Events - Discovery of First Asteroid, Ceres 1 January 1801 - 1 January 2001 About Giuseppe Piazzi Father Giuseppe Piazzi, the discoverer of Ceres On 1st January 1801, in Palermo, the Italian astronomer Giuseppe Piazzi (1746-1826) discovered Ceres, the first and largest asteroid. The discovery of Ceres followed that of the planet Uranus, made in 1781 by the British astronomer William Herschel (1783-1822). Piazzi's discovery confirmed the so-called "Titius-Bode's law", which assumed the existence of a "fifth planet" between the orbit of Mars and Jupiter. Later the German astronomer Johann Olbers discovered other "small planets", which the astronomical community called "asteroids" or "minor bodies of Solar System". Currently, we know over a thousand of these objects, an important subset of which, called NEA (Near Earth Asteroids), has become particularly important as their orbits cross the orbit of our planet, thus creating the risk of an impact on the earth's surface.

ESA - Space for Kids - Our Universe - Asteroids – the minor planets Asteroid 243 Ida and its newly discovered moon, Dactyl Asteroids – the minor planets Asteroids are small, rocky bodies that have been left over from the formation of the planets 4.5 billion years ago. They are often known as 'minor planets'. There are thought to be billions of these chunks of rock. Most of them lie in a doughnut-shaped 'main belt' between the orbits of Mars and Jupiter. On the inner edge of this main belt, asteroids take about three years to orbit the Sun. Those near the outer limit of the main belt take twice as long. The word 'asteroid' means 'star-like'. They were given this name because they can only be seen as points of light in most telescopes. By the early 20th century, astronomers were calling them the 'vermin of the skies'. They were visible in such large numbers that they were spoiling photographs of distant galaxies and nebulas. The largest of the asteroids, Ceres, was the first to be discovered. It was found by Giuseppi Piazzi from Palermo, Sicily, on 1 January 1801.

A second minor planet – Pallas – was found by Wilhelm Olbers in 1802. This was followed by Juno (1804) and Vesta (1807). Since 1847, not a year has passed without the discovery of at least one asteroid. When did the asteroids become minor planets? When did the asteroids become minor planets? by James L. Hilton Sitemap Discovery of the Asteroids The controversy over whether Pluto should be given a minor planet number and possibly be demoted from the ranks of the major planets reminds me of a similar controversy that occurred 150 years ago. This controversy involved whether or not the bodies discovered between Mars and Jupiter should be considered equal to the seven other planets known at that time. Titius von Wittenburg (1766) discovered that the relative distances of the six known planets from the Sun almost fit a simple relation. But it had a problem. It predicted there should be a planet between the orbits of Mars and Jupiter. In 1772 he published a tract proposing that a planet should exist in the gap.

According to Cunningham (1988) , Johann Bode, director of the Berlin Observatory so popularized this tract that the relation is now known as Bode's law. In 1781 Uranus was discovered at just the distance where Bode's Law predicted a seventh planet (including the gap between Mars and Jupiter) should occur. This touched off a search for a planet in the gap between Mars and Jupiter. The search ended, literally before it had begun, on January 1, 1801 when Guiseppe Piazzi at the Palermo Observatory discovered a 'star' that had moved from its position the previous night in the constellation of Taurus (von Zach 1801) . Like Uranus, it was found to be a body at exactly the distance predicted by Bode's Law. Two consecutive successes for a relation that has no known physics behind it. Piazzi named the new planet Ceres Ferdinandea after Ceres, the Roman goddess of the harvest, and King Ferdinand IV of Naples and Sicily. The second half of the name was dropped after several years for political reasons. Thus, the gap was filled and the search ended.

Unexpectedly, on March 28, 1802 Heinrich Olbers discovered another small body while observing Ceres. Its semi-major axis was nearly the same as Ceres, and posed problems for the picture of the solar system that had been emerging over the previous decades. Eventually, this new body was named Pallas. Neither of these bodies fit the conventional idea of a planet because they were so small that their disks were nearly unobservable. Using a projection system Herschel (1802) determined 161.6 miles (260.0 km) for the diameter of Ceres and 147 miles (237 km) for Pallas. These results are nearly a factor of four too small for Ceres and more than a factor of two too small for Pallas. Because of this starlike appearance, Herschel declared, "From this, their asteroidal appearance, if I may use that expression, therefore, I shall take my name, and call them Asteroids; reserving for myself, however, the liberty of changing that name, if another, more expressive of their nature should occur." Thus Herschel argued that Ceres and Pallas were not the same as the other planets.

