We Finally Know Why the Universe Has an Eerie Infrared Glow—And It May Have Sparked Life on Earth
You may not be able to see it, but the universe is glowing.
When viewed through an infrared lens, all of the known universe has a faint, but distinct, eerie red glow to it. For decades, scientists have been trying to figure out exactly where this comes from, and after a lot of research and theorizing, we finally have an answer.
As it turns out, this glow is caused by a molecule called benzonitrile, which is a form of polycyclic aromatic hydrocarbons (PAHs). The molecule was spotted using the Green Bank Telescope (GBT) in West Virginia, and was found not through looking at the infrared spectrum, but rather, by measuring radio waves.
This led to a unique discovery, as the benzonitrile that was found in space behaved in a radically different way to anything that astronomers were expecting. It had previously been thought that PAHs would only form around established stars with plenty of heat and energy, but the benzonitrile that was detected using radio waves was part of a cold cloud of molecular debris. What's more, there was an awful lot more of it than expected, as simulations and calculations predicted that there would four times less benzonitrile present in space than there actually appears to be.
According to molecular astrophysicist Christine Joblin of the University of Toulouse:
It's always fun when scientists are proved wrong because it means there's something new to be investigated, studied, and discovered. We now finally have an answer to the question of why space gives off a slight infrared glow.
What's even more intriguing is the fact that benzonitrile is an organic compound. On Earth, it's present primarily in animal or plant-made matter. Our food, both vegetarian and otherwise, contains benzonitrile, as does cigarette smoke (a byproduct of burning tobacco leaves) and even many forms of pollutants that come from fossil fuels.
It's unlikely that the benzonitrile that's present throughout space is the consequence of some alien species polluting and smoking, but it does suggest that there are multiple ways in which organic matter can come into existence.
If benzonitrile can exist in large quantities in space, you have to wonder what other organic compounds might be floating around out there.
Increasingly, scientists are entertaining the idea that exposure to cosmic rays could be key in producing the compounds known as the "building blocks of life" that kickstarted evolution on our own world, and the presence of benzonitrile in the vaccum of space is a nice reminder that, in a universe as big and diverse as our own, there could be anything out there, just waiting to be discovered.
Who knows what else is hiding out in the inky black, pretending to be nothing more than a quiet infrared glow?