In 1849 he was called back to Rome to take charge of the direction of the Observatory at the Collegio Romano as successor of prematurely departed Father Francesco De Vico (1805-1848). Secchi, soon aware of the limitations of the structure that hosted the observatory, obtained permission in 1852 to transfer it in new rooms in the rooftop of St. Ignatius church. This relocation allowed him to renew the instrumentation and at the same time create a modern astronomic, meteorological and geomagnetic observatory. Secchi was aware of the importance of communicating the scientific results and relaunched the Memorie dell’Osservatorio del Collegio Romano (Memoirs of the Collegio Romano Observatory) where the main astronomic studies carried out in the observatory were gathered. In addition, he promoted the publication of the Bullettino Meteorologico del Collegio Romano (Meteorological Bulletin of the Collegio Romano), which collected the meteorological data of various stations and published contributions related to astronomy and related sciences.
Reproduction of a table from Le Soleil which represents the spectroscope used by Secchi for his studies of solar physics. A combination of prisms, positioned in the focus of the telescope he utilized, splits the light such that the solar chromosphere is observed in one of the lines due to hydrogen.