However, other astronomers of the time thought otherwise. These two new additions to the solar system were listed along with the rest of the planets in order of increasing distance from the Sun. They were also given symbols by their discoverers to be used when recording observations. The symbols for the planets, shown in Table 1, were and are used as a shorthand notation by astronomers, and others. To fulfill this role, they are quick to draw, are easily distinguishable, and do not require much skill to produce. Many of the symbols have several variants. The ones shown in Table 1 are those almost universally adopted by the astronomical community. Table 1. The Symbols of the Sun, Moon, and Planets. Body Pluto Moon The discoveries of Juno in 1804 and Vesta in 1807 raised concern in astronomers of the day that the asteroids were fragments of a planet that had somehow disintegrated. This theory was first proposed by Olbers upon the discovery of Pallas. However, Juno and Vesta were added to the catalog of planets along with Ceres, Pallas, and, in 1846, Neptune.

The acceptance of the first four asteroids was so matter-of-fact that introductory texts such as First Steps to Astronomy and Geography (1828) lists the planets as, "Eleven: Mercury, Venus, the Earth, Mars, Vesta, Juno, Ceres, Pallas, Jupiter, Saturn, and Herschel." Herschel was an alternate name for Uranus (after its discoverer) used in Britain until the 1850's. The Scene Becomes Complicated The fifth asteroid, Astraea was discovered near the end of 1845, nearly 39 years after the discovery of Vesta. The year 1847 saw the discovery of three new asteroids. By the end of 1851 there were 15 asteroids, still listed by distance from the Sun. Fourteen of them each had their own symbol; although, the symbol for Irene had never been drawn, only described (Gould 1852) ! Some of these symbols, in Table 2, were quite fanciful and took significant artistic skill to draw.

Only the symbols for Ceres, Pallas, and Juno kept the same basic simplicity of the symbols for the larger bodies in the solar system. Table 2. The Old Symbols of the Asteroids. From Gould (1852) . Asteroid "A dove carrying an olive-branch, with a star on its head" (Hind 1852) (never drawn) Eunomia Encke (1851) made a major change in the Berliner Astronomisches Jahrbuch, BAJ, for 1854. He said, "Finally, I want to add that - in view of the complications and difficulties with the recently used planetary symbols - I took the liberty to introduce the encircled numbers in stead of symbols," (Translation by Schmaedel, 1999 ). However, there were some very definite differences from today's scheme. The asteroids Encke was referring to began with Astrea which was given the number (1) and went through (11) Eunomia. Ceres, Pallas, Juno, and Vesta continued to be denoted by their traditional symbols.

Not only that, but Ceres through Vesta continued to be listed, in semi-major axis order along with the ephemerides of the major planets while Astrea through Eunomia, and Neptune were relegated to a section at the end of the BAJ. This innovation was immediately seized upon by the astronomical community at large. American astronomer, B.A. Gould (1852) noted: As the number of known asteroids increases, the disadvantages of a symbolic notation analogous to that hitherto in use increase much more rapidly even than the difficulty of selecting appropriate names from the classic mythology. Not only are many of the symbols proposed inefficient in suggesting the name of which they are intended to be an abbreviation; but some of them require for their delineation more artistic accomplishment than an astronomer is necessarily or generally endowed with.

To simplify this system he proposed a new set of symbols: To remedy this evil, and not to lose the unquestionable advantage connected with a system of symbols easily remembered and readily drawn,-it has been agreed upon by several astronomers in Germany, France, England, and America, to propose for adoption a more simple system for the group in question,-consisting of a circle containing the number of the asteroid in the chronological order of its discovery. The new system of symbols was designed to relieve the growing confusion and restore the original intent of the symbols, a quick shorthand way of referring to solar system bodies; not to give the asteroids a different status from the rest of the planets. However, Gould did state, "...we thus have a symbol ready for every asteroid hereafter to be discovered, and this remarkable group are distinguished from the larger planets in the character of their notation." In the BAJ for 1855 (Encke, 1852) the numbering of the minor planets at the back began with (5) Astrea and goes through (15) Eunomia. Ceres through Vesta continued to be listed in semi-major axis order with the major planets, using their old symbols.

This continued until the BAJ for 1867 (Encke, 1864) where they are listed as (1) Ceres, (2) Pallas, (3) Juno, and (4) Vesta in order of discovery along with the other asteroids. The first new asteroid for which the new symbol convention was used was (16) Psyche by Ferguson (1852) in the publication of a series of observations at the U.S. Naval Observatory. However, at least three additional asteroids, (28) Bellona ( Encke, 1854 ), (35) Leukothea ( Rumker & Peters 1855 ), and (37) Fides ( Luther 1855 ), were given the symbols in Table 3. The symbol for Leukothea, the most complicated of all, is described by Rumker & Peters as representing an ancient lighthouse. However, there is no evidence that these symbols were ever used outside of their initial publication in the Astronomische Nachrichten. Table 3. Symbols for the Asteroids Introduced after 1852.

