642 INDEX
Mutual gravitation, 81–82
mv.See Apparent visual magnitude
Mysterium Cosmographicum (Kepler), 64
N
Nadir, 17
Nanometer, 100
Natural law, 66
Natural motion, 77
Natural selection, 586
Neap tides, 87 , 88
Near-Earth Objects (NEOs), 562 –563
Nebulae, 168
disk-shaped, 510
ISM and, 168–169, 170–171
Orion nebula and, 169, 170–171
planetary, 172, 174–175
solar, 399, 407–414, 503
Nebular hypothesis, 398 –399
NEOs. See Near-Earth Objects
Neptune
atmosphere of, 539–540
discovery of, 539
history of, 543
interior of, 541
Jupiter/Saturn compared with, 533, 535
life regarding, 593
moons of, 533, 536, 542–543
plutinos and, 548
profi le of, 540
rings of, 533–534, 535, 536, 541
Rosalind and, 533
rotation of, 412
shepherd moons and, 533, 536
temperature of, 533
Umbriel/Ariel and, 537
Nereid, 542
Neutrino, 151
Neutrino counting, 153–154
Neutron, 123 , 124
Neutron star, 173
New Astronomy (Kepler), 64
Newgrange, 50, 51
Newton, Isaac
birth date regarding, 76
fi rst motion law of, 79
Kepler’s laws and, 83, 86–87
legacy of, 88–90
mutual gravitation and, 81–82
Principia of, 88–89
second motion law of, 79–80
third motion law of, 80
Newtonian focus, 108, 110
Noachian period, 487 –488
Nodes, 43 –44
North celestial pole, 17
Northern lowlands, Mars, 481–482
North point, 17
Nuclear fi ssion, 150
Nuclear fusion, 150
energy transport and, 152–153
hydrogen, 151–152
misconception about, 152
neutrino counting and, 153–154
sun, 150–154
Nucleus, 123
of comets, 566–570O
Oberon, 536
Objective lens, 101 , 102–103
Objective mirror, 101– 102 , 103
Oblateness, 497
Earth, 428
Jupiter, 496
Mars, 477
Mercury, 455
Neptune, 540
Saturn, 511
Uranus, 529
Venus, 465
Occultation, 533, 534
Oort, Jan, 571
Oort cloud, 571 –572
Open orbit, 82, 85
Orbit
closed/open, 82, 85
coorbital satellites and, 520–521
Earth and, 4, 20, 26, 82, 84–85, 139,
428
electron, 124–125
escape velocity and, 83
gravity and, 82, 84–87
Io, 496, 497
Jupiter, 496
Kepler’s laws and, 83, 86–87
Mars, 477
Mercury and, 4, 455
meteors, 556–558
moon, 443
Neptune, 540
permitted, 124–125
planets and, 401
Saturn, 511
Uranus, 529
velocity and, 82–83
Venus, 465
Orcus, 547
Origins
galaxies’, 177–180
matter, 182–185
Milky Way, 176–177star birth, 168–169, 170–171
star death, 172–176
universe, 180–182
Orion nebula
Bok globules and, 169, 170
dust/gas disks in, 169, 171
O star within, 169
star formation in, 169, 170–171
Outfl ow channels, 483
Outgasing, 411
Ovoids, 537 –538
Ozone, 436, 438–439
Ozone layer, 436P
Pallas, 559
Paradigm, 61
Parallax, 55, 56
Herschel, William, measuring, 527
Partial lunar eclipse, 36 –37
Partial solar eclipse, 38
Particles. See also Atom(s)
light as, 100
Paschen spectral lines, 130, 133
Passing star hypothesis, 398
Path of totality, 39
Payne-Gaposchkin, Cecilia, 136–137
Penumbra, 33
Penumbral lunar eclipse, 37
Perigee, 39
Perihelion, 24
Permitted orbits, 124 –125
Perspectives
galaxies’ origins, 177–180
matter origins, 182–185
Milky Way origins, 176–177
star birth origins, 168–169, 170–171
star death origins, 172–176
universe origins, 180–182
Philolaus, 53
Philosophiae Naturalis Principia Mathemati-
ca (Newton), 88–89
Phobos, 489–490
Phoebe, 519, 522
Photon, 100
atom excitation and, 126–127
blackbody radiation and, 127–129
Photosphere, 41 , 42
absorption spectrum, 144
density of, 143–144
granulation, 144–145
limb darkening, 145
sun, 143–145, 147
temperature, 147
thinness of, 143
Piazzi, Giuseppe, 559