Amateur astronomy, also called backyard astronomy and stargazing, is a hobby whose participants enjoy watching the night sky (and the day sky too, for sunspots, eclipses, etc.), and the plethora of objects found in it, mainly with portable telescopes and binoculars. Even though scientific research is not their main goal, many amateur astronomers make a contribution to astronomy by monitoring variable stars, tracking asteroids and discovering transient objects, such as comets.