Nasa detects TWO space rocks heading towards Earth – but it still can’t work out whether one is an asteroid or a comet This week a comet that started life in the outer reaches of our solar system will be visible from Earth for the first time, as it approaches our planet’s orbit. Another recently-discovered object, called 2016 WF9, has also been taking a scenic tour of our solar system, approaching Jupiter’s orbit at its greatest distance from the sun.