OUTLINE OF 18TH CENTURY ASTRONOMY
 -------------------------------
 John Pazmino
 NYSkies Astronomy Inc
 nyskies@nyskies.org
 www.nyskies.org
 2003 August 5 initial
 2013 December 10 current
    At the Observing Group meeting of 12 July 2003 I presented an
overview of astronomy during the 1700s. I had hand-written notes to
cue me. Here are my notes in finished form, with many additional
items suggested since then. I confine to items distinctly 'astronomy', 
leaving out collateral fields like chemistry, industry, biography, 
and general world affairs. 
    Apart from minor editing and some addition of new items, the 
major change is the collapse of the categories for the entires. It got 
too fiddly to put an entry in a one category where it could be valid 
for several. Here, entries are now listed seriatim and divided by 
decade. I update this article irreguarly as readers advise me of new 
items of interest. 
    The year for each item is sometimes uncertain in the  litterature. 
It may be year the work was actually done or that when the work was 
published or announced. 
    1700-1709
    --------- 
    1700 - Roemer invents meridian transit telescope 
    1700 - Boyle, Lord of Orrery, invents hand-driven model of solar 
         system 
    1700 - Delisle perfects celestial geodesy 
    1701 - ENGLAND issues charts with compass variation contours 
    1702 - Hauksbee shows that electrcity makes rarified air glow, 
         hints at cause of aurora 
    1702 - Halley issues first map of geomagnetic field, first use of 
         contour lines in cartography
    1702 - Gregory writes first astronomy textbook with Newton gravity 
    1704 - Newton issues corpuscular theory of light 
    1705 - Halley proposes periodic comets, predicts return of 
         'Halley's comet' 
    1705 - Flamsteed issues 1st part of most accurate star catalog 
    1706 - Stannyan discovers prominences during solar eclipse 
    1708 - Jupiter's 'great red spot' reappears, gone since 1680s 
    1710-1719 
    ---------
    1710 - end of Maunder sunspot drought on Sun 
    1712 - bootleg unverified Flamsteed catalog is issued 
    1713 - Newton issues updated 'Principia' 
    1714 - ENGLAND opens contest for finding longitude at sea 
    1714 - Whiston & Ditton propose contest for finding longitude 
    1714 - Leibniz proposes space & time can not be absolute 
    1715 - Halley discovers 'Baily's beads' during solar eclipse 
    1715 - Halley does first accurate calcs of solar eclipse path
    1716 - Halley shows aurora rays converge by perspective effect 
         and align with Earth magnetic field 
    1716 - France opens contest for determining longitude 
    1716 - Halley proposes Venus transit for fixing Earth-Sun distance 
    1718 - Cassini proposes Earth is prolate (it's really oblate)
    1718 - Halley discovers proper motion of stars  
    1719 - Maraldi makes first detailed Mars map, fixes rotation 
    1719 - Maraldi explains changes of Mars polar caps as ice 
    1719 - Whiston issues first map of magneic inclination 
    1719 - Stupendous aurora erupts over Europe starting modern 
         scientific study of northern lights 
    1720-1729 
    ---------
    1720 - Halley studies 'Olber's paradox' 
    1721 - Berkeley proposes matter-space interaction 
    1721 - Whiston shows magnetic incliantion to find longitude 
    1722 - Graham discovers daily shift of geomagnetic feild 
    1722 - Hadley makes first practical reflector telescope 
    1724 - Maraldi shows corona is part of Sun, not Moon 
    1724 - Graham, also Celsius, discovers geomagnetic storm by 
         violent agitation of marine compass 
    1725 - Flamsteed posthumously issues most accurate staratlas, uses 
         'Flamsteed' designations 
    1725 - Thiout builds clock for true, not mean, solar time 
    1727 - Schulze discoveres photochemical effect in silver nitrate. 
    1727 - Bradley discovers aberration as effect of light speed 
    1728 - Bianchini fixes Venus rotation (wrong, until spacecraft 
         measurements in 1960s.) 
