The Life of Fathe Angelo Secchi

Born in June, 1818 Father Pietro Angelo Secchi was a pioneer in the field of astronomical spectroscopy and the director of the Observatory of the Roman College in Rome.

Father Secchi was born in the town of Reggio Emilia in northern Italy. As a child, he studied at the Jesuit Gymnasium in his home town, until he was 16. It was at that time that he entered the Jesuit Order. Shortly afterward, he went to Rome to continue his studies where he showed great scientific aptitude.

In 1839, Father Secchi became the math and physics tutor at the Roman College, not far from the Vatican in Rome. In 1840, Father Secchi became a professor of physics in the Jesuit University in Loreto.

In 1844, Father Secchi returned to Rome where he began to study for the Priesthood. He was eventually ordained in 1847. In 1848, the Jesuits were forced to leave Rome as a result of the Roman Revolution, an attempt to replace the Papal State with a democratically elected government.

Father Secchi’s Career

During the next two years, Father Secchi taught at Stonyhurst College in Britain and at Georgetown University in Washington DC. While in the United States, Father Secchi became friends with Commander Mathew Fontaine Maury, the first director of the United States Naval Observatory. Father Secchi studied briefly with Commander Maury and corresponded with him for many years.

In 1850, Father Secchi returned to Rome, where he became the director of the Observatory of the Roman College. Under his care, the Observatory was moved to its current location on the roof of St. Lazarus Cathedral.

Beginning in 1870, Father Secchi’s position was challenged by the newly formed Kingdom of Italy, when it absorbed the remainder of the Papal State, in and around Rome. In 1873, the Kingdom of Italy took control of the Roman College, and in 1875, tried to take control of the Observatory. Father Secchi protested and threatened to accept one of the many positions offered to him by foreign observatories. As a result, Father Secchi was given a number of important scientific and political dignities, and was not required to swear allegiance to the King of Italy.

Father Secchi’s Legacy

Over the course of his career, Father Secchi made a number of important contributions to the science of astronomy. He drew accurate maps of the moon and Mars, discovered three comets and drew an accurate map of Copernicus Crater, on the surface of the moon.

Father Secchi’s main area of study was astronomical spectroscopy, which is the study of light and colour given off by distant stars and galaxies. Father Secchi demonstrated that the light given off by the sun is absorbed by Earth’s atmosphere. In doing so, he was one of the first astronomers to demonstrate that the sun is a star.

Beginning in 1863, Father Secchi began collecting spectral images of distant stars, eventually collecting more than 4,000 stellar spectrograms. Through a careful analysis of this data, Father Secchi discovered that stars come in a limited number of distinct categories. Using this information, Father Secchi developed the first system of stellar classification, the Secchi Classes. Even though this method was eventually supplanted by the Harvard System, Father Secchi is still remembered as an important pioneer in the development of astrophysics, thanks to his discovery of stellar classification.

Father Secchi died in 1878 at the age of 59.


Maffeo, Fr. Sabino, SJ; trans. Fr. George Coyne, SJ (1991). In the Service of Nine Popes: 100 Years of the Vatican Obervatory. Città del Vaticano (Vatican City): Specola Vaticana.


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