Heinrich Louis d'Arrest was a German astronomer born on March 13, 1822, in Berlin. He is best known for his discovery of the comet 1861 I, which was later named after him. D'Arrest made significant contributions to the field of astronomy, particularly in the study of celestial bodies and their orbits. In addition to his work on comets, d'Arrest was involved in the establishment of the Berlin Observatory and collaborated with other prominent astronomers of his time. He passed away on December 14, 1875, leaving a legacy in the scientific community for his discoveries and advancements in observational techniques.