Asteroid (35) Leukothea (37) Fides Cunningham (1988) states that this set of symbols for the asteroids lasted until 1931 when it was replaced by a number followed directly by the name; however, I have not been able to find an official notice of the adoption of the present scheme of numbering asteroids. On the other hand, the literature shows that several different schemes were used during the latter half of the nineteenth century. The present form of number name is first found in the Astronomische Nachrichten (1911) . The Change Occurs The acceptance of the new system of symbols was extremely fast. The Astronomical Journal, edited by Gould, adopted the new symbols immediately. The journal Astronomische Nachrichten had articles sporadically including the new symbols beginning 1854, and adopted them for its index beginning in 1861. The Royal Greenwich Observatory began labeling observations of the asteroids with the new symbols beginning in 1858 with the publication of observations from 1856. The Paris Observatory used them in its table of contents in 1858, with the publication of its first volume of observations. And the U.S.

Naval Observatory adopted the use of the new symbols in 1863 with the publication of its observations from 1852. The two major almanacs that printed asteroid ephemerides at this time had interesting reactions to the introduction of the new symbols. The British The Nautical Almanac and Astronomical Ephemeris had been publishing ephemerides for Ceres, Pallas, Juno, and Vesta in order of their semi-major axes between the ephemerides of Mars and Jupiter. In the volume for 1856, published in 1853, it stopped printing asteroid ephemerides altogether. The BAJ continued to publish the ephemerides of the first four asteroids discovered in semi-major axis order using the old symbols up through the volume for 1866, published in 1864. The ephemerides of the other asteroids were given in numerical order in a section a section at the end of the BAJ along with the ephemeris for Neptune. Beginning in 1852 there was also a table of opposition dates included at the end of the asteroid ephemerides at the end of the BAJ.

This table included the opposition dates for Ceres through Vesta, indicating sort of a 'dual citizenship' for the first four asteroids. Ceres through Vesta were not included with the other asteroids until the edition for 1867, published in 1864. This was the first volume since the introduction of the new symbols not published under the direction of Encke. The BAJ evidently went so far as to announce a policy to refer to the asteroids (60) and higher by their numbers only. This led Förster (1861) to comment, "As for naming planets, Berlin defines them by numbers only from planet (60) onwards," (Translation by Schmaedel, 1999 ). However, the edition for 1864, printed in 1861, and all subsequent of the BAJ refer to all the known asteroids by both number and name. However, the advent of the new symbols also brought with it other changes. Except for the U.S. Naval Observatory, all of the other publications immediately began publishing their observations in order of their numerical symbol rather than their distance from the Sun.

The Paris Observatory also moved the observations of the asteroids to a section separate from the observations of the other planets, while the Royal Greenwich Observatory left the observations, in numerical order, between the observations of Mars and Jupiter. The Asteroids are Called 'Minor Planets' The British The Nautical Almanac and Astronomical Ephemeris had been producing the elements of the asteroids under the heading of 'Minor Planets, Elements of' since its volume for 1845, published in 1841. This is the only instance of the use of the phrase 'minor planet' I have found previous to the introduction of the new symbols for the asteroids. Strangely, this section was dropped from the almanac along with the ephemerides of Ceres, Pallas, Juno, and Vesta in the volume for 1856, published in 1853. The first use of 'Kleine Planeten' after the introduction of the new system of symbols was as 'kleine Planeten' in a paper by Jahn (1854) in Astronomische Nachrichten.

By 1861, the Astronomische Nachrichten uses 'kleine Planete' as a subcategory to Planete (planet) in the index to collect the articles on the asteroids. The Astronomische Nachrichten kept the asteroids as a subcategory of the planets until it published its general index of volumes 181-210 in 1932 ( Astronomische Nachrichten 1932 ). Prior to 1866 the Paris Observatory used the numerical symbols only in the table of contents. That year, the Paris Observatory first uses the description 'petites planetes' in the observations. The asteroids Ceres through Vesta, however, are conspicuously not included in the category of 'petites planetes'. The observation of the first four asteroids are tabulated, in order of discovery, not with the other planets, but in a section immediately before the section titled 'Petites planetes'. Only beginning in 1868 (Paris Observatory 1868) are these four bodies included with the rest of the 'petites planetes'.

