Who is an amateur-astronomer? We would certainly find several definitions if we tried to get answers from the audience. I am not trying to force anyone to accept my definition, in fact I do not know if I really have one. Someone who likes to read books about astronomy? Professional scientist, expert in other areas of science, but interested in astronomy? Science fiction writer who writes about space travel? Retired professional astronomer who is no longer paid for his work in astronomy? Constructor of telescopes or astronomical instruments? Well, each of these could be discussed. But we will rely, on this occasion, on common sense and take any one who is interested in astronomy and contributes to its progress either by observation or by construction of astronomical equipment and has not an official education in astronomy. He/she simply likes the idea that he/she is contributing by his/her work to our knowledge of the universe and feels proud of it.