Astronomical Survey

Additional Geekiness provided by Astrobiology. Looks like a science post day.

A three year sky survey seeking large planets outside 5 astronomical units (1 AU is the distance from the Sun to the Earth) has been completed and the study finds that our own solar system is a pretty rare example, with its gas giants being outside this distance. All of the 54 nearby systems surveyed had no Jupiter or better sized planets outside this distance, which has important implications for the search for life outside the solar system.

"Astronomers who used powerful telescopes in Arizona and Chile in a survey for planets around nearby stars have discovered that extrasolar planets more massive than Jupiter are extremely rare in other outer solar systems. The finding is an important step in our understanding of extrasolar worlds and the potential for discovering habitable planets around distant stars."

It is thought that the presence of Jupiter and the other outer gas giant planets in such distant orbits "protected" Earth from even more violent impact events due to their gravity either capturing or repelling many potential stellar objects from travelling deeper into our solar system. More than 230 "hot super-Jupiters" have been found in tight orbits around their parent stars, but this study needed a new technique to examine stars for planets further distant, and used two giant telescopes in Arizona and Chile with methane detection equipment for the task.