The Greatest Historical Astronomers

An interesting book entitled, “Human Accomplishment” by Charles Murray has attempted to select the most important figures in the arts and sciences from 800 BC to 1950 AD. A total of 4002 significant figures were culled from a large number of authoritative sources covering astronomy, physics, mathematics, chemistry, biology, earth sciences, technology, the various arts, and philosophy. Murray used statistical analysis as a guide to avoid selections based on nationality, gender, race, or popularity. I think he did a very credible job in his selection process. The top twenty people were ranked within each class. For example, the two most important figures in physics were Newton and Einstein, in mathematics, Euler and Newton, and in technology, Watt and Edison.

Of the 4002 significant figures selected, 124 were astronomers. 204 were chemists, 85 were in the earth sciences, 218 were physicists and 101 were mathematicians. As for the arts, there were 522 significant musicians and 1128 significant authors.

Here are his top twenty astronomers in rank order with accomplishments:

1.GALILEO Galilei (1564-1642)

Resolved the stars in the Milky Way, discovered sunspots and measured the Sun’s rotation, observed Venus phases, discovered four moons of Jupiter, observed lunar features and measured lunar wobble, supported the Copernican system of planetary movement via his observations.

2. KEPLER Johannes (1571 – 1630)

Using Brahe’s precise data derived his three laws of planetary elliptical motion, provided explanation of optical image formation through small apertures, the first enunciation of the inverse square law for intensity of illumination.

3. HERSCHEL William (1738 – 1822)

The discoverer of Uranus and several satellites of Saturn and Uranus, discovered that some double stars orbit each other, discovered infrared radiation, attempted to map the Milky Way’s shape, known for building state-of-the-art telescopes.

4. LAPLACE Pierre-Simon (1749 – 1827)

Postulated the solar system evolved from a large flattened cloud of gas, published differential equations describing planetary orbits and tides, determined the masses of Jupiter, Saturn and Uranus, applied probability theory to errors in observations.

5. COPERNICUS Nicolaus (1473 – 1543)

Proposed Earth orbited the Sun via De Revolutionibus Orbium Coelestium contradicting the long held Ptolomic belief that the Sun orbited the Earth thereby laying the groundwork for Galileo and Kepler.

6. PTOLOMY Claudius (2nd century AD)

Through his Almagest constructed an accurate geocentric model of the solar system consisting of a series of deferents and epicycles that was followed for 15 centuries until Copernicus.

7. BRAHE Tycho (1546 – 1601)

Chronicled supernova of 1572 and discovered it had no diurnal parallax proving it lay beyond the Moon, plotted the motion of the comet of 1577, accurately plotted motions of planets used by Kepler after his death.

8, HALLEY Edmond (1656 – 1742)

Astronomer Royal, discovered Omega Centauri, paid for publishing Newton’s Principia, using Newton’ gravitational law predicted the comet of 1682 would return in 76 years, invented the idea of using transits of Mercury and Venus to determine distance to the Sun.

9, CASSINI Giovanni (1625 – 1712)

Measured Mars and Jupiter rotation periods, first scientific records of zodiacal light, discovered the Cassini division, and investigated atmospheric refraction.

10, HIPPARCHUS of Nicaea(190 – 120 BC)

Founder of systematic observational astronomy, discovered the precession of the equinoxes, confirmed Eratosthenes value for the obliquity of the ecliptic, completed a catalog of 1080 stars.

11, BAADE Wilhelm (1893 – 1960)

Proposed supernova could produce cosmic rays and neutron stars, first resolved stars in Andromeda galaxy, defined Population I and II stars and two kinds of Cepheid variables.

12. HUBBLE Edwin (1889 – 1953)

Discovered the Hubble classification of galaxies, using Cepheid variables in M31 and M33 calculated their distances, showed that galaxy distribution was cosmologically uniform, showed galaxies were moving away from us at speeds proportional to their distance (Hubble’s Law).

13. BESSEL Friedrich (1784 – 1846)

Father of modern astrometry, published first accurate stellar parallax, discovered orbital deflections of Sirius and Procyon from unseen white dwarfs.

14, HUGGINS Sir William (1824 – 1910)

Invented the stellar spectroscope, comparing laboratory and stellar spectra demonstrated that the Orion nebula’s pure emission spectra indicated its gaseous nature while Andromeda galaxy had continuous spectra, imaged solar prominences in H Alpha light.

15, HALE George (1868 – 1938)

The first astrophysicist, invented the spectroheliograph allowing photography of solar prominences in daylight, discovered magnetic fields in sunspots, planned and completed the 200-inch Mt. Palomar telescope.

16, EDDINGTON Sir Arthur (1882 – 1944)

An astrophysicist, discovered the stellar mass-luminosity relationship, explained Cepheid variable pulsations and very high densities of white dwarfs, formulated the Eddington Limit which relates star’s maximum luminosity to its gravitational force.

17. HERTZSPRUNG Ejnar (1873 – 1967)

Studied stellar proper motions and motions of binary stars, using photography studied stellar brightness, compared stellar color ratios, plotted color-magnitude diagram for the Hyades cluster, which evolved to the Hertzsprung-Russell diagram. 

18. OLBERS Heinrich (1758 – 1840)

Discovered several comets, searched for missing planet between Mars and Jupiter forecasted by Bode’s Law and discovered Pallas and Vesta suggesting these were fragments of the missing planet, formulated Olber’s Paradox.

19, KUIPER Gerard (1905 – 73)

First planetary scientist, spectroscopically detected CH4 on Titan and CO2 on Mars, identified the comet-like debris of Kuiper’s Belt at the edge of the solar system.

20. HEVELIUS Johannes (1611 – 87)

An accomplished instrument maker, introduced the vernier scale for accuracy, developed a catalog of star positions and a celestial atlas, discovered four comets and was the first to observe a transit of Mercury.

Although one could quibble with the rank ordering of these great astronomers, it seems difficult to dislodge any from the list with anybody else. I recommend this book to anyone interested in the arts and sciences.

Mike Luciuk