Complex sentence: On September 28,2017 there is a 1 in 260 million chance it will impact Earth, but the nominal (best-fit) solution shows that could be 1.5AU from Earth on 28 Sep 2017.
Split into simpler sentences: On September 28,2017 there was a 1 in 260 million chance it could impact Earth. The nominal (best-fit) solution shows that should be around 1.5AU from Earth on 28 Sep 2017.