Giuseppe Campani was an Italian

Italy

Italy , officially the Italian Republic languages]] under the European Charter for Regional or Minority Languages. In each of these, Italy's official name is as follows:;;;;;;;;), is a unitary parliamentary republic in South-Central Europe. To the north it borders France, Switzerland, Austria and...

 optician and astronomer

Astronomer

An astronomer is a scientist who studies celestial bodies such as planets, stars and galaxies.Historically, astronomy was more concerned with the classification and description of phenomena in the sky, while astrophysics attempted to explain these phenomena and the differences between them using...

 who lived in Rome

Rome

Rome is the capital of Italy and the country's largest and most populated city and comune, with over 2.7 million residents in . The city is located in the central-western portion of the Italian Peninsula, on the Tiber River within the Lazio region of Italy.Rome's history spans two and a half...

 during the latter half of the 17th century.

His brother, Matteo Campani-Alimenis

Matteo Campani-Alimenis

Matteo or Mathieu Campani-Alimenis was a mechanician and natural philosopher of the 17th century.He held a curacy at Rome in 1661, but devoted himself principally to scientific pursuits...

, and he were experts in grinding and polishing lenses

Lens (optics)

A lens is an optical device with perfect or approximate axial symmetry which transmits and refracts light, converging or diverging the beam. A simple lens consists of a single optical element...

, especially for very long focal length

Focal length

The focal length of an optical system is a measure of how strongly the system converges or diverges light. For an optical system in air, it is the distance over which initially collimated rays are brought to a focus...

 aerial telescope

Aerial telescope

An aerial telescope is a type of very-long-focal-length refracting telescope built in the second half of the 17th century that did not use a tube. Instead, the objective was mounted on a pole, tree, tower, building or other structure on a swivel ball-joint. The observer stood on the ground and held...

 objectives

Objective (optics)

In an optical instrument, the objective is the optical element that gathers light from the object being observed and focuses the light rays to produce a real image. Objectives can be single lenses or mirrors, or combinations of several optical elements. They are used in microscopes, telescopes,...

. The astronomer Cassini

Giovanni Domenico Cassini

This article is about the Italian-born astronomer. For his French-born great-grandson, see Jean-Dominique Cassini.Giovanni Domenico Cassini was an Italian/French mathematician, astronomer, engineer, and astrologer...

 made many of his discoveries with these lenses.

Campani also made many observations himself. Cassini called his attention to the spots on Jupiter

Jupiter

Jupiter is the fifth planet from the Sun and the largest planet within the Solar System. It is a gas giant with mass one-thousandth that of the Sun but is two and a half times the mass of all the other planets in our Solar System combined. Jupiter is classified as a gas giant along with Saturn,...

, and he disputed with Eustachio Divini

Eustachio Divini

Eustachio Divini was an Italian manufacturer and experimenter of optical instruments for scientific use in Rome.-The origins:Eustachio was born on 4 October 1610 in San Severino Marche, from the illustrious Divini's family...

, an Italian optician, the priority of their discovery. His astronomical observations and his descriptions of his telescopes are detailed in the following papers: Ragguaglio di due nuovi osservazioni, una celeste in ordine alla stella di Saturno, e terrestre l'altra in ordine agl' instrumenti (Rome, 1664, and again in 1665); Lettere di G. C. al sig. Giovanni Domenico Cassini intorno alle ombre delle stelle Medicee nel volto di Giove, ed altri nuovi fenomeni celesti scoperti co' suoi occhiali (Rome, 1666).

His brother, mentioned above, is also noted as a mechanician for his work on clocks. He was a priest in charge of a parish in Rome. Louis XIV of France

Louis XIV of France

Louis XIV , known as Louis the Great or the Sun King , was a Bourbon monarch who ruled as King of France and Navarre. His reign, from 1643 to his death in 1715, began at the age of four and lasted seventy-two years, three months, and eighteen days...

 ordered several long-focus lenses (86, 100, 136 feet respectively) for Cassini, who discovered with their aid additional satellites of Saturn

Saturn

Saturn is the sixth planet from the Sun and the second largest planet in the Solar System, after Jupiter. Saturn is named after the Roman god Saturn, equated to the Greek Cronus , the Babylonian Ninurta and the Hindu Shani. Saturn's astronomical symbol represents the Roman god's sickle.Saturn,...

.