The museum was opened in 1989, as a tribute to the priest Mr Ramón María Aller Ulloa, who was a renowned astronomer and mathematic born in Lalín in 1878 and died in 1966. The old residency of the scientist was adapted for the museum. The old building from the 19th century was the first space observatory of Galicia. The office, furniture and instruments that Aller Ulloa used for his works are preserved, as well as the documents, photographs and many books from his personal library.