Jump to content

Astronomical symbols: Difference between revisions

From Wikipedia, the free encyclopedia
Content deleted Content added
→‎Symbols for dwarf planets and asteroids: +symbols for Egeria & Astraea
→‎Symbols for Sun, Moon, and planets: +obsolete LV symbol for Neptune, also copied some text from Uranus article to here
Line 47: Line 47:
}}</ref> A diagram in Johannes Kamateros' 12th century ''Compendium of Astrology'' shows the Sun represented by the circle with a ray, Jupiter by the letter ''zeta'' (the initial of [[Zeus]], Jupiter's counterpart in [[Greek mythology]]), and the remaining classical planets by symbols resembling the modern ones.<ref name=maunder /> By the 16th century, the symbols had become standardized.<ref name=maunder />
}}</ref> A diagram in Johannes Kamateros' 12th century ''Compendium of Astrology'' shows the Sun represented by the circle with a ray, Jupiter by the letter ''zeta'' (the initial of [[Zeus]], Jupiter's counterpart in [[Greek mythology]]), and the remaining classical planets by symbols resembling the modern ones.<ref name=maunder /> By the 16th century, the symbols had become standardized.<ref name=maunder />


Symbols were created for Uranus and Neptune shortly after their discovery. For Uranus, two variant symbols are seen. One symbol, [[Image:Uranus symbol.svg|15px|Uranus]], invented by [[Johann Gottfried Koehler|J. G. Köhler]] and refined by [[Johann Elert Bode|Bode]], was intended to represent the newly discovered metal [[platinum]]; since platinum was the hardest and most dense metal then known, the symbol for platinum combines the alchemical symbols for [[iron]], ♂, and [[gold]], ☉.<ref name=bode-uranus>{{cite book
Symbols were created for Uranus and Neptune shortly after their discovery. For Uranus, two variant symbols are seen. One symbol, [[Image:Uranus symbol.svg|15px|Uranus]], invented by [[Johann Gottfried Koehler|J. G. Köhler]] and refined by [[Johann Elert Bode|Bode]], was intended to represent the newly discovered metal [[platinum]]; since platinum, commonly called white gold, was found by chemists mixed with iron, and since it was the hardest and heaviest metal then known, the symbol for platinum combines the alchemical symbols for [[iron]], ♂, and [[gold]], ☉.<ref name=bode-uranus>{{cite book
| title = Von dem neu entdeckten Planeten
| title = Von dem neu entdeckten Planeten
| url = http://books.google.com/books?id=ZqA5AAAAcAAJ&pg=PA95
| url = http://books.google.com/books?id=ZqA5AAAAcAAJ&pg=PA95
Line 62: Line 62:
| year = 1850
| year = 1850
| page = 5
| page = 5
}}</ref> Another symbol, [[Image:Uranus's astrological symbol.svg|15px|Uranus]], was based on the letter ''H'' (for Herschel, the discoverer of Uranus).<ref name=gould-uranus /> After Neptune was discovered, the Bureau des Longitudes proposed the name Neptune and the familiar trident for the planet's symbol.<ref name=gould-neptune>{{cite book
}}</ref> Another symbol, [[Image:Uranus's astrological symbol.svg|15px|Uranus]], was suggested by Lalande in 1784. In a letter to Herschel, Lalande described it as "un globe surmonté par la première lettre de votre nom" ("a globe surmounted by the first letter of your name").<ref name=Francisca>{{cite web|title=The meaning of the symbol H+o for the planet Uranus|author=Francisca Herschel|year=1917|work=The Observatory|url=http://adsabs.harvard.edu/abs/1917Obs....40..306H|accessdate=2007-08-05}}</ref>

After Neptune was discovered, the Bureau des Longitudes proposed the name Neptune and the familiar trident for the planet's symbol.<ref name=gould-neptune>{{cite book
| title = Report on the history of the discovery of Neptune
| title = Report on the history of the discovery of Neptune
| url = http://books.google.com/books?id=uyANAQAAIAAJ&pg=PA22
| url = http://books.google.com/books?id=uyANAQAAIAAJ&pg=PA22
Line 70: Line 72:
| year = 1850
| year = 1850
| page = 22
| page = 22
}}</ref>
}}</ref>


