When you stop to think about the development of life on Earth over the past four billion years, it can seem like an absolute miracle that anything managed to survive. Researchers have long wondered if there were other planets in the universe that could host life like Earth does, but so far have discovered no concrete evidence of any such planet.

According to a report from Discovery News, however, this may be about to change. Given our level of intelligence, we would have expected to be contacted or at least shown evidence of other intelligent life in the universe. As we become increasingly aware of how large the universe actually is, the Fermi Paradox becomes even more pronounced: where is all of the intelligent life?

A new study from researchers working with NASA and the Hubble Space Telescope and the Kepler Space Telescope suggests that Earth may have given way to life much earlier than other planets. This suggests that we aren’t isolated by space, but by time; all other intelligent life in the universe may very well have not developed just yet.

The study focuses on determining how likely it is for other habitable worlds to develop throughout the universe. When Earth was first formed, there were only 8 percent of the potentially habitable planets that could possibly form since the universe existed. In other words, 92 percent of the habitable worlds the universe could possibly create have not formed yet.

Based on estimates of the concentrations of different elements released by the big bang, researchers were able to determine where most of these materials would have settled and how many of them could have been molded into habitable planets.

The Milky Way may be all done forming planets, but researchers have looked to other galaxies for the next Earth 2.0. Giant galaxy clusters or dwarf galaxies with star-forming gases could very well give rise to more habitable planets, and maybe we will even have the pleasure of meeting their inhabitants one day.

For now, we remain alone in the universe to the best of our knowledge.

The press release submitted by the Hubble Telescope research team can be found here.