This work contains a survey of the constellations and a cosmological dialogue, Lo Spaccio de la Bestia Trionfante (The Expulsion of the Triumphant Beast, 1584). Bruno, a Dominican astrologer and philosopher, affirmed that the universe is infinite, having no center. Distant stars have their own inhabited planets. In 1600, Bruno was burned at the stake in Rome. Bruno was executed on account of his theological beliefs, particularly his denial of the Trinity and of the deity of Christ. His death underscores the potential hazards facing natural philosophers who wrote about theological topics in Catholic realms.