The [[International Astronomical Union]] discourages the use of these symbols in journal articles; however, the IAU Style Manual permits certain one- and (to disambiguate Mercury and Mars) two-letter abbreviations for the names of the planets for use in certain contexts, such as in the headings of tables. <ref name=iau-style-manual >{{cite book
The [[International Astronomical Union]] discourages the use of these symbols in journal articles; however, the IAU Style Manual permits certain one- and (to disambiguate Mercury and Mars) two-letter abbreviations for the names of the planets for use in certain contexts, such as in the headings of tables. <ref name=iau-style-manual >{{cite book
Line 211: Line 213:
| #9797;
| #9797;
| <font size="6">♅</font>
| <font size="6">♅</font>
| "H" from the discoverer's last name ([[Sir William Herschel|Herschel]])<ref name=high-school-astronomy />
| a globe surmounted by the letter ''H'' (for [[Sir William Herschel|Herschel]])<ref name=Francisca />
|- align=center
|- align=center
|[[Neptune]]||[[Image:Neptune symbol.svg|25px|Neptune]]<ref name=nasa /><ref name=cox /><ref name=putnam />
|rowspan="2"|[[Neptune]]||[[Image:Neptune symbol.svg|25px|Neptune]]<ref name=nasa /><ref name=cox /><ref name=putnam />
| #9798;
| #9798;
| <font size="6">♆</font>
| <font size="6">♆</font>
| [[Neptune (mythology)|Neptune's]] [[trident]]<ref name=nasa />
| [[Neptune (mythology)|Neptune's]] [[trident]]<ref name=nasa />
|- align=center
|[[Image:Neptune symbol alternate.png|25px|Neptune (alternate symbol)]]<ref name=an-25>{{cite journal
| last = Schumacher
| first = H. C.
| year = 1846
| title = Name de Neuen Planeten
| journal = Astronomische Nachrichten
| volume = 25
| pages = p. 81-82
| url = http://books.google.com/books?id=wlc_AAAAcAAJ&pg=PA89
}}</ref>
|
|
| A globe surmounted by the letters LV (for [[Le Verrier]])<ref name=an-25 />
|}
|}



Revision as of 23:14, 11 May 2010

Chinese Celestial symbols on an antique bronze mirror

Astronomical symbols are symbols used to represent various celestial objects, theoretical constructs and observational events in astronomy. These symbols were commonly used by professional and amateur astronomers. While astronomical symbols are still used in almanacs, they have fallen into disuse in published research and texts on astronomy. [1] Many of the symbols are shared with western astrology, which uses multiple variant forms.

Symbols for Sun, Moon, and planets

The commonly accepted symbols for gods associated with the classical planets, including the sun and the moon, are ultimately of ancient origin. Bianchini's planisphere, produced in the 2nd century,[2] shows Greek personifications of planetary gods charged with early versions of the planetary symbols: Mercury has a caduceus; Venus has, attached to her necklace, a cord connected to another necklace; Mars, a spear; Jupiter, a staff; Saturn, a scythe; the Sun, a circlet with rays radiating from it; and the Moon, a headdress with a crescent attached.[3] In papyri of Greek horoscopes, though, only three symbols are found: a circle with one ray for the Sun, a crescent for the Moon, and an ωρ ligature used to abbreviate the words ώρα and ωροσκόπος. [4]

The earliest known written forms of the modern planetary symbols are seen in medieval Byzantine codices.[5] A diagram in Johannes Kamateros' 12th century Compendium of Astrology shows the Sun represented by the circle with a ray, Jupiter by the letter zeta (the initial of Zeus, Jupiter's counterpart in Greek mythology), and the remaining classical planets by symbols resembling the modern ones.[3] By the 16th century, the symbols had become standardized.[3]

Symbols were created for Uranus and Neptune shortly after their discovery. For Uranus, two variant symbols are seen. One symbol, Uranus, invented by J. G. Köhler and refined by Bode, was intended to represent the newly discovered metal platinum; since platinum, commonly called white gold, was found by chemists mixed with iron, and since it was the hardest and heaviest metal then known, the symbol for platinum combines the alchemical symbols for iron, ♂, and gold, ☉.[6][7] Another symbol, Uranus, was suggested by Lalande in 1784. In a letter to Herschel, Lalande described it as "un globe surmonté par la première lettre de votre nom" ("a globe surmounted by the first letter of your name").[8]

After Neptune was discovered, the Bureau des Longitudes proposed the name Neptune and the familiar trident for the planet's symbol.[9]