Like the BAJ the Paris Observatory evidently gave Ceres through Vesta a sort of 'dual citizenship' until the mid-1860's. The U.S. Naval Observatory used the word 'asteroids' to describe the bodies between the orbits of Mars and Jupiter until 1868. At that time it switched to using the term 'small planets' (U.S. Naval Observatory 1868) . In 1892 it switched back to 'asteroid' (U.S. Naval Observatory 1892) then to 'minor planet' in 1900 (Harkness & Skinner 1900) , and finally back to 'asteroid' in 1929 (Peters 1929) . The U.S. Nautical Almanac Office, an institution independent of the U.S. Naval Observatory in the nineteenth century, generally mirrored the usage of the U.S. Naval Observatory. Aside from a single usage of the term 'minor planet' in 1866, the communications of the U.S.

Nautical Almanac Office always referred to the asteroids as either 'asteroids' or 'planets.' It is also clear that the Office desired to produce a full set of ephemerides during a time in which it was struggling to establish itself and produce its first volumes (Report of the Nautical Almanac Office 1849-1896) . B.A. Gould at The Astronomical Journal never used the term 'minor planet,' always opting for 'asteroid'. However, the asteroids were listed separately from the other planets. Only with the publication of the index to volume 90 in 1985 of the Astronomical Journal ( Astronomical Journal 1985 ), long after Gould's death, was the term 'minor planets' used. In December 1998, the index of volume 116 of the Astronomical Journal uses the puzzling category of 'Minor Planets, Asteroids' ( Astronomical Journal 1998 ). The Royal Greenwich Observatory appears to have held out until after the turn of the century. It continued to publish the observations of the asteroids between the observations of Mars and Jupiter.

However, they are listed in numerical order rather than in order of semi-major axis. The title of the section was 'Observations of the Sun, the Moon, and the Planets'. The Royal Greenwich Observatory never used either the word 'minor' or 'asteroid' in regard to any of its observations of solar system bodies until the publication of its 1905 observations ( Royal Greenwich Observatory 1907 ). Thus, the term 'minor planet' was quickly adopted by the astronomical community. But, its acceptance was not universal. The Sizes of the first three asteroids shrink At the time the description 'minor planet' began to be used, the most widely disseminated values for the diameters of the first four asteroids discovered were Ceres, 2613 km; Pallas, 3380 km; Juno, 2290 km; and Vesta, "not more than 383 km" (Hughes 1994) . The diameters of the first three asteroids were derived from direct estimates of the sizes of their disks by Schroter (1811) and are directly comparable to the 2390 km of Pluto.

The pre-1855 asteroid diameters, shown in Figure 1, are grossly too large. Fig.1. The diameters determined for the four largest asteroids at different times. The diameter of Pluto is included for purposes of comparison. Conversely, the first determination of the diameters of the asteroids after the use of the term minor planets began to be used were too small. Stampfer (1856) produced diameters of 350, 270, 200, and 400 km for Ceres, Pallas, Juno, and Vesta respectively. These diameters were based on photometry rather than trying to measure the angular diameter directly. However, the albedos chosen were more like that of an icy body in the outer solar system rather than a rocky body of the inner solar system which these asteroids more closely resemble. Just as the earlier diameters determinations made as 'planets' were way too large, the first 'minor planet' diameters were way too small. In both cases the size determined depended on the assumptions that went into interpreting the data.

The question that can not be answered is, "How much were these assumptions colored by how the observers thought of the bodies they were observing?" In either case, the assumptions made were not necessarily warranted. Nonsymbolic symbols Finally, the use of the numbers as part of a symbolic shorthand for the asteroid names appears to have lost its symbolism shortly after it was introduced. Here again The Astronomical Journal (1858) led the way. Beginning in 1858 it marked newly discovered asteroids by enclosing their number in parentheses rather than a circle. Once the asteroid's orbit was firmly established, the symbol was then changed to the number enclosed by a circle. This format lasted only until 1888 when it switched to the number followed by the name separated by a comma ( Astronomical Journal 1888 ). Finally, in 1895 it switched back to using parentheses for all asteroids and always followed by the asteroid's name ( Astronomical Journal 1895 ). The U.S. Naval Observatory (1868) adopted the parentheses followed by the name for the asteroids in 1868.

In 1872 it replaced the parentheses with a circle, but kept the name ( U.S. Naval Observatory 1895 ). It used this convention until 1949. At this time only the first four asteroids, Ceres, Pallas, Juno, and Vesta, which it referred to by name only, were observed ( Watts & Adams 1949 ). The Astronomische Nachrichten (1872) started using parentheses followed by the name for all asteroid numbers in 1872. And then switched to the present day format of number and name without circle, parentheses, or comma in 1911 ( Astronomische Nachrichten 1911 ). The Paris Observatory kept the number within a circle symbol right up to 1908, but always gave the name along with the symbol. Cunningham (1988) asserts that the symbol of a number enclosed by a circle was the official designation for asteroids until 1931 when the current nomenclature of the number, sometimes enclosed in parentheses in paper titles and indices, followed by the name without a separating comma was adopted. However, I do not know of any agreement codifying this.

