The Story of Astronomy
Page 26
ion An atom becomes an ion when it loses one or more valence ELECTRONS and thus acquires a positive charge, or gains one or more electrons and thus acquires a negative charge.
kelvin (K) Temperatures measured from absolute zero and referred to in units of kelvin, after Lord Kelvin (1824–1907).
Kuiper Belt A ring of space beyond the planets that is the birthplace of COMETS in the SOLAR SYSTEM.
lenticular galaxy A disc-shaped galaxy, but without the spiral arms.
light year The distance traveled by light in a year. About 5.88×1012 miles (9.46×1012 km).
local group The MILKY WAY and its neighboring galaxies.
magnitude A measure of the brightness of any object in the sky. Plotted on a logarithmic scale with the brighter stars as the lower magnitudes.
main sequence A grouping of stars on the HERTZSPRUNG–RUSSELL DIAGRAM showing the hottest and brightest to the coolest and dimmest stars.
magellenic clouds Two neighboring galaxies seen from the Southern Hemisphere.
mass The mass is the amount of matter in a body. (This tautology was first put forward by Isaac Newton.)
Messier catalog The catalog compiled by Charles Messier (1730–1817) consisting of all the nebulous objects in the sky.
meteor A streak of light seen in the sky when any space debris is vaporized by the Earth’s atmosphere.
meteorite A fragment of space debris that survives the atmosphere to land on Earth.
meteroid A fragment of space debris orbiting the Sun.
microwaves ELECTROMAGNETIC RADIATION with wavelengths of the order 0.001 to 1 meter.
Milky Way The galaxy to which the Sun belongs.
nadir The point of the sky directly below the point of observation. The opposite to a ZENITH.
nebula A cloud of interstellar gas and dust.
neutron An uncharged particle found in the nucleus of an atom.
neutron star A very dense remnant of a collapsed star, consisting almost entirely of NEUTRONS.
nova A new star. Usually a star in a binary system which suddenly emits powerful radiant energy.
nuclear fusion Atomic energy generated by the fusing together of atomic nuclei.
Oort Cloud A hollow spherical shell far out in the SOLAR SYSTEM, mainly populated by comets.
orbit The path of an astronomical object moving round another such object.
parallax The apparent displacement, or difference in the apparent position, of an object, caused by actual change (or difference) of the position of the point of observation. In astronomy there are two kinds of parallax, viz diurnal and annual, the former when a celestial object is observed from opposite points on the Earth’s surface, the latter when observed from opposite points of the Earth’s orbit. The horizontal parallax is the diurnal parallax of a heavenly body seen on the horizon.
parsec A measure of distance based on PARALLAX; 3.26 light years.
perihelion The point of a planet’s or comet’s orbit at which it is nearest to the Sun. Opposite to APHELION.
photon A particle of light.
photosphere The region in the Sun’s atmosphere where most of the visible light originates.
planetary nebula A luminous shell of gas ejected from an old low-mass star.
plasma Hot ionized gas (see ION).
precession (of the equinoxes) The earlier occurrence of the equinoxes in each successive sidereal year, due to the retrograde motion of the equinoctial points along the ecliptic, produced by the slow change of direction in space of the Earth’s axis.
proton A positively charged particle found in the nucleus of an atom.
protoplanetary disc A disc of material surrounding a PROTOSTAR or a new star where planets could be created.
protostar A sphere of gas still growing in mass until it is dense enough to shine and become a star.
pulsar A pulsating radio source emitted from a rotating NEUTRON STAR.
quasar A powerful “quasi-stellar radio source” with a very large REDSHIFT.
radio galaxy A galaxy that emits most of its radiation in the radio part of the SPECTRUM.
radio waves Long wavelength ELECTROMAGNETIC RADIATION, used for radio and TV communication.
radius vector A variable line drawn to a curve from a fixed point as origin: in astronomy the origin is usually at the Sun or a planet round which a satellite revolves.
red dwarf A low-mass star on the main sequence of the H–R DIAGRAM.
red giant A large cool star with a high luminosity.
redshift The shifting of light to longer wavelengths. It can be caused by gravitational fields or by high speeds of recession. The shifting of light to shorter wavelengths is called blueshift.
reflection nebula A dense cloud of gas in interstellar space, illuminated by the light of stars lying behind it.
relativity The theory of time and space in the universe as developed by Albert Einstein.
satellite A body in orbit around a larger astronomical body.