The International Astronomical Union discourages the use of these symbols in journal articles; however, the IAU Style Manual permits certain one- and (to disambiguate Mercury and Mars) two-letter abbreviations for the names of the planets for use in certain contexts, such as in the headings of tables. [10]

Sun

Name Symbol Unicode Unicode Display Symbol Represents
Sun Sol[11][12][13] #9737; the Sun

Moon

Name Symbol Unicode Unicode Display Symbol Represents
Moon, or first-quarter moon First quarter moon[14][15][16] #9789; an increscent moon
full moon Full Moon[15][16]
Moon, or last-quarter moon Last quarter Moon[15][16] #9790; a decrescent moon
new moon New Moon[15][16]

Planets

Name Symbol Unicode Unicode Display Symbol Represents
Mercury Mercury[11][17][12] #9791; Mercury's winged helmet and caduceus[11], or the caduceus alone[17][14]
Venus Venus[11][17][12] #9792; Venus' hand mirror[11][17][14]
Earth Earth[11][17][12] #8853; globe with equator and a meridian[11][17]
Earth[12][15][14] #9793; globus cruciger[18], or an inverted symbol for Venus[14]
Mars Mars[11][17][12] #9794; Mars' shield and spear[11][17][14]
Jupiter Jupiter[11][17][12] #9795; Jupiter's thunderbolt[14], an eagle[11], or the letter zeta or Z for Zeus, Jupiter's Greek name[11][17]
Saturn Saturn[11][17][12] #9796; Saturn's sickle or scythe[11][17][14]
Uranus Uranus[6][7] platinum[6][7]
Uranus[17][15][16] #9797; a globe surmounted by the letter H (for Herschel)[8]
Neptune Neptune[11][12][16] #9798; Neptune's trident[11]
Neptune (alternate symbol)[19] A globe surmounted by the letters LV (for Le Verrier)[19]

Symbols for dwarf planets and asteroids

Shortly after Giuseppe Piazzi's discovery of Ceres, a group of astronomers ratified the name, proposed by the discoverer, and chose the sickle as a symbol of the planet.[20]

The symbol for 2 Pallas, the spear of Pallas Athena, was invented by Baron Franz Xaver von Zach, and introduced in his Monatliche correspondenz zur beförderung der erd- und himmels-kunde. [21] In a letter to von Zach, discoverer Heinrich Wilhelm Matthäus Olbers (who had named the newly-discovered asteroid) expressed his approval of the proposed symbol, but wished that the handle of the sickle of Ceres had been adorned with a pommel instead of a crossbar, to better differentiate it from the sign of Venus.[21]

Karl Ludwig Harding, who discovered and named 3 Juno, assigned to it the symbol of a scepter topped with a star. [22]

The symbol for 4 Vesta was invented by German mathematician Carl Friedrich Gauss. Dr. Olbers, having previously discovered and named one new planet (as the asteroids were then classified), gave Gauss the honor of naming his newest discovery. Gauss decided to name the planet for the goddess Vesta, and also designed the symbol (Vesta): the altar of the goddess, with the sacred fire burning on it.[23][24] Other contemporaneous sources use a more elaborate symbol (Vesta) instead.[25][26]

The next two asteroids, 5 Astraea and 6 Hebe, were both discovered by Karl Ludwig Hencke. Hencke requested that the symbol for 5 Astraea be an upside-down anchor;[27] however, a pair of balances was sometimes used instead.[13][28] Gauss named 6 Hebe at Hencke's request, and chose a wineglass as the symbol.[29][30]

As more new asteroids were discovered, astronomers continued to assign symbols to them. Thus 7 Iris had for its symbol a rainbow with a star[31]; 8 Flora, a flower[31]; 9 Metis, an eye with a star[32]; 10 Hygiea, an upright snake with a star on its head[33]; 11 Parthenope, a standing fish with a star[33]; for 12 Victoria, a star topped with a branch of laurel [34]; 13 Egeria, a buckler [35]; 14 Irene, a dove carrying an olive branch with a star on its head[36]; 15 Eunomia, a heart topped with a star[37]; 16 Psyche, a butterfly wing with a star[38]; 17 Thetis, a dolphin with a star;[39], 18 Melpomene, a dagger over a star;[40] and 19 Fortuna, a star over Fortuna's wheel.[40]

