Theory Ties Radio Signal to Universe's First Stars - NYTimes.com

Your problem could be one of two things. Either you're boggled by radio energy in space, or you don't understand how a star/black hole could emit radio energy.

Okay, really basic lesson in electromagnetism and wave theory. Light travels in space, that much you grasp. Radio energy also travels in space. It's just a question at what frequency the energy is travelling.

Here's a brief primer

Your problem is thinking about how sound travels. Now, as it happens, the sun emits prodigious amounts of energy in the audible sound frequency.. Problem is, sound energy reaches our ears through the medium of air, or water, or even the ground in the case of earthquakes. In space, obviously there's no air, so the sound energy doesn't propagate efficiently. But you already know light and sound propagate at different speeds, that's why lightning at a distance is seen before it's heard.

Radio "telescopes" are merely very large directional antennas, rather like satellite TV dishes. They have big pickup to absorb the reflected energy. They're incredibly useful, far more useful than a telescope only operating in the visual spectrum.

Oh, by the way, a lot of that static you hear on the radio at night? That's largely the planet Jupiter. It emits huge amounts of radio energy. No human being will ever fly to Jupiter, the planet emits so much energy it would kill anyone. If things had gone a little differently, Jupiter might be a star. But in many ways it does behave like the early phases of a star as it's forming. It's just hasn't turned on the hydrogen bomb part of a star, it lacks the mass.

The universe is full of radiated energy. One of the truly terrible things about a black hole is this, it's not black at all while it's consuming something. It emits two ghastly plumes of superaccelerated X-rays from its poles and blasts all kinds of radiation, lots of it is microwave energy, too, as the atoms are torn apart.

What we call "radio" energy is a huge swath of the electromagnetic spectrum. Just like light can travel through space, so can radio waves.

Blaise, thanks for the info! I thoroughly enjoyed and appreciated the science lesson. :)

What insanely awesome stuff!