Editing 4 Vesta (section)

==History==

===Discovery===
{{stack|[[File:Ceres and Vesta, Moon size comparison.jpg|alt=|thumb|Vesta, [[Ceres (dwarf planet)|Ceres]], and the [[Moon]] with sizes shown to scale]]}}
[[Heinrich Olbers]] discovered [[2 Pallas|Pallas]] in 1802, the year after the discovery of [[Ceres (dwarf planet)|Ceres]].  He proposed that the two objects were the remnants of a [[Phaeton (hypothetical planet)|destroyed planet]].  He sent a letter with his proposal to the British astronomer [[William Herschel]], suggesting that a search near the locations where the orbits of Ceres and Pallas intersected might reveal more fragments. These orbital intersections were located in the [[constellation]]s of [[Cetus]] and [[Virgo (constellation)|Virgo]].<ref name="Littmann2004"/>  Olbers commenced his search in 1802, and on 29 March 1807 he discovered Vesta in the constellation Virgo—a coincidence, because Ceres, Pallas, and Vesta are not fragments of a larger body.  Because the asteroid [[3 Juno|Juno]] had been discovered in 1804, this made Vesta the fourth object to be identified in the region that is now known as the [[asteroid belt]].  The discovery was announced in a letter addressed to German astronomer [[Johann Hieronymus Schröter|Johann H. Schröter]] dated 31 March.<ref name="Lynn1907"/>  Because Olbers already had credit for discovering a planet (Pallas; at the time, the asteroids were considered to be planets), he gave the honor of naming his new discovery to German mathematician [[Carl Friedrich Gauss]], whose orbital calculations had enabled astronomers to confirm the existence of Ceres, the first asteroid, and who had computed the orbit of the new planet in the remarkably short time of 10 hours.<ref name="Dunnington2004"/><ref name="Rao2003"/>  Gauss decided on the [[Roman mythology|Roman]] virgin goddess of home and hearth, [[Vesta (mythology)|Vesta]].<ref name="MPDictionary"/>

===Name and symbol===
Vesta was the fourth asteroid to be discovered, hence the number&nbsp;4 in its formal designation. The name ''Vesta'', or national variants thereof, is in international use with two exceptions: [[Greece]] and China. In [[Modern Greek|Greek]], the name adopted was the Hellenic equivalent of Vesta, [[Hestia]] {{nobr|({{lang|el|4 {{math|Εστία}}}});}} in English, that name is used for {{nobr|[[46 Hestia]]}} (Greeks use the name "Hestia" for both, with the minor-planet numbers used for disambiguation). In [[Standard Chinese|Chinese]], Vesta is called the 'hearth-god(dess) star', {{lang|zh|灶神星}} ''{{Transliteration|zh|Zàoshénxīng}}'', naming the asteroid for Vesta's role, similar to the Chinese names of [[Uranus]], [[Neptune]], and [[Pluto]].{{efn| {{lang|zh|維斯塔}} ''wéisītǎ'' is the closest Chinese approximation of the Latin pronunciation ''westa''.}}

Upon its discovery, Vesta was, like Ceres, Pallas, and Juno before it, classified as a planet and given a [[Astronomical symbols|planetary symbol]]. The symbol represented the altar of Vesta with its [[Sacred fire of Vesta|sacred fire]] and was designed by Gauss.<ref name=mcbeh-v15/><ref name="effemeridi-1809"/> In Gauss's conception, now obsolete, this was drawn {{nobr|[[File:Vesta symbol (original, fixed width).svg|x20px|Gauss's version of the astronomical symbol for Vesta]]}}. His form is in the pipeline for [[Unicode]] 17.0 as U+1F777 {{math|🝷}}.<ref name=astunicode>{{cite report |last1=Bala |first1=Gavin Jared |last2=Miller |first2=Kirk |date=18 September 2023 |title=Unicode request for historical asteroid symbols |via=unicode.org |publisher=[[Unicode Consortium]] |url=https://www.unicode.org/L2/L2023/23207-historical-asteroids.pdf |access-date=26 September 2023 }}</ref><ref name=pipeline>{{cite web |title=Proposed new characters |series=The Pipeline |date= |website=unicode.org |publisher=[[Unicode Consortium]] |url=https://unicode.org/alloc/Pipeline.html |access-date=6 November 2023 }}</ref>{{efn|
Some sources contemporaneous to Gauss invented more elaborate forms, such as [[File:Vesta symbol (old elaborate).svg|x20px|Temple form of the astronomical symbol for Vesta]] and [[File:Vesta symbol (old elaborate 2).svg|x20px|Elaborate form of the astronomical symbol for Vesta]].<ref name=annuaire-1808/><ref name=Canovai1810/> A simplification of the latter from {{circa|1930}}, [[File:Vesta symbol (Koch, fixed width).svg|x20px|Koch's simplification of the symbol for Vesta]],<ref>{{cite book |first=Rudolf |last=Koch |orig-year=1930 |year=1955 |title=The Book of Signs |publisher=Dover |edition=reprint }}</ref> never caught on.
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The asteroid symbols were gradually retired from astronomical use after 1852, but the symbols for the first four asteroids were resurrected for astrology in the 1970s. The abbreviated modern astrological variant of the Vesta symbol is {{nobr|[[File:Vesta symbol (fixed width).svg|x20px|Astrological version of the astronomical symbol for Vesta]] (U+26B6 {{math|⚶}})}}.<ref name=astunicode/>{{efn|
This symbol can be seen in the top of the most elaborate of the earlier forms, [[File:Vesta symbol (old elaborate 2).svg|x20px|Elaborate form of the astronomical symbol for Vesta]]. It dates from 1973, at the beginning of astrological interest in asteroids.<ref>{{cite book |first=Eleanor |last=Bach |year=1973 |title=Ephemerides of the asteroids: Ceres, Pallas, Juno, Vesta, 1900–2000 |publisher=Celestial Communications |bibcode=1973eacp.book.....B }}</ref>
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After the discovery of Vesta, no further objects were discovered for 38&nbsp;years, and during this time the Solar System was thought to have eleven planets.<ref name=18planets/> However, in 1845, new asteroids started being discovered at a rapid pace, and by 1851 there were fifteen, each with its own symbol, in addition to the eight major planets ([[Neptune]] had been discovered in 1846). It soon became clear that it would be impractical to continue inventing new planetary symbols indefinitely, and some of the existing ones proved difficult to draw quickly. That year, the problem was addressed by [[Benjamin Apthorp Gould]], who suggested numbering asteroids in their order of discovery, and placing this number in a disk (circle) as the generic symbol of an asteroid. Thus, the fourth asteroid, Vesta, acquired the generic symbol {{big|④}}. This was soon coupled with the name into an official number–name designation, {{nobr|''{{big|④}} Vesta'',}} as the number of minor planets increased. By 1858, the circle had been simplified to parentheses, {{nobr|''(4) Vesta'',}} which were easier to typeset. Other punctuation, such as {{nobr|''4) Vesta''}} and {{nobr|''4, Vesta'',}} was also briefly used, but had more or less completely died out by 1949.<ref name=WhenbecameMPs/>