Johann Franz Encke made a major change in the Berliner Astronomisches Jahrbuch (BAJ, Berlin Astronomical Yearbook) for the year 1854, published in 1851. He introduced encircled numbers instead of symbols, although his numbering began with Astraea, the first four asteroids continuing to be denoted by their traditional symbols. This symbolic innovation was adopted very quickly by the astronomical community. The following year (1852), Astraea's number was bumped up to 5, but Ceres through Vesta would be listed by their numbers only in the 1867 edition. The circle later became a pair of parentheses, and the parentheses sometimes omitted altogether over the next few decades.[13]

A few asteroids were given symbols by their discoverers after the encircled-number notation became widespread. 26 Proserpina,[41] 28 Bellona,[42] 35 Leukothea,[43] and 37 Fides,[44] all discovered by R. Luther, were assigned, respectively, a pomegranate with a star inside; a whip and spear; an antique lighthouse; and a cross. 29 Amphitrite, discovered by Albert Marth, was assigned a shell for its symbol.[45]

Pluto's name and symbol were announced by the discoverers on May 1, 1930. [46] The symbol, a monogram of the letters PL, could be interpreted to stand for Pluto or for Percival Lowell, the astronomer who initiated the Lowell Observatory's search for a planet beyond the orbit of Neptune.[11]

Dwarf Planets

Name Symbol Unicode Unicode Display Symbol Represents
Ceres Ceres[17][15][13] #9907; Handle-down sickle[17]; cf. the handle-up sickle symbol of Saturn
Pluto Pluto[11][12] #9799; PL monogram for Pluto and Percival Lowell[11]

Asteroids

Name Symbol Unicode Unicode Display Symbol Represents
2 Pallas Pallas[21] #9908; a spear[21][28]
3 Juno Juno[22][47] #9909; a scepter topped with a star[22]
Juno[17][48]
4 Vesta Vesta[23] an altar with fire on it[23]
Vesta[13][28][48]
5 Astraea [27][28] an anchor[27]
5 Astraea (alternate symbol)[49] a pair of balances[17][28]
6 Hebe [17][13][28] a wineglass[29]
7 Iris [17][13] a rainbow with a star inside it[31]
8 Flora [13][28] #9880; a flower[31]
9 Metis [17][13][28] an eye with a star above it[32]
10 Hygeia File:10 Hygeia symbol alternate.png[40][33] a serpent with a star[33]
[13][28] #9877; Rod of Asclepius
11 Parthenope [13][33] a fish with a star[33]
File:11 Parthenope alternate.png[49] a harp[28]
12 Victoria [13][28] a star with a branch of laurel[34]
13 Egeria 13 Egeria[40] a buckler [35]
14 Irene 14 Irene[49] a dove carrying an olive-branch in its mouth and a star on its head[36]
15 Eunomia [13][28] a heart with a star on top[37]
16 Psyche 16 Psyche[40] a butterfly's wing and a star[38]
17 Thetis 17 Thetis[39] a dolphin and a star[39]
18 Melpomene 18 Melpomene[40] a dagger over a star[40]
19 Fortuna 19 Fortuna[40] a star over a wheel[40]
26 Proserpina 26 Proserpina[41] a pomegranate with a star inside it[41]
28 Bellona [42] Bellona's whip and spear[42]
29 Amphitrite 29 Amphitrite[50] a shell[45]
35 Leukothea [43] an ancient lighthouse[43]
37 Fides [44] a cross[44]

Symbols for zodiac constellations and signs

Depending on context, a zodiac symbol may denote a constellation, a sign, or a point. Lists of astronomical phenomena published by almanacs sometimes included conjunctions of stars and planets or the Moon; rather than print the full name of the star, a Greek letter and the symbol for the constellation of the star was sometimes used instead.[51][52] In modern academic usage, all the constellations, including the twelve of the zodiac, have dedicated three-letter abbreviations.[53]

In astronomy, a sign was a unit of arc measurement, now obsolete, equal to 30 degrees.[54][55] Each zodiac symbol thus was used to represent a thirty-degree arc of ecliptic longitude.[55]

The zodiac symbols are also sometimes used to represent points on the ecliptic, each symbol representing the "first point" of each sign; thus ♈ is the vernal equinox, ♋ is the summer solstice, etc.[56][57]

