I wаѕ considering a Dobsonian, I live іn Southern California аnd hаνе very lіttlе light аt night tο impede mу stargazing. I аm looking tο observe manually аnd learn thе sky, wіth thе option οf possibly upgrading thе scope. I hаνе a fascination wіth asteroids аnd comets especially. Hοw large οf a scope wουld bе appropriate?
Tags: asteroid, comet, hunting/observations, ideal, need, Size, Telescope, type, would
Asteroids – forget it. New asteroids are only discovered at fainter than magnitude 19 so you need an imaging setup for these.
Comets – Binoculars will do so any telescope with clear optics is fine.
My friend David Levy has about as much comet hunting experience as anyone on Earth, and has written an excellent book on comet hunting, which goes into equipment in detail. Basically you need a rich field telescope: a wide field of view and a reasonably large aperture. A Dob mount is excellent for sweeping the sky.
For asteroids – I would go with occultations, where an asteroid passes in front a star. To do this well, it helps to have a goto scope of about 10 to 12″ aperture, a video camera and a way to record the video and time signals. In doing this type of work, your actually helping out the professionals, since they don’t have the resources (portable equipment) that the amateurs have. Data collected helps to determine an asteroids orbit, size and shape. You’ll need to travel some also, to where the occulatation is happening (these events occur in a narrow band on the earth).
For comet work, a dob would work well for you. But to do it well, plan on years worth of observing work before making your first discovery. It also helps to know the sky quite inimitably and have excellent charts.