It was discovered in 2004 by a team headed by mike brown of caltech at the palomar observatory in the united states and independently in 2005 by a team headed by jose luis ortiz moreno at the sierra nevada observatory in spain though the latter claim has been contested. Nasa sol the model for finding stars with habitable planets. Over the past several years astronomers increasingly have been using three somewhat overlapping terms to describe a range of extra solar planets that have been or may soon be found.