Zodiac

Name Sign Symbol Translation Unicode Display Unicode
Aries 0 ram #9800;
Taurus 1 bull #9801;
Gemini 2 twins #9802;
Cancer 3 crab #9803;
Leo 4 lion #9804;
Virgo 5 virgin #9805;
Libra 6 scale #9806;
Scorpius 7 scorpion #9807;
Sagittarius 8 archer #9808;
Capricornus 9 sea-goat #9809;
Aquarius 10 waterbearer #9810;
Pisces 11 fish #9811;

Other Symbols

Symbols for aspects and nodes appear in medieval texts, although medieval and modern usage of the node symbols differ; ☊ formerly stood for the descending node, and ☋ for the ascending node.[4]

In describing the Keplerian elements of an orbit, ☊ is sometimes used to denote the ecliptic longitude of the ascending node, although it is more common to use Ω (capital omega), which was originally a typographical substitute for the old symbol.[58]

Of the symbols for the five Ptolemaic aspects, only the three displayed here—for conjunction, opposition, and quadrature—are used in modern astronomy.[59]

Other Symbols

Name Symbol Unicode Unicode Display Symbol Represents
comet [15] #9732;
ascending node [12][15] #9738;
descending node [12][15] #9739;
conjunction [15][16] #9740;
opposition [15][16] #9741;
quadrature [15][16] #9633;