    1729 - Bouger invents photometer 
    1729 - Bouger describes light attenuation thru glass plates 
    1729 - Motte translates Newton's 'Principia' into English
 
    1730-1739 
    ---------
    1731 - Hadley, and Geoffrey, invents marine quadrant 
    1731 - Bevis discovers Crab Nebula, later catalogued by Messier 
    1732 - duChatelet shows radiant heat behaves much like light
    1733 - Hall invents achromatic refractor 
    1733 - Celsius explains aurora borealis 
    1734 - FRANCE finally accepts Newton gravitation theory 
    1735 - deCondamine fixes curvature of Earth 
    1735 - France sends teams to Ecuador and Lapland to measure 
         shape of the Earth 
    1735 - Harrison invents mechanical clock for longitude
    1736 - Euler applies differential equations to Newton mechanics 
    1737 - Bevis observes first planet-planet occultation, Venus over 
         Mercury 
    1737 - deMaupertuis proposes Earth is oblate, not prolate 
    1738 - Smith issues 'Opticks', 1st book on telescpe making 
    1738 - Delisle invents heliographic coordinate system 
    1739 - Winthrop starts first routine monitoring of sunspots 
    1739 - deMaupertuis fixes oblatitude of Earth 
    1739 - Halley confirms secular acceleration of Moon, first 
         noticed in 1692 
    1740-1749 
    ---------
    1740 - Short starts selling first commercial reflectors 
    1740 - duChatelet explains relation of momentum, energy, mass
    1740 - Stukely discovers solstice alignment at Stonehenge 
    1740 - Bouguer discovers gravity variation around world 
    1742 - Celsius invents inverse centigrade temperature scale 
    1742 - Maclaurin explains spherical shape of planets 
    1743 - Christin invents 'Celsius' temperature scale 
    1743 - d'Alembert uses energy concept in Newton gravity theory 
    1743 - Clairaut shows Mewton's theory of Earth shape is correct
    1743 - Clairaut calcs variation of gravity on oblate Earth 
    1744 - Pope allows Galileo's 'Dialogue ...' to publish only with 
         his denial of Copernicus system in it 
    1744 - Cassini makes first national geodetic survey, in France 
    1744 - duCheseaux studies 'Olbers's paradox' 
    1745 - Laplace proposes Earth is splash of Sun after comet 
         collision 
    1745 - Bevis makes most detailed staratlas, never published 
    1746 - Euler explains refraction by wave theory of light 
    1747 - Clairaut first solves of 3-body problem for Moon 
    1747 - Clairaut proposes Newton's theory of Moon is deficient
    1748 - Bradley discovers Earth nutation, predicted by Newton 
    1748 - Lomonosov discovers conservation of mass & energy 
    1749 - Clairaut realizes Newton's theory of Moon is correct
    1749 - D'Alembert refines theory of precession and nutation
    1749 - Dunthorne confirms secular acceleration of Moon 
    1749 - Melvill builds spectroscope, studies spectrum lines 
    1749 - duChatelet translates Princioia into French with comments
    1750-1759 
    ---------
    1750 - Mayer invents selenographic coordinate system 
    1750 - Wirgentan finds magnetic disruptions coincide with 
         strong auroral activity
    1750 - Michell discovers inverse square law for magnetism
    1750 - Mayer designs first lunar globe, never built 
    1750 - Wright proposes island universes and plurality of worlds 
    1752 - Melvill studies brightline spectra in flames 
    1752 - Mayer improves lunar-distance method for finding longitude 
    1752 - LaCaille issues cluster & nebula catalog of south skies 
    1754 - Dolland invents heliometer 
    1754 - Mairan publishes first textbook on aurorae 
    1754 - Maclaurin posthumously proposes Jupiter is a fluid body 
    1754 - Kant proposes secular acceleration of Moon motion is due ro 
         Earth slowdown 
    1754 - Maclaurin papers show gravity of fluid planets 
    1755 - Kant proposes solar system formed from nebula 
    1755 - Kant proposes 'Oort cloud' for comet origin 
    1756 - Cantor discovers first disruptions in geomagnetic field 
    1756 - Lomonosov argues for wave nature of light 
    1757 - Dolland perfects achromatic refractor 
    1757 - Campbell, and Bird, invents marine sextant 
    1757 - Clairaut fixes best ever mass of Moon and planets 
    1758 - Palitzsch finds Halley's comet, first comet whose future 
         return path was predicted
    1758 - Halley's comet returns, first periodic comet 
    1758 - Messier recovers Crab Nebula, starts catalog of nebulae
    1759 - Cantor discovers seasonal shift of geomagnetic field
    1759 - Cantor sets up 'C-number' rating for geomagnetism 
                                                                    
    1760-1769 
    ---------
    1760 - Lambert studies diffuse reflection, invents 'albedo'
    1760 - Lambert makes first photometry of planet albedo 
    1768 - Euler proposes aether to carry light waves 
    1761 - Lambert proposes Milky Way is heaps of star clusters 
        confined within a disc 
    1761 - Lomonosov discovers atmosphere of Venus during transit 
    1761 - Maskelyne perfects lunar-distance method for longitude 
    1761 - Harrison invents sea-worthy clock for longitude
    1761 - 1st of 18th century Venus transits
    1761 - Lambert calculates transfer trajectories between planets 
    1764 - Lagrange explains lunar librations 
    1765 - Euler predicts Chandler motion of Earth poles 
    1765 - Winthrop makes first calculation of comet's mass 
    1766 - Titius explains gap in planet orbits, now 'asteroid belt' 
    1767 - Michell proposes binary star systems 
    1767 - Michell assesses Vega is ~460,000 AU (~7.2 LY) away 
    1767 - Maskelyne begins publishing 'Nautical almanac and 
         astronomical ephemeris' 
    1767 - Rittenhouse invents clock-driven model of solar system 
    1768 - Rittenhouse fields first American temam for Venus transit
    1769 - 2nd of 18th century Venus transits 
    1770-1779
    ---------
    1770 - Messier discovers comet Lexell, notes it as Earth threat 
    1772 - Messier issues 1st part of cluster & nebula catalog 
    1772 - Bode issues Titius-Bode relation of planet orbits 
    1772 - Lagrange discovers libration points in gravity field 
    1773 - Herschel starts study of proper motions of 13 stars 
    1773 - Capt Cook 1st European to observe aurora australis 
    1774 - Wilson discovers depression of sunspots below photosphere 
    1774 - Herschel builds own first telescope 
    1774 - Maskelyne measures gravity pull of nearby mountain 
    1775 - Mayer issues first topograohic map of Moon 
    1776 - Lexell, also Prosperin, calculate ellipse orbit for 
         Lexell's comet, first short-period comet 
    1776 - Lexell discovers 1767 Jupiter interaction with comet Lexell 
    1777 - Mudge invents remelt process for metal mirrors 
    1777 - Mudge perfects zonal test of parabolic mirrors 
    1778 - Herschel begins Jupitter studies, discovers three large 
         'SL9' spots 
    1778 - Franklin explains atmospheric circulation among climata 
    1778 - Franklin explains aurora as electrical discharges 
    1779 - Olbers invents new method to calculate comet orbits 
    1779 - Herschel invents filar micrometer 
    1779 - Darquier explains globular (planetary) nebulae 
    1779 - Lexell studies 1779 Jupiter-comet Lexell interacton, shows 
         comet mass less than 1/9,000 of Earth. 
