Apparent magnitude is a rather complex way to determine the brightness of a star. Quoting the introduction text from the linked to Wikipedia page: The apparent magnitude (m) of a celestial body is ...
I've had a dobsonian telescope for a while now, but I've never been able to collimate it. I thought I had it collimated once, but when I looked through it the star didn't look right, it looked kind ...
I have a Plettstone 18" Dobsonian telescope and use a Howie Glatter tuBlug, laser collimator, and Square Grid Projection Attachment to adjust the mirrors. Proper collimation requires an accurate ...
How do I observe the Sun safely, with tools I could build myself and without breaking the bank? If I wanted to build a Sun funnel on my own and use it on my enthusiast grade telescope, how would I do ...
I have a Plettstone 18" Dobsonian telescope with GOTO and clock drive that runs off a 12 volt cigarette lighter adapter. What is an appropriate battery to use to run this overnight while viewing all ...