It is also clear that the number name designation had become the de facto standard in the literature by evolution over the 73 years between 1858 and 1931. The number in a circle for an asteroid had quickly lost its nature as a symbol and merely become an accounting tool for the ordering of the asteroids. Conclusions Along with the adoption of a new set of symbols that easily separated the asteroids from the other planets, it appears that the change from planet to minor planet happened very quickly. It was recognized from the beginning that these bodies did not fit along with the rest of the planets, but during the years in which the number of known asteroids was small, they were included on the list of solar system bodies just as if they were regular planets. However, once their numbers grew too large to fit the existing scheme of classification, their uniqueness was quickly recognized and a new class of solar system objects was created. The event that appears to have triggered this reevaluation of the asteroids was the introduction of a new set of symbols to use as a shorthand notation for them. The new set of symbols had nothing to do with judging whether or not the asteroids were planets.

They were designed to restore the reason for having the symbols in the first place, a quick convenient method of referring to a body. Nor is it clear that the name 'minor planet' was meant to separate the asteroids from the other planets. However, the introduction of the new system of symbols had the unintended consequence of reordering the asteroids from the traditional ordering of the planets, by semi-major axis, to numerical order and setting them apart from the other planets. This separation allowed a new category of solar system objects to be recognized. The BAJ and the Paris Observatory accorded Ceres through Vesta a form of 'dual citizenship' with both the planets and the asteroids through the mid-1860's. The failure of this dual categorization is noteworthy because Ceres, the first asteroid discovered, is estimated to contain 30-40% of the mass of the asteroid belt, while Pallas and Vesta combined are nearly as massive as Ceres. Because they fit the mold of a minor planet better than that of a regular planet, even these largest asteroids are considered minor planets after more than 50 years of being accepted as planets like Jupiter, Saturn, and Mercury.

The label of 'minor planet' also appears to have had almost immediate consequences in terms of assumptions made in determining their diameters. Almost immediately after the term 'minor planet' was adopted a new determination of the diameters of the first three asteroid produced values only 10% of those previously adopted, and much smaller than today's accepted values. Although the methods used in the different eras changed radically, they both required that the observer make assumptions in reducing the data. These assumptions may have been colored by how the observers thought of the asteroids. Acknowledgments I would like to acknowledge the works of C.J. Cunningham (1988) and D.W. Hughes (1994) . They were both invaluable in finding starting points for the primary sources on the history of the discovery of the asteroids and their diameters, respectively. I also would like to acknowledge R.A. Kowalski (1999, private communication) whose talk "A Brief History of Minor Planet Research," describes a somewhat different picture than the one I first formed on this subject. References Astron. J. 1858, 5, 193-201. Astron. J.

1888, 7, 193. Astron. J. 1895, 12, 207-213. Astron. J. 1985, 90, 2672. Astron. J. 1998, 116, 3113. Astronomische Nachrichten 1854, Register zu Band, 38, 394. Astronomische Nachrichten 1861, Register zu Band, 54, 394. Astronomische Nachrichten 1872, Register zu Band, 79, 398-401. Astronomische Nachrichten 1911, Register zu Band, 180, 467. Astronomische Nachrichten 1932, General Index to Volumes 181-210, 213-338. Cunningham, C.J. 1988, Introduction to Asteroids, (Willmann-Bell: Richmond, VA). Encke, J.F.

1851, Berliner Astronomisches Jahrbuch for 1854, (Berlin). Encke, J.F. 1854, Astronomische Nachrichten, 38, 143. Ferguson, J. 1852, Astronomische Nachrichten, 35, 51. First Steps to Astronomy and Geography 1828, (Hatchard & Son: Piccadilly, London). Förster, W. 1861, Astronomische Nachrichten, 55, 116. Gould, B.A. 1852, On the Symbolic Notation of the Asteroids, Astron. J., 2, 80. Herschel, W. 1802, Phil. Trans. Royal Society. Harkness, W. & Skinner, A.N. 1900, "Transit circle Observations of the Sun, Moon, Planets, and Miscellaneous Stars 1894–1899," Publications of the U.S. Naval Observatory 2nd Series, vol. 1, 397. Hind, J.R.

