In this episode of Walkabout we talk about an asteroid that is lurking out beyond the orbit of the Moon and stalking the Earth as it orbits the Sun. While it doesn’t pose an impact threat, there are plenty of little rocks out there that could do some serious damage. We also discussed the latest black hole merger observation by the LIGO gravitational wave observatory. For more on Earth’s stalker, see here. To listen to this episode, download from iTunes or directly from libsyn here.