in response to the poll...
Recently, a neutron star exploded about 50,000 light years away. (half of our galaxy) The star was said to be just bigger than New York City. The explosion disrupted our atmosphere, interrupting satellite transmissions. Recall now that this explosion was 50,000 light years away, and it was still able to affect us. If there is life out there, there might not be anymore.
A neutron star is the remnant of a star that was once several times more massive than the Sun. When their nuclear fuel is depleted, they explode as a supernova. The nearest neutron star of the type that exploded (magnestar) to us is less than 10,000 light years away. Should this explode, the shockwave would certainly cause mass extinction.
The magnetic field around a magnestar is about 1,000 trillion gauss, strong enough to strip information from a credit card at a distance halfway to the Moon.