Earth may just be a tiny speck in a vast universe, but new scientific research has given us the reassuring news that we are, at least, special.Astronomer Erik Zackrisson, from Uppsala University in Sweden, has used computer simulations to create a model of all the terrestrial planets likely to exist in the universe, the Scientific American reports.The model found there could be as many as 700 quintillion planets in the universe but none quite like Earth – with its relative youth and place in the Milky Way galaxy.The findings appear to fly in the face of our current thinking about our planet, as ascribed by the ‘Copernican principle,’ which states that Earth doesn’t hold a privileged position in the cosmos.
To create his own digital mini-universe, Mr Zackrisson started out by inputting the earliest galaxies, along with exoplanet data they had from probes such as Kepler.Then, using our knowledge of physics, fast-forwarded through 13.8 billion years of cosmic history.“It’s kind of mind-boggling that we’re actually at a point where we can begin to do this,” co-author, Andrew Benson from the Carnegie Observatories in California, said.Although the team believed their findings were accurate, Mr Benson admitted they were just a preliminary guess at what the cosmos might hold.
“It’s certainly the case that there are a lot of uncertainties in a calculation like this. Our knowledge of all of these pieces is imperfect,” he said.“Everything we know about exoplanets is from a very small patch in our galaxy,” Mr Zackrisson said.Nearby stars generally have similar characteristics, including the number of heavy elements they contain, so the team had to extrapolate to guess how planets might form around stars with fewer heavy elements, for example, he said.
The researchers concluded that Earth is a mild violation of the Copernican principle.But, commenting on the research, Cosmologist Max Tegmark from the Massachusetts Institute of Technology, told the Scientific American he believes the Earth is a “colossal” violation of the Copernican principle because of its young age.“If you have these civilizations that had a 3.5-billion-year head start on us, why haven’t they colonized our galaxy?” Mr Tegmark said.“To me, the most likely explanation is that if the planets are a dime a dozen, then highly intelligent life evolves only rarely.”