The term "amateur astronomer" refers to someone who engages in the hobby or passion of observing and studying celestial objects, such as stars, planets, galaxies, etc., without any professional or financial motivations. These individuals typically pursue their interest in astronomy for personal enjoyment, education, and exploration, using a variety of telescopes and other equipment to observe the night sky. They may also participate in activities like astrophotography, observing meteor showers, and contributing data to scientific research projects. In short, an amateur astronomer is someone who loves and studies celestial objects out of personal interest rather than for any professional or commercial purposes.