    1780-1789
    ---------
    1780 - Williams rediscovers 'Baily's beads' in solar eclipse 
    1780 - Herschel discovers 'Encke's division' in Saturn B ring 
    1781 - Herschel discovers Uranus, first new planet since antiquity 
    1781 - Herschel shows Earth-Mars similarity of seasons 
    1781 - Herschel questions Earth as stable clock. based on 
         Jupiter's variable rotation. 
    1781 - Lexell, also Olbers, shows Uranus has a planet, not comet, 
         orbit 
    1781 - Maskelyne & Herschel stage telescope rally; Herschel wins 
    1781 - Messier discovers cluster of nebulae, Virgo galaxy cluster 
    1782 - Herschel discovers real binary stars, first is Castor 
    1782 - Goodricke discovers beta Persei & delta Cephei as variables 
    1782 - Goodricke proposes eclipsing binary stars 
    1782 - Herschel discovers Sun's motion thru local stars 
    1783 - Mechain shows many new nebulae in Virgo cluster, but 
         apparently never documented them 
    1783 - Michell proposes blackholes 
    1784 - Pigott discovers delta Cephei as variable 
    1785 - Hutton proposes Earth is several million years old 
    1785 - Herschel discovers millstone shape of Milky Way 
    1785 - vonZach searches for planet in Titius-Bode gap, gives up 
         with no finds by 1800 
    1785 - Laplace shows solar system has longterm dynamic stability
    1785 - Schroeter discovers clouds on Mars 
    1785 - Laplace develops field description for gravity 
    1786 - Herschel publishes best catalog of nebulae & clusters, 
         becomes by late 19th 'New General Catalog' 
    1786 - Gilpin begins regular records of geomagnetic field
    1787 - Laplace proposes Saturn has very many nested solid rings 
    1787 - Herschel discovers Uranus moons Titania & Oberon 
    1789 - Schroeter discovers solar photosphere granulation 
    1789 - Herschel builds 'Herschel' scope with 1.2m mirror 
    1789 - Russell builds first globe of Moon 
    1789 - Herschel discovers Saturn moons Mimas & Enceladus 
    1789 - Herschel measures Saturn ring thickness, ~500Km 
    1789 - Herschel discovers oblateness of Saturn 
    1789 - Herschel explains globular clusters 
    1789 - Herschel proposes Saturn has only two solid rings separated 
         by Cassini's division 
    1790-1799 
    ---------
    1790 - Michell builds first 'Cavendish' machine, never used 
    1791 - Banneker improves calculation of eclipses and Moon phases 
    1791 - Schroeter discovers lunar rimae (rilles) 
    1792 - Schroeter measures Venus atmosphere, about 14Km thick 
    1792 - Delambre & Mechain fix size of Earth, define the 'meter' 
    1794 - Chladni proposes meteors fall from outer space 
    1795 - Bowditch issues 'American practical navigator' 
    1795 - France adopts metric system of measures
    1795 - Pigott discovers R Coronae and R Scuti as variables 
    1796 - Laplace improves nebular origin of solar system 
    1797 - Olbers develops 'Olbers's' method of orbit calculation 
    1797 - Cavendish fixes Earth density by measuring Newton constant 
    1798 - Laplace, also Lagrange, shows stability of solar system 
    1798 - Laplace proposes blackholes 
    1798 - Brandes starts triangulation measures of meteors 
    1799 - Herschel measures rotation of Saturn ring, 10h 43m 
    1799 - vonHumboldt starts geomagnetic mapping of Atlantic OCean
    1799 - vonHumboldt makes first detailed study of Leonid meteors 
    1799 - Brandes & Brenzenberg show Leonids are ~97Km above ground 
    1799 - Herschel disocvers infrared radiation in sun spectrum