Watching the “Alien Planets” episode of the History Channel’s Universe program, we learn an interesting discovery: planets around a pulsar (for example PSR B1257+12). That’s impossible – a pulsar is formed after a massive supernova explosion, an explosion powerful enough to destroy any planet.
However, three small rocky planets were discovered. What they now hypothesize is that these planets formed from the debris of destroyed parent planets. If this is so, it is further evidence that planets can form under extreme conditions; Gravity tends to pull debris together, a natural consequence of matter and gravity. Therefore, planets are probably very, very common.
By the way, life on a planet around a pulsar is highly unlikely – the radiation flooding the system is too high, especially if the planet is in the path of emission rays from the pulsar’s magnetic poles.
