Astronomers have found one of the oldest known solar systems in the galaxy. While studying four years of data from NASA’s Kepler spacecraft, researchers found planets orbiting Kepler-444. The star is 117 light years from Earth and 25 percent smaller than our own sun. According to the researchers it is also 11.2 billion years old and has five Earth-size planets.

“We thus show that Earth-size planets have formed throughout most of the Universe’s 13.8-billion-year history, leaving open the possibility for the existence of ancient life in the Galaxy,” the astronomers wrote in their paper “An Ancient Extrasolar System with Five Sub-Earth-Size Planets,” published by the Astrophysical Journal.

Unfortunately, although the worlds are very old, they are not good candidates for life as we know it. All five of the planets orbit their star every 10 days or less which means that they are closer to their sun than Mercury is to ours and much too hot to support life.

Keppler-444 is close enough to be easily seen from Earth with binoculars and while it may not host habitable planets, it does answer an important question.

“This is one of the oldest systems in the galaxy. Kepler-444 came from the first generation of stars. This system tells us that planets were forming around stars nearly 7 billion years before our own solar system. Planetary systems around stars have been a common feature of our galaxy for a long, long time,” Kawaler said of the Kepler discovery in a statement.

As often happens in science, by answering a fairly simple question it raises several, more complicated ones.

Our own solar system is 4.5 billion years old, and our civilization is less than 12 thousand years old. We now know that other stars have been generating planetary systems for billions of years before ours got started. That also means that life and civilizations have had billions of years longer to evolve in other places.

If that is the case, where are they? After all, our relatively young civilization is already exploring real estate opportunities on Mars.

Physicist Enrico Fermi famously posed this question in, what has become known as, the Fermi Paradox. In what started as a lunchtime quip Fermi pointed out that, given the age of the galaxy, multiple civilizations should have sprung up and begun colonizing it by now. Even if they moved very slowly, taking hundreds of years to move from one solar system to the next, numerous civilizations would have had plenty of time to spread across the galaxy and beyond, so where are they?

Many theological, philosophical and scientific answers to Fermi’s question have been proposed but confirmation that the universe has been generating Earth-size planets for a very long time does not make answering the question any easier.

Regardless of what it means for the search for extraterrestrial life, the Kepler-444 discovery will help astronomers to study the history of the Milky Way.

“From the first rocky exoplanets to the discovery of an Earth-size planet orbiting another star in its habitable zone, we are now getting first glimpses of the variety of Galactic environments conducive to the formation of these small worlds. As a result, the path toward a more complete understanding of early planet formation in the Galaxy starts unfolding before us,” the astronomers wrote in their new paper.

Additional information about the search for exoplanets can be found on the NASA Exoplanet Archive.