Radio Astronomy: Limitations

radio astronomy.jpg

Astronomy is a labor of love, and radio astronomy is no different.

As I covered in my last post, radio astronomy deals with the longest wavelengths of the electromagnetic spectrum (a spectrum that includes visible light). Radio waves are not sound waves. They’re radiation just like visible light, infrared, and ultraviolet.

I’ll prove to you that radio waves can’t be sound waves. We get them from space—that’s why there’s such a thing as radio astronomy. But there’s no sound in space. Why? Sound requires something to pass through, and space is a vacuum.

So, we’ve established that radio waves are just another form of electromagnetic radiation. And astronomers love to collect any form of electromagnetic radiation. We can’t touch the stars ourselves, so it’s our only chance at learning about the cosmos.

Why? Because just about everything in the sky emits electromagnetic radiation.

Everything except black holes and a couple other things…but those are topics for another day.

But electromagnetic radiation isn’t easy to collect. And radio waves are especially hard. Continue reading

Improved Telescope Mirrors


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

Telescope Powers


Have you seen one of these guys before?

You probably have, even if you don’t recognize this brand-new innovation. This is the European Extremely Large Telescope, or the E-ELT. I know, imaginative name, huh? Anyway, it’s not all that different from one of those white observatory domes you’re used to seeing.

Astronomers keep building new observatories. They keep putting new telescopes into space—Hubble, Spitzer, and James Webb, to name a few. But the common goal of all the telescopes they build is to make telescopes that are as big as possibly possible.

Why? I mean, are astronomers just huge braggarts that like to impress us all with their big toys?

Well…I’ll admit that we astronomers have a lot of fun with our toys. But we need huge telescopes for a much better reason than bragging. Continue reading