117], [118];
path of, perturbed by the attraction of Jupiter, [316];
periodic time of, [558];
period of revolution of, [269];
picturesqueness of, [291];
position of, in the solar system, [269];
rings of, [269];
rings, Bonds discovery, [280];
rings, Cassini's discovery, [278];
rings, consistency, [286];
rings, Dawes's discovery, [281];
rings, Galileo's discovery, [273], [274];
rings, Hadley's observations, [282];
rings, Herschel's researches, [279];
rings, Huyghens' discovery, [275–278];
rings, Keeler's measurement of the rotation, [288];
rings, Maraldi's researches, [279];
rings, rotation of, [285], [288];
rings, spectrum of, [291];
rings, Trouvelot's drawing, [278];
satellites of, [293], [294], [295], [296], [559];
size of, compared with other planets, [119], [269], [272];
spectrum of, [291];
unequal in appearance to Mars and Venus, [269];
velocity of, [271];
weight of, compared with the Earth, [272]
Savary and binary stars, [436]
Schaeberle, Mr., and Mars, [224]
Scheiner, and the values of velocity of stars, [483];
observations on Sun-spots, [36]
Schiaparelli, Professor, and Mars, [220];
and the connection between shooting-star showers and comets, [388];
and the rotation of Mercury, [165]
Schickard, [90]
Schmidt, and Nova Cygni, [454], [489];
and the crater Linné, [87];
and the Leibnitz Mountains, [93]
Schröter, and the crater Posidonius, [87]
Schwabe, and Sun-spots, [40]
Seas in the Moon, [82]
Secchi, and stellar spectra, [479]
Shoal of shooting stars, [377];
dimensions, [377]
Shooting stars (see Stars, [shooting])
Sickle, the, [421]
Sidereal aggregation theory of Sir W. Herschel, [529]
Siderite, Rowton, [395]
Sinus Iridum, [83]
Sirius, change in position of, [425];
companion of, [427], [428];
exceptional lustre of, [110];
irregularities of movement of, [426];
larger than the Sun, [110];
most brilliant star, [419];
periodical appearances of, [157];
proper motion of, [425];
spectrum of, 479;
velocity of, [426];
weight of, [427]
Smyth, Professor C.P., [493]
Sodium, colour of flame from, [49];
in the Sun, [50]
Solar corona, prominences etc. (see under [Sun])
Solar system, [107–121];
Copernican exposition of the, [7];
influence of gravitation on, [149];
information respecting, obtained by observing the transit of Venus, [174];
island in the universe, [121];
minor planets, [229–244];
moment of momentum, [554];
movement of, towards Lyra, [457];
origin of, as suggested by the nebular theory, [526];
position of Saturn and Uranus in, [297], [305]
South, Sir James, [12]
Spectra of stars, [479]
Spectro-heliograph, [58]
Spectroscope, [43–56];
detection of iron in the Sun by the, [50]
Spectroscopic binaries, [487]
Spectrum analysis, [47];
dark lines, [49], [50];
gaseous nebulæ, [474];
line D, [48], [49]
Speculum, the Rosse, [20]
Spica, [423], [487]
Spider-threads for adjusting the micrometer, [86];
for sighting telescopes, [22]
Spots on the Sun, [36–43];
connection with magnetism, [42];
cycles, [41];
duration, [41];
epochs of maximum, [42];
motion, [36];
period of revolution, [40];
Scheiner's observations, [36];
zones in which they occur, [39]
Star clusters, [461–464];
in Hercules, [462];
in Perseus, [462]
Stars, apparent movements due to precession, nutation, and aberration, [504];
approximate number of, [28];
attraction inappreciable, [316];
catalogues of, [310], [311], [409], [431];
charts of, [325], [328];
circular movement of, [505–507]
Stars, distances of, [441];
Bessel's labours, [442–449];
Henderson's labours, [442];
method of measuring, [443–445];
Struve's work, [442], [448], [449];
parallactic ellipse, [444–449]
Stars, double, [434];
Bode's list, [435];
Burnham's additions, [439];
Cassini, [434];
Herschel, [435], [436];
measurement, [435], [436];
revolution, [436];
Savary, [436];
shape of orbit, [436];
variation in colour, [438]
Stars, elliptic movement of, [506];
