An article in Science concerns mysterious burst of radio waves from billions of light years away – which has caused some speculation (see http://phys.org/print292164806.html
The Science article claims the bursts of energy originate from an extreme astrophysical event involving neutron stars – or black holes, extreme events involving large amounts of mass or energy as the source. A single burst of radio emission detected six years ago led to the discovery, after four years or so, of many more of them. It is now being suggested one of them godes off every 10 seconds somewhere in the universe – which is an awful lot of extreme astrophysical events.
At http://phys.org/print292230904.html … could Earth have more than one Moon? This is a contemplative post on asteroids in resonant orbit with the Earth.