Science Documentary/YouTube screenshot by Chris Matyszczyk/CNET

I've never thought of humanity as being especially advanced.

Somehow, we struggle so much with such basic things as thermostats and civility that I cannot imagine we've been around since either the Big Bang or God's Big Finger Pressing Play.

Harvard astrophysicist Abraham Loeb gets the feeling that we are one of the last to the universe party.

As Space.com reports, Loeb's research suggests that a mere 15 million years after the Big Bang, alien microbes might have happily survived.

He said: "When the universe was 15 million years old, the cosmic microwave background had a temperature of a warm summer day on Earth. If rocky planets existed at that epoch, then the CMB could have kept their surface warm even if they did not reside in the habitable zone around their parent star."

Traditional scientific thinking offered that the first stars formed out of hydrogen and helium. There weren't any so-called heavy elements that would have assisted planet formation.

Loeb asked the simple question: What if there were some heavy elements? There might have been huge stars exploding and emitting them.

Any planets that might have resulted from these explosions would have enjoyed the warmth of cosmic microwave background radiation. Therefore, water may have been present and life forms may have existed.

This puts into question the idea of "Goldilocks Zones," the areas of the universe that are said to be the right distance from stars -- not too warm, not too cold, but just right -- in order for the existence of liquid water to have been possible.

But wait. How on earth can we ever know whether Loeb's theory might have some truth attached to it?

He suggests "searching for planets with atmospheric bio-signatures around low-metallicity stars in the Milky Way galaxy or its dwarf galaxy satellites."

In essence, if researchers find planets in the vicinity of stars that have merely a few heavy elements, then these might once have been analogous to the very earliest of planets.

Understanding what may or may not have happened billions of years ago is not exactly a simple task.

But one sign that Loeb might be onto something is that his fellow scientists aren't pooh-poohing it.

Water might have existed in many more places than first imagined. So who knows who or what might have existed in times gone far by?

And who knows what might still exist and be visiting us regularly, only to leave, shaking their heads and bodies in derision?