gravitation and, [149];
how distinguished from planets, [111];
physical nature of, [477];
probability of their possessing a planetary system, [121];
real and apparent movements of, [504];
really suns, [32], [121]
Stars, shooting, attractions of the planets, [386];
connection with comets, [388–390];
countless in number, [372];
dimensions of shoal, [377];
features of, [373];
length of orbit, [387];
orbit, [378];
orbit, gradual change, [386];
period of revolution, [384];
periodic return, [378], [379];
shower of November, 1866, [377], [379–380];
shower of November, 1866, and Professor Adams, [384], [386];
shower of November, 1866, radiation of tracks from Leo, [380];
shower of November, 1872, [389];
showers, [376];
showers and Professor Newton, [377];
track, [377];
transformed into vapour by friction with the Earth's atmosphere, [374], [376];
velocity, [373], [386]
Stars, spectra of, [479];
teaching of ancients respecting, [3];
temperature of, [515];
temporary, [430], [488];
values of velocity of, [484];
variable, [429]
Stoney, Dr. G.J., [387]
Strontium, flame from, [46];
in the Sun, [50]
Struve, Otto, and the distance of Vega, [442], [447];
and the distance of 61 Cygni, [448], [449]
Sun, The, and the velocity of light, [265];
apparent size of, as seen from the planets, [117], [118];
as a star, [32];
axial rotation of, [558];
compared with the Earth, [29];
connection of, with the seasons, [4];
corona of, during eclipse, [62–64];
density of, [65], [558];
diameter of, [558];
distance of, from Mars, [213];
distance of, from Saturn, [271];
distance of, from the Earth, [31], [114], [184], [240], [558];
eclipse of, [6], [53];
ellipticity of, [558];
faculæ on surface of, [37];
focus of planets' orbits, [138];
gradually parting with its heat, [95];
granules on surface of, [34];
heat of, and its sources, [515–526];
heat of, thrown on Jupiter, [256];
minor planets and, [240];
movement of, towards Lyra, [457];
nebular theory of its heat, [526];
photographed, [34];
precession of the Earth's axis, [497];
prominences of, [53–59];
relation of, to the Moon, [71];
rising and setting of, [2];
rotation of, [40], [201];
size of, [29];
spectrum of, [48];
spots on, [36–43];
spots, connection with magnetism, [42];
storms and convulsions on, [42], [43];
surface of, gaseous matter, [34];
surface of, mottled, [34];
teaching of early astronomers concerning, [3–7];
temperature of, [30], [31], [516];
texture of, [34];
tides on, [530];
velocity of, [484];
weight of, compared with Jupiter, [250], [350];
zodiacal light and, [67];
zones on the surface of, [39]
Sunbeam, revelations of a, [44]
Swan, the, [424], [439], [445]
Sword-handle of Perseus, [462]
Syrtis major, [222]
T
Taurus, constellation of, [231], [419]
Tebbutt's comet, [353]
Telescope, construction of the first, [10];
equatorial (Dunsink), [12–14], [185];
Greenwich, [26];
Herschelian, [19];
Lick, [16], [19];
Paris, [22], [23];
reflecting, [19], [21];
refracting, [11], [14];
Rosse, [19], [20], [468], [470];
sighting of a, [23];
structure of the eye illustrates the principle of the, [10];
Vienna, [14–16];
Washington, [226];
Yerkes, [16]
Temporary stars, [430], [488]
Tethys, [559]
Theophilus, [92]
Tides, The, actual energy derived from the Earth, [539];
affected by the law of gravitation, [149], [535];
affected by the Moon, [70], [535–537];
at Bay of Fundy, [538];
at Cardiff, [538];
at Chepstow, [538];
at London, [538];
at St. Helena, [538];
excited by the Sun, [537];
formation of currents, [538];
in Bristol Channel, [538];
in Mediterranean, [537];
in mid-ocean, [538];
Jupiter and, [552];
length of the day and, [541];
lunar, [548], [549];
moment of momentum and, [552];
neap, [537];
rotation of the Earth, and revolution of the Moon, [549];
satellites of Mars, [551];
solar, [550];
spring, [537];
variations in, [538];
waste of water power, [538];
work effected, [539]
