Giovanni Domenico Cassini Biography and Timeline

Jupiter Permanent Spot

Records a persistent oval feature at the latitude associated with Jupiter's later Great Red Spot.

Role range: 1625-1712

Jupiter Rotation

Uses atmospheric markings to estimate Jupiter's rapid rotation period.

Role range: 1625-1712

Discovery of Lapetus

Discovered by Giovanni Domenico Cassini as he was studying Saturn and its rings, Cassini guessed correctly that Iapetus was tidally locked to Saturn, and that one half of the planet was bright, and the other half was dark

Tables of Jupiter Moons

Improves tables predicting eclipses and motions of Jupiter's satellites.

Role range: 1625-1712

Discovery of Lapetus

Lapetus is Saturns third largest moon, measuring 1,470 km across, the 11th largest moon in the Solar System

Cassini Joins Paris Astronomical Programme

Giovanni Domenico Cassini moved to Paris to participate in the astronomical work encouraged by the French monarchy.

Mars Parallax Observations Coordinated

Cassini organised observations used to estimate the distance to Mars, contributing to calculations of the scale of the Solar System.

Academy Supports Paris Observatory Work

The Academy's astronomers used the developing Paris Observatory for systematic observations of planets and stars.

Academy Encourages Astronomical Instrument Improvements

The Academy's researchers refined observational instruments needed to compare celestial measurements across different sites.

Academy Researchers Extend Geographic Surveys

French astronomers continued applying triangulation and astronomical methods to improve geographical measurements.

Cassini Observes Major Comet

Cassini participated in the period's intensive astronomical study of the great comet visible in 1680.

Academy Studies Celestial Motions

Parisian academicians compared observations of planetary and lunar movements to improve astronomical calculations.

Academy Publishes Natural History Research

The Academy's naturalists advanced detailed descriptions of animals, plants and anatomical structures through collaborative research.

Scientific Memoirs Circulate through Academy

Research communicated in the Academy's meetings helped disseminate mathematical and experimental findings among French scholars.

Louis XIV Issues Academy Regulations

The king granted the Academy formal regulations on 20 January, clarifying its structure and royal supervision.

Academy Established at Louvre

The reformed Royal Academy of Sciences maintained its institutional headquarters in the Louvre in Paris.

Royal Appointment System Formalised

The regulations provided for royal appointment of academicians following nominations by the Academy.

Scientific Disciplines Receive Defined Sections

The Academy's organisation distinguished fields including geometry, astronomy, mechanics, anatomy, chemistry and botany.

Academy Advances Scientific Publication

The Academy increasingly circulated reports and memoirs of investigations conducted under its new formal structure.

Cassini Continues Meridian Research

Academicians continued comparing meridian measurements to improve geographical surveying and assess the Earth's figure.