1852, From a Letter of Mr. Hind to the Editor, Astron. J., 2, 22-23. Hughes, D.W. 1994, The Historical Unraveling of the Diameters of the First Four Asteroids, Q. J. R. Astr. Soc., 35, 331-344. Jahn, G.A. 1854, "Ueber die gegenseitige Lage der Bahnen der kleine Planeten," Astronomische Nachrichten, 38, 81-84. Luther, R. 1855, Astronomische Nachrichten, 42, 107. Paris Observatory 1858, Annales de l'Observatoire Impérial de Paris Publiées, 1, 381–387. Paris Observatory 1866, Annales de l'Observatoire Impérial de Paris Publiées, 10, 239–244.

Paris Observatory 1868, Annales de l'Observatoire Impérial de Paris Publiées, 19, I44–I52. Peters, G.H. 1929, "Asteroid Observations by Photographic Methods," Publications of the U.S. Naval Observatory 2nd Series, vol. 12, Part 2, 347-526. Various authors (1849–1896), "Report of the Nautical Almanac Office" in Report of the Secretary of the Navy. Royal Greenwich Observatory 1858, Observations for the Year 1856, 27-34. Royal Greenwich Observatory 1907, Observations for the Year 1905 Rumker, G. & Peters, C.A.F. 1855, Astronomische Nachrichten, 40, 373. Schmaedel, L. 1999, Dictionary of Minor Planet Names, 4th ed., (Springer: Berlin). Schroter, J.H.

1811, Lilienthalsche Beobachtungen der neuerentdeckten Planeten Ceres, Pallas, und Juno, zur genauen und richitigen Kenntniss iher 1805 wahren Grossen, Atmospharen, und ubrigen merkwurdigen Naturverhaltnisse im Sonnengebiete, etc. Stampfer, see Bruhns, C.C. 1856, De Planetis Minoribus inter Martem et Jovem circa Solem versantibus, Berlin. Titius von Wittenburg 1766, Betrachtung uber die Natur, vom Herrn Karl Bonnet, p. 7, Leipzig (translation into German from French). U.S. Naval Observatory 1868, Washington Observations for 1866, 401. U.S. Naval Observatory 1892, Washington Observations for 1888, C20. U.S. Naval Observatory 1895, Washington Observations for 1890, pp. 88, 97-99. von Zach, F.

1801, Monthly Correspondence, 3, 602. Watts, C.B. & Adams, A.N. 1949, "Results of Observations made with the Six-Inch Transit circle 1925–1941," Publications of the U.S. Naval Observatory 2nd Series, vol. 16, Part 1, 200-203 . Giuseppe Piazzi | Italian astronomer | Britannica.com Italian astronomer Edmond Halley Giuseppe Piazzi, (born July 16, 1746, Ponte di Valtellina, Lombardy [Italy], Habsburg crown land—died July 22, 1826, Naples), Italian astronomer who discovered (January 1, 1801) and named the first asteroid , or “minor planet,” Ceres . Piazzi became a Theatine priest about 1764 and a professor of theology in Rome in 1779, and in 1780 he was appointed professor of higher mathematics at the Academy of Palermo.

Later, with the aid of the viceroy of Sicily , he founded the Observatory of Palermo . There he produced his great catalog of the positions of 7,646 stars and demonstrated that most stars are in motion relative to the Sun . There also he discovered Ceres and the high proper motion of the important double star 61 Cygni . Learn More in these related articles: astronomy science that encompasses the study of all extraterrestrial objects and phenomena. Until the invention of the telescope and the discovery of the laws of motion and gravity in the 17th century, astronomy was primarily concerned with noting and predicting the positions of the Sun, Moon, and planets,... asteroid any of a host of small bodies, about 1,000 km (600 miles) or less in diameter, that orbit the Sun primarily between the orbits of Mars and Jupiter in a nearly flat ring called the asteroid belt. It is because of their small size and large numbers relative to the major planets that asteroids are... Ceres (dwarf planet) dwarf planet, the largest asteroid in the main asteroid belt, and the first asteroid to be discovered.

Ceres was found, serendipitously, by the Italian astronomer Giuseppe Piazzi of the Palermo Observatory on January 1, 1801. Additional observations of the object by Piazzi were cut short by... 3 References found in Britannica Articles Assorted Reference Corrections? Updates? Help us improve this article! Contact our editors with your feedback. MEDIA FOR: You have successfully emailed this. Error when sending the email. Try again later. Edit Mode Submit Tips For Editing We welcome suggested improvements to any of our articles. You can make it easier for us to review and, hopefully, publish your contribution by keeping a few points in mind. Encyclopædia Britannica articles are written in a neutral objective tone for a general audience. You may find it helpful to search within the site to see how similar or related subjects are covered. Any text you add should be original, not copied from other sources. At the bottom of the article, feel free to list any sources that support your changes, so that we can fully understand their context. (Internet URLs are the best.) Your contribution may be further edited by our staff, and its publication is subject to our final approval.

