Astronomers are vigilantly scanning the skies for asteroids that veer into Earth’s solar system neighborhood. But, some are hidden. Most asteroids — leftover rubble from our solar system’s formation some 4.6 billion years ago — orbit the sun between Mars and Jupiter. Millions exist out there. But in the inner solar system, asteroids are obscured by the blinding glare from the sun. Now, a new survey of space rocks in regions around the orbits of Venus and Mercury have spotted sizable asteroids in this elusive zone of space. One is nearly a mile wide, the type of “planet-killer” rock that would decimate life on Earth. Fortunately, these rocks don’t currently pose any danger to our planet, nor will they for the foreseeable future — though over centuries, or much longer, one of the asteroids’ orbits may change and potentially pose a threat.