Klassifikation der Library of Congress [LCC] (USA)QB637.8

animals(226) asteroids(246) astrobiology(30) astrology(96) astrophysics(244) biology(119) black holes(33) children(601) children's(767) children's literature(121) climate(73) cosmology(436) cosmos(62) Creation(86) early reader(109) earth(1,686) easy reader(122) ecology(91) education(107) educational(83) elementary(131) environment(227) exploration(220) fall(916) galaxies(74) galaxy(51) general science(80) geography(339) geology(594) Grade 2(109) gravity(63) green(63) history(914) history of science(299) hst(31) informational(645) informative(45) Jupiter(201) juvenile(244) juvenile literature(74) juvenile non-fiction(173) kids(207) leaves(204) light(65) lunar(65) Mars(1,026) Mars (Planet)(65) meteorite(15) meteors(183) moon(1,714) nasa(334) natural science(128) natural world(40) nature(959) observation(29) outer space(784) photographs(262) photography(453) picture book(1,614) planet(199) planetology(27) planets(3,553) Pluto(240) popular science(277) preschool(73) primary(89) pseudoscience(48) reader(76) reference(509) rockets(37) school(150) science(13,768) science and technology(63) science fiction(390) science nonfiction(137) snow(127) solar system(3,835) space exploration(600) space flight(139) spacecraft(40) spring(603) Star Trek(353) stars(617) summer(358) time(69) universe(350) volcanoes(101) weather(981) winter(743)