Unfortunately, our editorial approach may not be able to accommodate all contributions. Submit Thank You for Your Contribution! Our editors will review what you've submitted, and if it meets our criteria, we'll add it to the article. Please note that our editors may make some formatting changes or correct spelling or grammatical errors, and may also contact you if any clarifications are needed. Uh Oh There was a problem with your submission. Please try again later. Close Date Published: May 08, 2015 URL: Access Date: January 18, 2017 Share Giuseppi Piazzi Research Papers on the Man who Discovered Astroids Giuseppe Piazzi Giuseppi Piazzi research papers examine the man who discovered astroids. First discovered by Giuseppe Piazzi in 1801, asteroids , or minor planet, have not been extensively discussed in essays. As such, this essay provides an overview of asteroids including information on how they are classified and which ones are potentially dangerous for the planet earth . By looking at asteroids and their impact on the earth, it is hoped that some insight into the importance of Giuseppe Piazzi essays will be gleaned.

Giuseppe Piazzi was an astronomer born in Ponte di Valtellina in 1746. At the age of 33, Piazzi became Theatine monk and professor of theology in Rome. By 1780, Piazzi had become a professor of mathematics at the Academy of Palermo and in 1789 he set up an observatory at Palermo. Interestingly, when Piazzi observed the first asteroid on the first day in January 1801, he thought he had discovered a comet. However, after observing the object and plotting its orbit, Piazzi came to realize that the object he once believed to be a comet behaved more like a small planet. Because Piazzi came to the conclusion that the object he observed in the sky was indeed a planet, he named the object Ceres, after the Sicilian goddess of grain. Shortly after the discovery of Ceres, Pallas, Vesta and Juno were discovered and by the end of the nineteenth century , astronomers had discovered more than several hundred “planets.” Each year, thousands of asteroids are discovered; today there are more several thousand asteroids that have given provisional designations.

While many science term papers and essays speculate that there are many thousands more that cannot be viewed from earth, scientists speculate that there are more than a million asteroids in our solar system. Related Research Paper Topics Giuseppe Piazzi discovers the dwarf planet Ceres | History of Modern Humanity | Builtvisible Read more... Giuseppe Piazzi discovers the dwarf planet Ceres Ceres (/ˈsɪəriːz/; minor-planet designation: 1 Ceres) is the largest object in the asteroid belt, which lies between the orbits of Mars and Jupiter. Its diameter is approximately 945 kilometers (587 miles), making it the largest of the minor planets within the orbit of Neptune. The thirty-third largest known body in the Solar System, it is the only one identified orbiting entirely within the orbit of Neptune that is a dwarf planet. Composed of rock and ice, Ceres is estimated to comprise approximately one third of the mass of the entire asteroid belt. Ceres is the only object in the asteroid belt known to be unambiguously rounded by its own gravity.

From Earth, the apparent magnitude of Ceres ranges from 6.7 to 9.3, and hence even at its brightest, it is too dim to be seen with the naked eye, except under extremely dark skies. Ceres was the first asteroid discovered, by Giuseppe Piazzi at Palermo on 1 January 1801. It was originally considered a planet, but was reclassified as an asteroid in the 1850s when many other objects in similar orbits were discovered. Ceres appears to be differentiated into a rocky core and icy mantle, and may harbor a remnant internal ocean of liquid water under the layer of ice. The surface is probably a mixture of water ice and various hydrated minerals such as carbonates and clay. In January 2014, emissions of water vapor were detected from several regions of Ceres. This was unexpected, because large bodies in the asteroid belt do not typically emit vapor, a hallmark of comets. The robotic NASA spacecraft Dawn entered orbit around Ceres on 6 March 2015. Pictures with a resolution previously unattained were taken during imaging sessions starting in January 2015 as Dawn approached Ceres, showing a cratered surface.

Two distinct bright spots (or high-albedo features) inside a crater, incorrectly reported as observed in earlier Hubble images, were seen in a 19 February 2015 image, leading to speculation about a possible cryovolcanic origin or outgassing. On 3 March 2015, a NASA spokesperson said the spots are consistent with highly reflective materials containing ice or salts, but that cryovolcanism is unlikely. On 11 May 2015, NASA released a higher resolution image showing that, instead of one or two spots, there are actually several. Mission > Background | Dawn Mission Solar System History Solar System Origins In the beginning in a cold gas cloud near where the solar system lies today, there was a competition between a physical process, gravitational collapse, and a chemical process, the formation of dust and rocks. When stars formed the strong UV light emitted by the stars evaporated the gas and stopped the formation of the dust, rocks and ultimately the planets. Such a competition is taking place today in the Trifid nebula (left) as imaged by the Hubble Space Telescope.

