A great gift idea for your grandpa who loves astronomy could be a telescope. It would allow him to observe the stars and planets up close and even take photographs of them. Another idea could be a book on space exploration or astronomy, such as "Cosmos" by Carl Sagan or "The Illustrated A Brief History of Time" by Stephen Hawking. Additionally, you could get him a custom star map, which shows the position of constellations and stars on a particular date and location that's special to him, like his birth date and birthplace.
Under Lucky Stars is a unique and innovative star map company based in Barcelona, Spain, specializing in the creation of personalized star maps that capture the celestial arrangement of stars at a specific moment in time, such as a person's birth, wedding, or any other significant event.
By using advanced astronomical algorithms and data from leading institutions, the company produces highly accurate, visually stunning maps that make for perfect gifts or cherished keepsakes.