Roberts, Mrs. Isaac, 7 S Saidak, 34 Saros, 271 Satellites, 110 Saturn, 156 revolution of, 157 satellites, 162, 165 volume, 158 Saturn's rings, 161 Scarpellini, Madame, 7 Scheiner, 95 Schiaparelli, 139 Secchi, Father, 7 Seven Oxen, 32 Sextuple star, 74 Shepherd's Star, 11 Shooting stars, 193, 194, 196 Sirius, 66, 309 _Solar storms_, 100 flames, 105 system, 65 Somerville, Mrs., 6 Spring constellations, 52 Stars, distances, 62 double, 68, 70 first magnitude, 57 number of, 60 quadruple, 73 second magnitude, 58 shooting, 193, 194 temporary, 77 Stars, triple, 72 variable, 75 weight of, 313 Star cluster in Hercules, 79 in the Centaur, 80 St. Catherine, 3 Summer constellations, 53 Sun, 88 houses of the, 43 measurement of distance, 297 photograph of, 96 rotation, 99 temperature of, 105 total eclipse of, 276 weight, 106 Sun and Earth, comparative sizes of, 93 Sun-spots, 95, 101 telescopic aspect of, 97 T Temporary stars, 77, 78 Three Kings, 49 Total eclipse of the moon, 263 of sun, 276 Triangulation, 288 Triple Star, 72 U Umbra, 95 Universe, 22, 23, 90 Urania, 8, 9 Uranoliths, 201, 204 Uranus, 162 V Variable stars, 75 Vega, 40 Venus, 121, 296 phases of, 124 Vesper, 122 Victor Hugo, 24 W Weighing worlds, 309 Winter constellations, 51 Z Zodiac, constellations of, 46, 47 Zones, 225 FOOTNOTES: [1] The French edition of this book is entitled Astronomy for Women.--TRANSLATOR. [2] 1 kilometer = 0.6214 mile; 100 kilometers may be taken as 62 miles. 1 kilogram is about 2.2 lb.; 5 kilograms = 11 lb.--TRANSLATOR. [3] It is useful to know the letters of the Greek Alphabet. They are easily learned, as follows: [alpha] Alpha [beta] Beta [gamma] Gamma [delta] Delta [epsilon] Epsilon [zeta] Zeta [eta] Eta [theta] Theta [iota] Iota [kappa] Kappa [lambda] Lambda [mu] Mu [nu] Nu [xi] Xi [omicron] Omicron [pi] Pi [rho] Rho [sigma] or [sigma] Sigma [tau] Tau [upsilon] Upsilon [phi] Phi [chi] Chi [psi] Psi [omega] Omega [4] All the stars visible at any hour during the year can easily be found with the help of the author's Planisphere mobile. [5] Let it be remarked in passing that the stars might be much farther off than they are, and invisible to our eyes; the Heavens would then assume the aspect of an absolutely empty space, the moon and planets alone remaining.