Back in 2017 our system was scouted by a fast-moving, camouflaged, relatively small alien space-craft, dubbed 'Oumuamua. On Aug 30, this year, a new, much larger interstellar object (C/2019 Q4 (Borisov)) was detected. The several mile diameter craft is approaching from opposite the sun (an obvious attempt to avoid discovery), is obscured by a layer of gas for camouflage, and is on a trajectory bringing it within 180 million miles of Earth, close enough to identify/verify major targets and bring advanced weapons to bear. It's closest approach will be December 29th, 2019, so you have maybe three and a half months to get your affairs in order.
https://www.nationalgeographic.com/s...-just-spotted/