At www.jpl.nasa.gov/news/news.php?release=2014-171 (see also www.nasa.gov/kepler and http://planetquest.jpl.nasa.gov/). A rocky planet weiging 17 times as much as the Earth but just over twice the size is the latest anomaly to cause some surprise to the consensus satisfied set. Know as Kepler 10c, we are told such a world should not exist – even, could not possibly exist (until it loomed out of the telescope). The thinking went – the gravitational force of such a massive body would accrete a gas envelope during formation and baloon the planet into a gas gaint similar to Neptune or Jupiter. However, Kepler 10c is composed primarily of much harder stuff – which puts a spanner into the works of the consensus on how stars and planets are formed. A NASA scientist is quoted, ' just when you think you have it all figured out, nature comes up with a surprise …' and indeed, it was a surprise.
The same story is at http://phys.org/print320928568.html … where we learn that according to theory the early universe contained only hydrogen and helium. Heavy elements that are required to bring rocky planets into being, such as silicon and iron, could only come after the first stars had exploded, scattering their crucial ingredients through space. This process should take billions of years, it is hypothesized, according to the theory, but Kepler 10c appears to be an early planet. It formed much too early – even when such heave elements were rare.