Space is supposed to be silent, right?

Well,#maybe not as silent as we thought.

Astronomers have detected something strange coming from# deep space.

An unexplained radio signal that is six times louder than expected.

They call# it the space roar.

Back in 2006, NASA's ARCADE experiment, short for Absolute Radiometer for# Cosmology, Astrophysics, and Diffuse Emission, was launched high above Earth on a balloon to# study faint radio waves from the early universe.

But instead of weak background signals, the# instruments picked up a massive radio hum, a bit of powerful cosmic noise that just couldn't# be traced from any known source.

And it wasn't coming from our galaxy, even.

Yeah.

This roar# is a type of radio wave.

It's invisible to human eyes and ears, but detectable with sensitive# antennas.

Scientists checked everything that they knew of: distant galaxies, black holes,# even leftover radiation from the Big Bang, but nothing could fully explain it.

It's still# one of astronomy's big unsolved mysteries.

Some think it might come from millions of# faint, undetected galaxies scattered across the cosmos.

Others wonder if it points# to something entirely new, a cosmic phenomenon that we've just never seen before.

Whatever is# causing the space roar, one thing is for sure, the universe isn't as quiet as we imagined.

So# stay curious, Star Gazers.

I'm Trace.

Keep looking up!

Do you want to know more about the night# sky, space exploration, astronomy?

Let us know down in the comments what you want to know.

And# in the meantime, click this video to learn more.