NASA: most habitable planets don't exist yet

Based on data from the Hubble Space Telescope, researchers have determined that most of the Earth-like habitable planets that will fill our universe don't yet exist — our own planet was among the first batch of habitable planets that will dot the universe. Said the author of the study, Peter Behroozi, "Compared to all the planets that will ever form in the universe, the Earth is actually quite early."

The study indicates that of all the habitable planets that will form in the universe, only 8% or so of them were present when our solar system first formed some 4.6 billion years ago. Of the remaining 92-percent of habitable, Earth-like planets, most of them haven't even yet been born.

Earth got in on the process early, and it'll be long gone before the last star burns out in 100 trillion years or so. At this point in time, estimates place Earth-sized planets in the Milky Way at around the one billion number, and it is assumed most of those planets are rocky. Expanding one's consideration to the other galaxies in the known universe increases that number to ridiculous proportions.

It is anticipated that future Earth-like planets — that is, planets like our own that sustain life — will be found in dwarf galaxies and massive galaxy clusters alike. Before then, though, we play an important role in existence. Due to Earth's early formation, we're able to trace the evolution of galaxies and existence from the big bang onward. NASA says that in about 1 trillion years, due to space's expansion, evidence of such cosmic evidence will be "all but erased."

SOURCE: NASA