Seyfert galaxy A SPIRAL GALAXY with a bright nucleus and with emission lines in its spectrum.
solar system The system of all the astronomical objects subjected to the Sun’s gravity.
solar wind A flow of PROTONS and ELECTRONS emitted by the Sun.
spectrum The result of passing light through a prism to spread out the various colors. The spreading out of other parts of ELECTROMAGNETIC RADIATION by similar means.
spiral arms Arms of gas, dust and stars associated with SPIRAL GALAXIES.
spiral galaxy A flattened and rotating galaxy with two spiral arms winding out from the nuclear bulge at the center of the galaxy.
star A sphere of gas giving out radiation in the ELECTROMAGNETIC SPECTRUM.
starburst A place where there is an exceptionally high rate of star formation.
stellar wind Equivalent to SOLAR WIND, but applied to any star.
supergiant A star with very high luminosity.
supernova A rare stellar explosion when a star can increase its brightness by a millionfold.
supernova remnant The remnant left over when a SUPERNOVA loses its brightness.
transit The passage of one astronomical body across the face of another, for example the planet Venus on the face of the Sun.
ultraviolet The part of the ELECTROMAGNETIC SPECTRUM beyond the violet end of visible light.
universe The whole of space, consisting of matter, energy and radiation.
visible light The part of the ELECTROMAGNETIC SPECTRUM that can be seen with the naked eye.
white dwarf A stellar remnant that has exhausted all its thermonuclear fuel and can no longer shine.
X-ray radiation High-frequency radiation between the gamma ray spectrum and ULTRAVIOLET light.
X-ray star A NEUTRON STAR in a binary system that emits bursts of X-rays.
zenith The point of the sky directly overhead. The highest point of the celestial sphere viewed from any particular place. The opposite to a NADIR.
zodiac The 12 sections of the sky recognized by astronomers and astrologers. Astrologers lay great store by which planets appear in which signs of the zodiac.
FURTHER READING
Armitage, A., Edmond Halley (Nelson 1966)
Aughton, P., Newton’s Apple (Weidenfeld & Nicolson 2002)
Aughton, P., Transit of Venus (Weidenfeld & Nicolson 2004)
Buttman, G., William Herschel (WVG Stuttgart 1961)
Comins, N.F. and Kaufmann, W.J., Discovering the Universe (W.H. Freeman 2005)
Donahue, W.H. Johannes Kepler’s New Astronomy (Cambridge University Press 1992)
Gribbin, J., In Search of the Big Bang (Heinemann 1986)
Hall, A.S., The Scientific Revolution 1500–1800 (Longman 1954)
Hawking, S., A Brief History of Time (Bantam 1988)
Hawking, S., The Universe in a Nutshell (Transworld 2001)
Hoffmann, B., Einstein (Paladin 1975)
Hogben, L., Science for the Citizen (George Allen 1938)
Longair, M.S., Our Evolving Universe (Cambridge University Press 1996)
Mitton, S., The Cambridge Encyclopaedia of Astronomy (Jonathan Cape 1977)
Moore, P., Watchers of the Stars (Michael Joseph 1974)
Roos, M., Introduction to Cosmology (Wiley 2003)
Sagan, C., Cosmos (Abacus 1980)
Skeat, W.W., Chaucer, the Complete Works (Oxford University Press 1912)
Weinberg, S., The First Three Minutes (André Deutsch 1977)
Westfall, R.S., Never at Rest (Cambridge University Press 1980)
White and Gribbin, Stephen Hawking, A Life in Science (Penguin 1992)
