Here are a couple of simple basic facts that will help you avoid the pitfalls of “hobby killer” telescopes. The aperture is the diameter of the main lens or mirror of the telescope. It is closely related to the size of the front opening of the telescope and I use this characteristic to simplify the concept in this video. Aperture is always the first number you see in the specification of a telescope. When comparing telescopes you can quickly judge the effectiveness of the telescope by that number, though there are many other parameters that might also be important. It's a good place to start.
I am a retired Astronomy Professor. I do not make any money or benefit in any way from my recommendations. Unlike many KZfaq reviewers, I am not an Amazon affiliate. I make nothing when you make a purchase.
My video on the Best Beginner Telescopes:
• Best Beginner Telescopes
Beginner Binoculars for Astronomy:
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