See also

References

  1. ^ Pasko, Wesley Washington (1894). American dictionary of printing and bookmaking. p. 29.
  2. ^ "Bianchini's planisphere". Florence, Italy: Istituto e Museo di Storia della Scienza (Institute and Museum of the History of Science). Retrieved 2010-03-17.
  3. ^ a b c Maunder, A. S. D. (1934). "The origin of the symbols of the planets". The Observatory. 57: 238–247.
  4. ^ a b Neugebauer, Otto; Van Hoesen, H. B. (1987). Greek Horoscopes. pp. 159, 163.
  5. ^ Neugebauer, Otto (1975). A history of ancient mathematical astronomy. pp. 788–789.
  6. ^ a b c Bode, J. E. (1784). Von dem neu entdeckten Planeten. pp. 95–96.
  7. ^ a b c Report on the history of the discovery of Neptune. Smithsonian institute. 1850. p. 5. {{cite book}}: Unknown parameter |firstname= ignored (help); Unknown parameter |lastname= ignored (help)
  8. ^ a b Francisca Herschel (1917). "The meaning of the symbol H+o for the planet Uranus". The Observatory. Retrieved 2007-08-05.
  9. ^ Report on the history of the discovery of Neptune. Smithsonian institute. 1850. p. 22. {{cite book}}: Unknown parameter |firstname= ignored (help); Unknown parameter |lastname= ignored (help)
  10. ^ The IAU Style Manual (PDF). 1989. p. 27.
  11. ^ a b c d e f g h i j k l m n o p q r s "Planet Symbols". NASA. Retrieved 2010-03-04.
  12. ^ a b c d e f g h i j k l Allen's astrophysical quantities. Springer. 2001. p. 2. {{cite book}}: Unknown parameter |firstname= ignored (help); Unknown parameter |lastname= ignored (help)
  13. ^ a b c d e f g h i j k l m Hilton, James L. "When Did the asteroids Become Minor Planets?". Retrieved 2010-03-05.
  14. ^ a b c d e f g h The Penny cyclopædia of the Society for the Diffusion of Useful Knowledge, Volume 22. C. Knight. 1842. p. 197.
  15. ^ a b c d e f g h i j k l m The Encyclopedia Americana: a library of universal knowledge, Volume 26. Encyclopedia Americana Corp. 1920. pp. 162–163.
  16. ^ a b c d e f g h i The essence of astronomy: things every one should know about the sun, moon, and stars. G.P. Putnam's sons. 1914. p. 197. {{cite book}}: Unknown parameter |firstname= ignored (help); Unknown parameter |lastname= ignored (help)
  17. ^ a b c d e f g h i j k l m n o p q r s t High-School Astronomy. Sheldon & Co., 1872. pp. 32-36.
  18. ^ "Signs of the Planets". Universe Today. 2009-08-06. Retrieved 2010-03-08.
  19. ^ a b Schumacher, H. C. (1846). "Name de Neuen Planeten". Astronomische Nachrichten. 25: p. 81-82. {{cite journal}}: |pages= has extra text (help)
  20. ^ Bode, J. E., ed. (1801). [[1] Berliner astronomisches Jahrbuch führ das Jahr 1804]. pp. 97–98. {{cite book}}: Check |url= value (help)
  21. ^ a b c d von Zach, Franz Xaver (1802). Monatliche correspondenz zur beförderung der erd- und himmels-kunde, Volume 6. pp. 95-96.
  22. ^ a b c von Zach, Franz Xaver (1804). Monatliche correspondenz zur beförderung der erd- und himmels-kunde, Volume 10. p. 471.
  23. ^ a b c von Zach, Franz Xaver (1807). Monatliche correspondenz zur beförderung der erd- und himmels-kunde, Volume 15. p. 507.
  24. ^ Carlini, Francesco (1808). Effemeridi astronomiche di Milano per l'anno 1809.
  25. ^ Bureau des longitudes (1807). Annuaire pour l'an 1808. p. 5.
  26. ^ Canovai, Stanislao; del-Ricco, Gaetano (1810). Elementi di fisica matematica. p. 149.
  27. ^ a b c Bericht über die zur Bekanntmachung geeigneten Verhandlungen der Königl. Preuss. Akademie der Wissenschaften zu Berlin. 1945. p. 406. Der Planet hat mit Einwilligung des Entdeckers den Namen Astraea erhalten, und sein Zeichen wird nach dem Wunsche des Hr. Hencke ein umgekehrter Anker sein.
  28. ^ a b c d e f g h i j k l Dictionary of minor planet names. Springer. 2003. pp. 15–18. {{cite book}}: Unknown parameter |firstname= ignored (help); Unknown parameter |lastname= ignored (help)
  29. ^ a b Wöchentliche Unterhaltungen für Dilettanten und Freunde der Astronomie, Geographie und Witterungskunde. 1847. p. 315.
  30. ^ Steger, Franz (1847). Ergänzungs-conversationslexikon, Volume 3. p. 442. Hofrath Gauß gab auf Hencke's Ansuchen diesem neuen Planetoiden den Namen Hebe mit dem Zeichen (ein Weinglas).
  31. ^ a b c d "Report of the Council to the Twenty-eighth Annual General Meeting". Monthly notices of the Royal Astronomical Society. 8: 82. 1848. The symbol adopted for [Iris] is a semicircle to represent the rainbow, with an interior star and a base line for the horizon....The symbol adopted for [Flora's] designation is the figure of a flower.
  32. ^ a b >"Extract of a Letter from Mr. Graham". Monthly notices of the Royal Astronomical Society. 8: 147. 1848. I trust, therefore, that astronomers will adopt this name [viz. Metis], with an eye and star for symbol.
  33. ^ a b c d e f de Gasparis, Annibale (1850). "Letter to Mr. Hind, from Professor Annibale de Gasparis". Monthly notices of the Royal Astronomical Society. 11: 1. The symbol of Hygeia is a serpent (like a Greek ζ) crowned with a star. That of Parthenope is a fish crowned with a star.