Wolf, A., A History of Science, Technology and Philosophy 2nd edn. (Allen Unwin 1950)
Wright, W.A. (ed.), The Rubaiyat of Omar Khayyam (Macmillan 1973)
INDEX
Abell, George, 351
Abul Wala, 57
Académie des Inscriptions et Belles-Lettres, 147
Académie Royale d’Architecture, 147–8
Académie Royale des Sciences, 147–8, 149–50
active optics, 321
Adams, John Couch, 192–3
adaptive optics, 321
Adelard of Bath, 65–6
al-Birini, 57–8
al-Hakim, Caliph, 59
Al Sufi Abd al-Rahman (Azophi), 56–7
Albategnius, 56, 60, 61
Alexander the Great, 24
Alexandria (Egypt), 24, 36, 37–8, 53
Lighthouse, 35
algebra, 55, 61–2
Alhazen, 58–9
Allen Telescope Array, 274–5
Almagest, 43–9, 67
amateur astronomers: role, 325
Andalusia, 53–4, 65–6
Andromeda Galaxy, 57, 233–4, 237–8
Anglo-Saxon Chronicle, 68
angular measurement: origin of degrees and minutes, 18
Antikythera instrument, 51–2
Apollo missions, 306–7
Apollonius of Perga, 45, 48, 62, 93
Arabian and Persian astronomy, 53–66
arc of the meridian, 159
Archimedes, 98
Aristarchus, 25–31
Aristotle, 24–5, 32, 105–6
Armstrong, Neil, 306–7
Arrest, Heinrich Louis d,’ 193
Arzachel, 59–60
astrolabes, 51–2, 54–5, 60, 70–1, 162
astrology
Arab, 57–8
beginnings, 12
in Renaissance, 72, 73, 82–3, 84, 87, 88, 94–5
astrophotography, 203–5
atmospheric refraction, 34
atomic weapons, 225–6
atoms, 198, 247–58, 265–9
Augustus, Roman emperor, 42
Azophi see Al Sufi Abd al-Rahman
Aztecs, 13–14
B2FH paper, 265–7, 297–8
Babbage, Charles, 188
Babylonians, 18–20
Barberini, Cardinal see Urban VIII, Pope
Barrow, Isaac, 135
Bell, Jocelyn, 261–3
Ben Sabbah, 60–1
Bessel, Friedrich W., 200
Besso, Michele, 211
Betelgeuse, 252–3
Big Bang
and black holes, 302
criticisms, 243, 265–6
Hubble’s contribution, 240–1
origins of theory, 222
overview, 326–39
and singularities, 299
situation, 289
black holes
first suggestion of existence, 155–6
overview, 269–73, 276–9, 298–303
and quasars, 281, 298
supermassive, 352–3
theory universe is contained inside, 287–9
Bohr, Niels, 248–9
Bondi, Hermann, 243, 297
Brahe, Tycho, 81–8, 90, 95, 116, 258
Brown, Michael, 318
brown dwarfs, 349
Bruno, Giordano, 70, 96–7
Brunowski, Johann, 91
Burbidge, Geoffrey, 298
Burbidge, Margaret, 298
Byzantines, 52–3
Caccini, Tommaso, 103
calculus, 133–4, 156–7, 189
tensor calculus, 224
calendars
ancient, 13–14
Arab, 61
Babylonian, 18–20
Chinese, 49–50
Egyptian, 20–1
Gregorian, 41, 56, 73–4
Julian, 41–2
Sumerian, 17–18
Callisto, 314, 315
Cambridge University, 112–14, 129–30, 135, 261–2, 292–3
Camden, William, 110
Canopus, 33–4
carbon: formation, 253, 266–7
Cassini, Gian-Domenico, 151–2, 158
Cassini, Jacques, 159
Cassini, Jean-Dominique, comte de, 160
Cassini de Thury (Cassini III), 159–60
Cassini spacecraft, 312, 316
Cassini division, 158–9
Castelli, Benedetto, 104
Centurion (ship), 173
Cepheid variables, 230–1, 237–8, 341
Ceres, 318
CERN, 333
Chaldeans, 33
Challis, James, 192–3
Chandra Observatory and Telescope, 322, 324
Chandrasekhar, Subrahmanyan, 256, 324
Charles II, king of Great Britain and Ireland, 165
Charon, 318
Chaucer, Geoffrey, 70–1
Cheever, Ezekiel, 114
chemical compounds: notation system, 198
Chinese astronomy, 12, 49–50, 258
Christian IV, king of Denmark, 87
Chwolson, Orest, 223
El Cid, 65
clocks and watches
