Discover: It’s a revelation that’s both beautiful and terrifying at the same time. By Nathaniel Scharping
'Astrophysicist Erik Zackrisson from Uppsala University in Sweden arrived at this staggering figure — a 7 followed by 20 zeros — with the aid of a computer model that simulated the universe’s evolution following the Big Bang. Zackrisson’s model combined information about known exoplanets with our understanding of the early universe and the laws of physics to recreate the past 13.8 billion years.
'Zackrisson found that Earth appears to have been dealt a fairly lucky hand. In a galaxy like the Milky Way, for example, most of the planets Zackrisson’s model generated looked very different than Earth — they were larger, older and very unlikely to support life. The study can be found on the preprint server arXiv, and has been submitted to The Astrophysical Journal.
'“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,” co-author Andrew Benson told Scientific American. “It was only recently that we even had enough exoplanet data to make a model of this kind possible.”'