Sometimes, breakthroughs in science don't have to be about discovering something new, it could also be about how old ideas are applied in new ways. That's the case in this new development, which applies radar technology to interplanetary geology.

This tech comes from the European Space Agency, and is called the MARSIS, the Mars Express radar sounder. The technology recently allowed scientists to figure out the composition of the Martian subsurface.

Before, scientists held the idea that they would need to send landers to dig on the surface of other celestial bodies so that they could figure out the composition of the subsurface. The new technology doesn't even require the shuttle to land to do it.

The idea was never tried before because no one knew if it would work. Trying to use a radar sounder from orbit could have presented a number of problems. For instance, the subsurface of the planet might be too opaque for radar waves.

Now that the tech has been proven to be successful, scientists hope to be able to use it on other bodies, like Jupiter's moon, Europa. They should try and explore Mars more to figure out if there are any hidden bunkers.