17th-century manufacture, 111
at Greenwich, 167
radium clocks, 249
regulation by pendulum, 96–7, 99
shipboard, 172–6
CMB (cosmic microwave background), 327–30, 335–6, 339
Colbert, Jean-Baptiste, 147, 151
collimators, 322
Columbus, Christopher, 162
comets
and amateur astronomers, 325
discovered by SOHO, 323
Halley’s, 68–9
Helvelius’ observations, 126–7
Kuiper Belt, 319
mentions in Anglo-Saxon Chronicle, 68
Oort Cloud, 319
Shoemaker-Levy 9, 313, 325
supposed influence on life on Earth, 11, 49
Tempel 1’s contrived collision with spacecraft, 324–5
compasses, 194
Compton Telescope, 322
conic sections, 48, 62, 93
Cook, Captain James, 176–7
Copernicus, Nicolaus influence, 83, 91, 96–7, 104, 116
influences on, 60
overview, 71–80
Cosmic Background Explorer, 329
cosmic microwave background see CMB
cosmological constant, 221–2, 355–6
cosmology
ancient Greek, 23, 25–31, 37, 44–9
Arab, 56
Babylonian, 19–20
Copernican, 71–80
Galileo’s support for Copernican, 104–8
Crab Nebula, 263
Crabtree, William, 95, 116, 118, 119, 121–2
cubic equations, 62
Curtis, Heber, 233–4
Cygnus X-1, 273
Dalton, John, 198
dark energy, 340, 355–7
dark matter, 340, 348–51, 352–3
Darwin, Charles, 201–2
Davy, Sir Humphrey, 196
Dawn Mission probe, 318
Deep Impact spacecraft, 324–5
deferents and epicycles system, 44–5
Deptford, HMS, 174
Desargues, Girard, 149
Descartes, René, 148, 149, 150
Dicke, Robert, 328
Digges, Captain Dudley, 174–5<
br />
dimensions: fourth, 283–6
Din Malik Shah, sultan of Jalal, 61
Discovery space shuttle, 319
Doppler, Christian, 232
Doppler effect, 232
Draper, Henry, 204
Draper, John, 204
dust, 282–3, 346
dwarf planets, 318
E = mc2, 221, 226, 247, 252, 338, 355
Earnshaw, Thomas, 176
Earth
age, 201–3
Arab cosmological theories, 56
Copernican cosmology, 71–80, 104–8
craters, 363
distance from Sun, 152, 177
early cosmological theories, 13, 19–20, 23, 25–31, 37, 44–9
death, 253
escape velocity, 270–1
formation, 358–61
and formation of the Moon, 361–3
measuring, 31–2, 151
orbit, 56, 59
rotation cycles, 40
shape, 159
Easter, calculating date, 74
eclipses, lunar
ancients’ knowledge, 26, 28, 39–40, 44, 47
and longitude calculation, 163
supposed influence on life on Earth, 82
eclipses, solar
ancients’ knowledge, 5–7, 23, 25–6, 37–8, 44, 47
and longitude calculation, 163
mentions in Anglo-Saxon Chronicle, 68
Eddington, Sir Arthur, 220, 223, 252, 341
Egyptian astronomy, 11, 20–1
Einstein, Albert, 136, 209–27, 232
Einstein, Eduard, 211
Einstein, Elsa, 225
Einstein, Hans Albert, 211
Einstein, Mileva, 211
Einstein Cross, 223–4
Einstein Ring, 223
electricity, 194–7
nuclear-generated, 251
electromagnetism, 224, 333, 337
electrons, 248
Electroweak Era, 337
electroweak force, 333, 337
elements
discovery, 198–9
formation, 253, 254, 256–7, 265–9, 297–8
entropy, 298, 299
epicycles see deferents and epicycles system
equinoxes, precession of, 40, 42, 47
equivalence, principle of, 217–21
Eratosthenes, 31–2
Eris, 318
escape velocities, 155–6, 270–1
ether, 206–9
Euclid, 62
Eudoxus, 45
Euler, Leonhard, 157, 176
Europa, 314, 315
EUVE (Extreme Ultraviolet Explorer), 322–3
Evans, Revd. Robert Owen, 325
Evelyn, John, 136–8
event horizons, 271, 277
evolution theory, 201–2
extraterrestrial life, 96–7, 261–3, 274–5, 358, 363–4