1802, it was found that binary stars move periodically with each other (F. Herschel, England).

1809 published the book "the theory of celestial bodies moving according to conic curves", and put forward the calculation method of planetary orbits (Gauss, Germany).

18 15 years, a spectroscope consisting of a straight tube, a prism and a telescope was manufactured, which resulted in "astronomical optics" and the discovery of the black absorption line in the solar spectrum (Fraunhofer, Germany).

1823, he put forward the "luminosity paradox" of classical cosmology (Olbers).

From 1833 to 1847, 3347 pairs of binary stars and 825 nebulae were discovered (John Herschel, UK).

1837, the positions of two stars were accurately measured with a hairspring micrometer, and many new binary stars (Struve, Russia) were found.

1837 The solar radiant heat was first measured (Puye, France, J Herschel, England).

From 1838 to 1839, the annual parallax of stars was measured for the first time, which provided strong evidence for the revolution of the earth (Bessel, Struve, Henderson, England).

1843 The number of sunspots was found to change periodically around 1 1 year (Schwab, Germany).

1844 discovered the brightness grade method for observing variable stars, which promoted the rapid development of variable star research (Agrander, Germany).

1844, according to the irregular changes in the movements of Sirius and Nanhe, it was predicted that they both had dark companions (Bessel, Germany).

1845, the first photo of the sun was taken, which was used to study the solar activity (Fessofoucault, France).

1845, according to the irregularity of Uranus' motion, a new planet (john adams, Britain, Le Verrier, France) was predicted.

1846, according to the prediction calculated by the perturbation theory of planetary orbits, Neptune was discovered, the law of universal gravitation was verified, and Copernicus' solar system theory was confirmed (Galle, Germany).

1846, Neptune's first satellite, Wei Yi (Russell, England), was discovered.

1847 ——1877 Considering the mutual perturbation between planets, the table of planetary motions was rewritten and the precession phenomenon of Mercury's perihelion was discovered (Le Verrier, France).

1848, Saturn's moon Titan was discovered.

1849 put forward the theory of satellite stability, which proved that Saturn's ring is not a continuous solid, but consists of countless small particles (Roche, France).

1850 Some nebulae have spiral structures (William Ross, UK).

185 1 year, two satellites of Uranus were discovered-Tianwei-1 and Tianwei-2 (Russell, England).

185 1 year, it is found that geomagnetic and magnetic storms also have periodic changes of 1 1 year corresponding to the change of sunspot number (Lamont, Germany, Sabine, England).

1852 compiled the Bonn catalogue (Agrander, Germany).

1854 put forward the gravitational contraction hypothesis of solar energy, which holds that the sun gradually contracts due to its own gravitational action, and the potential energy is converted into heat energy, maintaining the energy it radiates outward (Helmholtz, Russia).

1857, the first successful photo of stars was taken, and star photography was started (Bond, USA).

1857 ——1859 photographed the moon with clear details for the first time (De La Rue, England).

Establish the basic relationship between celestial luminosity and magnitude (Bergson, England).

1858, from the rotation of sunspots on the surface of the sun, it was found that the sun does not rotate like a solid, but like a fluid (carrington, England).

1858 discovered the periodic variation of the latitude distribution of sunspots on the solar surface (Spey, Germany, Carrington, England).

/kloc-solar flare was discovered in 0/859, and geomagnetic disturbance, magnetic storm and aurora occurred simultaneously (carrington, England).

1859 invented the photometer, which has been improved and used up to now (sellner, Germany).

186 1 year, the first photometric catalogue containing 226 bright stars was published (sellner, Germany).

1862, according to Bessel's prediction, Sirius's dark companion was discovered. Prove that the law of universal gravitation is also applicable to the study of celestial bodies outside the solar system (A. Clark, USA).

From 1863 to 1864, the chemical composition of stars and nebulae was studied, and the chemical identity of celestial bodies was further confirmed (Sage, Italy, Huggins, UK).

1863 compiled the first AGK Basic Catalogue (hosted by Orville, Germany, with international cooperation).

1864 studied nebulae with spectroscope, revealed their gas structure and found two special green spectral lines emitted by planetary nebulae. (hagens, England).

1865, some bright stars were found to contain elements such as sodium, iron, calcium, magnesium and bismuth through spectral analysis (hagens, UK).