Tin in the Sun, [50]
Titan, [294], [295], [559]
Titania, [309], [559]
Transit of Mercury, [152], [163], [164]
Transit of Venus, [152];
Captain Cook, [184];
Copeland's observations of, [189];
Crabtree's observations of, [180];
Gassendi's observations of, [178];
Halley's method, [180], [181];
Horrocks' observations of, [179], [180];
importance of, [173];
Kepler's prediction of, [163];
observations of, at Dunsink, [184–188]
Transit of Vulcan, [152–153]
Triesnecker, [84], [93]
Trouvelot, Mr. L., and Saturn's rings, [278]
Tschermak, and the origin of meteorites, [400], [401]
Tycho (lunar crater), [91]
Tycho Brahe, and the Observatory of Uraniborg, [9], [10], [430]
U
Umbra of Sun-spot, [51]
Umbriel, [309], [559]
Unstable dynamical equilibrium, [543]
Uraniborg, Observatory of, [10]
Uranus, [112];
attraction of Saturn, [322];
Bradley's observations of, [312];
composition of, [308];
density of, [558];
diameter of, [308], [558];
diameter of orbit of, [305];
disc of, [308];
discovery of, by Herschel, [305], [308];
distance from Sun of, [558];
ellipse of, [313];
first taken for a comet, [304];
Flamsteed's observations of, [311], [312];
formerly regarded as a star, [311], [312];
investigations to discover a planet outside the orbit, [323–324];
irregular motion of, [314], [323];
Lemonnier's observations of, [312];
Leonids and, [386];
Mayer's observations of, [312];
moment of momentum of, [554];
orbit of, [117], [310];
periodic time of, [558];
period of revolution of, [312];
rotation of, [308];
satellites of, [559];
satellites, discovery by Herschel, [308];
satellites, movement nearly circular, [309];
satellites, periodical movements, [309];
satellites, plane of orbits, [309], [310];
size of compared with the Earth, [308];
and with other planets, [119];
subject to another attraction besides the Sun, [314]
Ursa major (see [Great Bear])
V
Variable Stars, [429]
Vega, [414], [423], [424], [479];
Struve's measurement of, [442]
Velocity, of light, [261], [262], [265];
of light, laws dependent upon, [511];
of planets, [140–143], [146], [237];
of stars, values of, [483–4]
Venus, ancient study of, [6];
aspects of, [171];
atmosphere of, [189];
brilliancy of, [168];
density of, [558];
diameter of, [191], [558];
distance of, from the Sun, [191], [558];
habitability of, [173];
movement of, [168];
neighbour to the Earth, [109];
orbit of, [114], [135];
orbit form of, [139], [191];
periodic time of, [558];
a planet or "wanderer," [111];
rotation of, [191];
shape of, [169];
size of, compared with other planets, [116], [169];
surface of, [171];
transit of, [152], [176–190];
transit, importance of, [173];
transit predicted by Kepler, [163];
velocity and periodic time of, [142], [143], [191];
view of the ancients about, [157]
Vesta, [233], [238]
Victoria, [242]
Vienna telescope, [14–16]
Virgo, [423]
Vogel and Algol, [485];
and Spica, [486], [487];
and the spectra of the stars, [479], [483]
Volcanic origin of meteorites, [400];

outbreaks on the Earth, [197]
Von Asten and Encke's comet, [349], [350];
and the distance of the Sun, [351];
and the weight of Mercury, [166]
Vortex rings, [469]
Vulcan, [152], [153];
and the Sun, [3]
W
Wargentin, [90]
Watson, Professor, and Mercury, [154]
Watson, Sir William, friendship with Herschel, [302]
Wave-lengths, [60]
Weather, not affected by the Moon, [82]
Wilson, Mr. W.E., and the nebula in Orion, [469]
Witt, Herr G., and Eros, [236]
Wold Cottage meteorite, the, [392]
Wright, Thomas, and the Milky Way, [474]
Y
"Year of Stars," the, [377]
Yerkes Observatory, Chicago, [16]
Young, Professor, account of a marvellous Sun-prominence, [42];
and Sun-spots, [38];
observations on magnetic storms, [39]
Z
Zeeman, Dr., and spectral lines, [491]
Zinc in the Sun, [50]
Zodiac, the, [5]
Zodiacal light, [67]
Zone of minor planets, [234]

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