Improved Telescope Mirrors

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When it comes to telescopes, bigger is always better.

Bigger means more light-gathering power and better resolution. And a longer telescope—meaning, a longer focal length—can actually do wonders for your magnification power.

Light-gathering power, by the way, just means how much light a telescope can gather—and it works the same way as rain in a bucket. The bigger the bucket, the more rain you can collect.

And resolution means how much detail you can see in an image. It goes hand in hand with light-gathering power—more light means more detail.

So bigger, for serious astronomers, is the way to go. Until your mirror starts sagging.

Yeah…that’s a bit of a problem. But nowadays, we can fix it. Continue reading

Improved Reflecting Telescopes

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Can you tell the difference between these two telescopes?

I’ll give you a hint. They are both reflectors. I know I wrote before that you’ll normally find the eyepiece (the little bit tacked onto the telescope tube) on the side with reflectors, but as you can see here, this isn’t always the case.

Here’s another hint. The mounting setup isn’t the difference I’m talking about. I realize the most obvious difference is probably that one is on a “fork mount” (right) and the other is on an equatorial mount (left), but I’m thinking of something related to the optics.

Don’t worry, we’ll talk about these two mounting systems in a later post.

So, can anyone venture a guess and tell me what’s different about these two telescopes? Continue reading

Refracting & Reflecting Telescopes

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Right next to light, the telescope is an astronomer’s most valuable tool. There are so many different varieties of telescopes, it can be hard to keep them all straight. But they can all be sorted into a few basic types, and that makes choosing one a lot simpler.

Two very common types are reflectors and refractors, and each one in the image above is one of these. You can tell a reflector by its cylindrical design. They all look like cylinders, you say? Well…refractors are a little bit different.

Take the two telescopes on either end of this lineup, for instance. These two—the far left and the far right—are refractors. And you may notice that, unlike most of the rest, they’re not perfect cylinders.

Look closely. You’ll see that, not only is the end pointing up a bit wider than the rest of the telescope, but there’s a little tiny piece tacked onto the end. That same little tiny piece is tacked onto the side for the reflectors.

Every reflector and every refractor can be recognized by these basic qualities. But what they do with light is more important. Continue reading