1866- 188 1 found that the spectrum of comets contains hydrocarbons, and confirmed that comets not only reflect sunlight, but also emit light themselves. The gas spectrum of a meteor is similar to that of a comet, indicating that the two celestial bodies are related (hagens, UK).

1868

Chromosphere was discovered, the middle atmosphere of the sun, helium was discovered on the sun, and helium was later discovered on the earth (Rockall, England).

Using a spectroscope, the prominence was first observed, but it was not an eclipse (Zhan Sen, France).

The visible spectral classification of star spectra is put forward for the first time, which divides stars into four categories: white stars, yellow stars, orange stars and red and dark red stars (Sage, Italy).

The first determination of the apparent velocity of a star (Huggins, England).

In 1869, the wavelength of 1000 spectral lines in the solar spectrum was published and expressed in a new unit angstrom (Egstrom, Sweden).

1870 discovered the flash spectrum of the sun and a special green spectral line emitted by the corona, which was once considered as a new element, but was proved to be the forbidden line of iron, nickel and calcium in 194 1 year (Richard Young, USA).

187 1 year, the rotation speed of the sun is measured from the displacement of the spectral lines on the east and west sides of the sun (vogel, Germany).

1874, it was found that bright stars up to level 4 were concentrated in the big garden at an angle of 17 degrees with Silver Road (Gould, USA).

1876, the dynamic theory of gap region in asteroid belt and slit formation in Saturn's ring was put forward (Kirkwood, USA).

1877

It is suggested that there are "artificial canals" on the surface of Mars (Schiaparelli).

Discovery of Two Small Satellites on Mars-Phobos and Phobos (Hall A, USA).

It is found that (crystalline) selenium is in contact with metal, which produces the photovoltaic effect of electromotive force under light irradiation. It was used by American freese in 1883 (Walter Adams, UK) to make photovoltaic cells.

The theory of sound was published, which basically completed the mathematical theory of sound (Rayleigh, England).

1878, according to the repulsion of solar radiation, the comet shape theory was established, and the comet tails were divided into three types (bulykin, Russia).

1879

The theory of tidal friction is established, from which the theory of the origin of the moon is put forward. People believe that the earth was pulled out by the tidal force of the sun and formed the moon (Joe Darwin, England).

Using the empirical formula between blackbody radiation and temperature, it is found that the surface temperature of the sun is 6000 degrees Celsius (Stefane, Austria).

From 1879 to 1882, a large-scale photometric catalogue of the measured magnitude of 4260 stars was compiled by using polarization photometer (Love Pickering Company, USA).

1880 put forward the classification of variable stars (American love Pickering).

188 1 year, the solar constant value of surface thermal radiation was accurately measured by resistance bolometer, and the research on solar radiation began (Ringler, USA).

188 1 year, the first comet photo was taken (Delapa de Zhan Sen, USA).

1882, observation confirmed that the long-term precession of Mercury perihelion was out of tolerance, and its data calculation was accurate. Newcomb, USA.

1885- 1886, and established the spectral classification of stars (American Pickering, Emory).

1887 compiled a catalogue of photographic sky maps (under the responsibility of Henry brothers of Paris Observatory, with international cooperation).

1887, according to the different spectra of stars, the theory of star evolution was put forward to explain that stars are changeable (Rockell, England).

1888

Publication of "New General Catalogue" (N.G.C) (Derel, UK).

It is found that the apparent velocity of Daling pentavariable star changes periodically, which proves that it is an eclipse star (Vogel, Germany).

Discovery of the spiral structure of Andromeda nebula through photographic observation (Roberts, UK).

1889 The first split binary star (Pickering, Ann, Murray) was discovered.

1890, the mutual perturbation between Saturn and Jupiter was studied, and an accurate theory of the motion of the two planets was established (Joe Hill, USA).

189 1 year, he invented the solar spectrophotometer and obtained the solar spectrogram (Hull, USA, Delandale, France).

1892, the fifth satellite of Jupiter-Ganymede (Barnard, USA) was discovered.

1892, according to Bessel's prediction, the dark companion star of Nanhesan (Scheber, USA) was discovered.

1894, he put forward the "Seligr" of classical cosmology.

From 65438 to 0895, the meteorite structure of Saturn's rings was confirmed by spectral analysis (Keeler, USA).

1898, Saturn's moon Titan was discovered.

1898, eros was discovered. This asteroid is less than 24 million kilometers from the Earth recently, so it is used to measure the solar parallax (Witt, Germany).