Photo by Fidel Gonzalez.

I think every single one of us at one or another point in our lives seriously thought about aliens, I think we all question their existence regardless of our education or believe system. Every one of us is made up of atoms that were once part of an exploding star, including atomic carbon, nitrogen, and oxygen — some of the fundamental ingredients for life. Over billions of years, these ingredients condense to form gas clouds, new stars, and planets, which means that the ingredients, and therefore the potential, for life beyond Earth are scattered across the universe. What’s more, a number of recent discoveries also strongly suggest that alien life exists, either in our own solar system or beyond. In 2015 a team of scientists estimated that about 4.5 billion years ago at least one-fifth of Mars was covered in an ocean more than 450 feet deep. Any signs of life that swam in these waters could therefore be hidden in the Martian soil. But water isn’t enough. You also need time. As it happens, a study in 2014 discovered that water had existed on Mars for 200 million years longer than previously thought. What’s more, there was life on Earth the same time as some of the last lakes on Mars. Asteroids and comets are key to the formation of life on Earth, scientists think. In particular, comet impacts, likely caused amino acids to combine and form the building blocks of life. From what we know about solar-system formation, there are other comets in other planetary systems that could be doing the same thing right now. It’s possible that life can only form and thrive on Earth-like planets, which would mean our only chance of detecting aliens is on planets beyond our solar system. 5 years ago scientists detected an Earth-like planet 1,400 light-years away. Its size, orbit, sun, and age provide the “opportunity for life to arise somewhere on the surface … should all the necessary ingredients and conditions for life on this planet exist.” If there are millions of intelligent alien civilizations out there, many ask, then why haven’t we heard from them? It could be that our home galaxy, the Milky Way, is not an entirely hospitable galaxy for life, according to some scientific reports that suggests other galaxies in the universe could host 10,000x more habitable planets than the Milky Way. Either way we know in our heart of hearts that we’re not alone out there.

Story by Laurie Silvey.