Trifid nebula "A cocoon nebula, perhaps the primordial solar nebula" by William K. Hartmann Inside the early solar nebula, the sun shone dimly in visible light as the dust and protoplanets formed as illustrated in a painting by W. Hartmann (right). In the region now called the asteroid belt, this process stopped when Jupiter formed by a gravitational instability. Again physical and chemical processes were in competition. Jupiter orbited the sun at a different rate than the protoplanets, closer to the sun, and its periodic gravitational pull stirred up the bodies in the "asteroid belt" shutting off the planetary formation process leaving baby planets a fraction of the size of Earth but very much indicative of the protoplanets that led to the formation of the terrestrial planets. The figure below shows Vesta and Ceres as seen by the Hubble Space Telescope and the Near-Earth asteroid Eros that was recently explored by the NEAR mission. These two bodies are much more massive than any body yet visited in this region of space and are truly small planets.

Ceres Giuseppe Piazzi pointing at Ceres Ceres, the largest asteroid and the first to be discovered, is named after the Roman goddess of agriculture. It was discovered by Giuseppe Piazzi of the Palermo Observatory on Jan. 1, 1801. Additional observations by Piazzi were cut short due to illness. Carl Friedrich Gauss, at the age of 24, was able to solve a system of 17 linear equations to determine Ceres' orbit and to allow it to be rediscovered, a remarkable feat for this time. As a result within one year of its initial discovery, both Heinrich Olbers and Franz von Zach were able to relocate Ceres. It revolves around the Sun in 4.6 terrestrial years and has a diameter estimated at about 960 km (600 miles). Vesta Vesta, the brightest asteroid, is named for the ancient Roman goddess of the hearth and is the only asteroid ever visible with the naked eye. Found on March 29, 1807, by Heinrich Olbers, it was the fourth minor planet to be discovered. It is the second most massive and the third largest asteroid.

It revolves around the Sun in 3.6 terrestrial years and has an average diameter of about 520 km(320 miles). Its surface composition is basaltic. More Background Asteroids: The discovery of asteroids / ESA history / Welcome to ESA / About Us / ESA Asteroids: The discovery of asteroids Asteroid 243 Ida and its newly discovered moon, Dactyl During the 18th century, astronomers were fascinated by a mathematical expression called Bode's law. It appeared to predict the locations of the known planets, but with one exception... Bode's law suggested there should be a planet between Mars and Jupiter. When Sir William Herschel discovered Uranus, the seventh planet, in 1781, at a distance that corresponded to Bode's law, scientific excitement about the validity of this mathematical expression reached an all-time high. Many scientists were absolutely convinced that a planet must exist between Mars and Jupiter. By the end of the century, a group of astronomers had banded together to use the observatory at Lilienthal, Germany, owned by Johann Hieronymous Schröter, to hunt down this missing planet. They called themselves, appropriately, the 'Celestial Police'.

Despite their efforts, they were beaten by Giuseppe Piazzi, who discovered what he believed to be the missing planet on New Year's Day, 1801, from the Palermo Observatory. The new body was named Ceres but subsequent observations swiftly established that it could not be classed a major planet as its diameter is just 940 kilometres (Pluto, the smallest planet, has a diameter is just over 2300 kilometres). Instead, it was classified as a 'minor planet' and the search for the 'real' planet continued. Between 1801 and 1808, astronomers tracked down a further three minor planets within this region of space: Pallas, Juno and Vesta, each smaller than Ceres. It became obvious that there was no single large planet out there and enthusiasm for the search waned. A fifth asteroid, Astraea, was discovered in 1845 and interest in the asteroids as a new 'class' of celestial object began to build. In fact, since that time new asteroids have been discovered almost every year. It soon became obvious that a 'belt' of asteroids existed between Mars and Jupiter. This collection of space debris was the 'missing planet'.

It was almost certainly prevented from forming by the large gravitational field of adjacent Jupiter. Now there are a number of telescopes dedicated to the task of finding new asteroids. Specifically, these instruments are geared towards finding any asteroids that cross the Earth's orbit and may therefore pose an impact hazard. Rate this

Question: What is the largest and first discovered (by Piazzi at Palermo in 1801) of the minor planets?
Answer: Ceres