  34. ^ a b Hind (1850). "Letter from Mr. Hind". Monthly notices of the Royal Astronomical Society. 11: 2. I have called the new planet Victoria, for which I have devised, as a symbol, a star and laurel branch, emblematic of the Goddess of Victory.
  35. ^ a b "Correspondance". Comptes rendus des séances de l'Académie des sciences. 32: 224. 1851. M. De Gasparis adresse ses remerciments à l'Académie, qui lui a décerné, dans la séance solennelle du 16 décembre 1850, deux des médailles de la fondation Lalande, pour la découverte des planètes Hygie, Parthénope et Egérie. M. de Gasparis annonce qu'il a choisi, pour symbole de cette dernière planète, la figure d'un bouclier.
  36. ^ a b Hind (1851). "On the Discovery of a Fourth New Planet, at Mr. Bishop's Observatory, Regent's Park". Monthly notices of the Royal Astronomical Society. 11: 171. Sir John Herschel, who kindly undertook the selection of a name for this, the fourteenth member of the ultra-zodiacal group, has suggested Irene as one suitable to the present time, the symbol to be a dove carrying an olive-branch with a star on the head; and since the announcement of this name, I have been gratified in receiving from all quarters the most unqualified expressions of approbation.
  37. ^ a b de Gasparis, Annibale (1851). "Beobachtungen und Elemente der Eunomia". Astronomische Nachrichten: 174. J'ai proposé le nom Eunomia pour la nouvelle planète. Le symbole serait un coeur surmonté d'une étoile.
  38. ^ a b Sonntag, A. (1852). "Elemente und Ephemeride der Psyche". Astronomische Nachrichten. 34: 283. (in a footnote) Herr Professor de Gasparis schreibt mir, in Bezug auf den von ihm März 17 entdeckten neuen Planeten: "J'ai proposé, avec l'approbation de Mr. Hind, le nom de Psyché pour la nouvelle planète, ayant pour symbole une aile de papillon surmontée d'une étoile."
  39. ^ a b c Luther, R. (1852). "Beobachtungen der Thetis auf der Bilker Sternwarte". Astronomische Nachrichten. 34: 243–244. Herr Director Argelander in Bonn, welcher der hiesigen Sternwarte schon seit längerer Zeit seinen Schutz und Beistand zu Theil werden lässt, hat die Entdeckung des April-Planeten zuerst constatirt und mir bei dieser Gelegenheit dasür den Namen Thetis und das Zeichen [symbol pictured] vorgeschlagen, wodurch der der silberfüssigen Göttinn geheiligte Delphin angedeutet wird. Indem ich mich hiermit einverstanden erkläre, ersuche ich die sämmtlichen Herren Astronomen, diesen Namen und dieses Zeichen annehmen und beibehalten zu wollen.
  40. ^ a b c d e f g h i Hind, J. R. (1852). An astronomical vocabulary. pp. v.
  41. ^ a b c Luther, R. (1853). "Beobachtungen des neuesten Planeten auf der Bilker Sternwarte". Astronomische Nachrichten. 36: 349–350.
  42. ^ a b c Encke, J. F. (1854). "Beobachtung der Bellona, nebst Nachrichten über die Bilker Sternwarte". Astronomische Nachrichten. 38: 143. doi:10.1002/asna.18540380907.
  43. ^ a b c Rümker, G. (1855). "Name und Zeichen des von Herrn R. Luther zu Bilk am 19. April entdeckten Planeten". Astronomische Nachrichten. 40: 373. doi:10.1002/asna.18550402405.
  44. ^ a b c Luther, R. (1856). "Schreiben des Herrn Dr. R. Luther, Directors der Sternwarte zu Bilk, an den Herausgeber". Astronomische Nachrichten. 42: 107. doi:10.1002/asna.18550420705.
  45. ^ a b Marth, A. (1854). "Elemente und Ephemeride des Marz 1 in London entdeckten Planeten Amphitrite". Astronomische Nachrichten. 38: 167.
  46. ^ A handbook of descriptive astronomy. Clarendon Press. 1877. pp. 920–921. {{cite book}}: Unknown parameter |firstname= ignored (help); Unknown parameter |lastname= ignored (help)
  47. ^ a b Letters on astronomy. Harper. 1855. p. 288. {{cite book}}: Unknown parameter |firstname= ignored (help); Unknown parameter |lastname= ignored (help)
  48. ^ a b c Wilson, John (1899). A treatise on English punctuation. p. 302.
  49. ^ Webster's Complete Dictionary of the English Language. 1884. p. 1780.
  50. ^ The Nautical Almanac and Astronomical Ephemeris for the Year 1833. 1831. p. 1.
  51. ^ The American Almanac and Repository of Useful Knowledge, for the Year 1835. 1834. p. 47.
  52. ^ The IAU Style Manual (PDF). 1989. p. 34.
  53. ^ Encyclopædia Britannica, Edition 6. Vol. 3. 1823. p. 155. ...observe, that 60 seconds make a minute, 60 minutes make a degree, 30 degrees make a sign, and 12 signs make a circle.
  54. ^ a b Joyce, Jeremiah (1866). Scientific dialogues for the instruction and entertainment of young people. p. 109.
  55. ^ Roy, Archie E.; David, Clarke (2003). Astronomy: principles and practice. p. 73.
  56. ^ King-Hele, Desmond (1992). A tapestry of orbits. p. 16.
  57. ^ Covington, Michael A. (2002). Celestial objects for modern telescopes, volume 2. pp. 77–78.
  58. ^ Ridpath, John Clark, ed. (1897). The standard American encyclopedia, volume 1. p. 198.