===Early measurements===
{{stack|[[File:New SPHERE view of Vesta.jpg|thumb|[[Spectro-Polarimetric High-Contrast Exoplanet Research|SPHERE]] image is shown on the left, with a synthetic view derived from ''Dawn'' images shown on the right for comparison.<ref>{{cite web |title=New SPHERE view of Vesta |url=https://www.eso.org/public/images/potw1826a/ |website=www.eso.org |access-date=25 June 2018}}</ref>]]}}

Photometric observations of Vesta were made at the [[Harvard College Observatory]] in 1880–1882 and at the [[Observatoire de Toulouse]] in 1909. These and other observations allowed the rotation rate of Vesta to be determined by the 1950s. However, the early estimates of the rotation rate came into question because the [[light curve]] included variations in both shape and [[albedo]].<ref name="McFadden2008"/>

Early estimates of the diameter of Vesta ranged from {{convert|383|km|0}} in 1825, to {{convert|444|km|0|abbr=on}}. [[Edward Charles Pickering|E.C. Pickering]] produced an estimated diameter of {{convert|513|±|17|km|abbr=on}} in 1879, which is close to the modern value for the mean diameter, but the subsequent estimates ranged from a low of {{convert|390|km|0|abbr=on}} up to a high of {{convert|602|km|0|abbr=on}} during the next century. The measured estimates were based on [[photometry (astronomy)|photometry]]. In 1989, [[speckle interferometry]] was used to measure a dimension that varied between {{convert|498|and|548|km|0|abbr=on}} during the rotational period.<ref name="Hughes1994"/> In 1991, an [[occultation]] of the star [[SAO 93228]] by Vesta was observed from multiple locations in the eastern United States and Canada. Based on observations from 14 different sites, the best fit to the data was an elliptical profile with dimensions of about {{convert|550|×|462|km|0|abbr=on}}.<ref name="Povenmire2001"/> ''[[Dawn (spacecraft)|Dawn]]'' confirmed this measurement.{{efn|name=vesta_measurement|The data returned will include, for both asteroids, full surface imagery, full surface spectrometric mapping, elemental abundances, topographic profiles, gravity fields, and mapping of remnant magnetism, if any.<ref name="nssdca 2007_043a"/>}} These measurements will help determine the thermal history, size of the core, role of water in asteroid evolution and what meteorites found on Earth come from these bodies, with the ultimate goal of understanding the conditions and processes present at the solar system's earliest epoch and the role of water content and size in planetary evolution.<ref name="nssdca 2007_043a"/>

Vesta became the first asteroid to have its mass determined. Every 18 years, the asteroid [[197 Arete]] approaches within {{val|0.04|ul=AU}} of Vesta. In 1966, based upon observations of Vesta's [[gravitational perturbation]]s of Arete, Hans G. Hertz estimated the mass of Vesta at {{val|1.20|0.08|e=-10|u=M<sub>☉</sub>}} ([[solar mass]]es).<ref name="science160_3825"/> More refined estimates followed, and in 2001 the perturbations of [[17 Thetis]] were used to calculate the mass of Vesta to be {{val|1.31|0.02|e=-10|u=M<sub>☉</sub>}}.<ref name="aaa430"/> ''Dawn'' determined it to be {{val|1.3029|e=-10|u=M<sub>☉</sub>}}.