We continue our search for planets that can support alien life, but how exactly can we confirm whether said life actually exists on these identified worlds?
While the majority of people have their sights focused on Mars as a possibility for human expansion, the reality of the matter is that there are a number of exoplanets that exist in a potentially habitable zone. The problem is that, unlike Mars, these planets exist thousands of light years away.
In addition to making human exploration a near-impossibility, it’s also quite difficult to actually determine whether alien life exists on these planets – making the search that much more difficult as our view extends further outward.
However, despite the fact that it’s extremely difficult to search for alien life on these faraway planets, we do have some options that we can turn to in order to discover whether there is actual activity in these habitable zones.
One possible solution for the problem lies in looking for biosignatures or signs of lights in the atmosphere. This would be things such as oxygen or other gases necessary for life on Earth. Our next-gen telescopes will be able to search for these compounds while scanning the atmosphere of exoplanets, but it’s really just a small piece of the overall picture.
Even if we’re to find an exoplanet with oxygen and the ability to support life, that doesn’t necessarily mean that alien life will actually be there. That’s why researcher’s from the University of California, Riverside’s Alternative Earths Astrobiology Center set to work developing a new quantitative framework which would give a better and more dynamic overview and potentially allow us to discover alien life.
The process, according to a release from the university, revolves around taking advantage of the planet’s changing seasons in order to predict biosignatures and perhaps even discover alien life.
When the Earth orbits around the sun, the tilted axis is responsible for giving us changes in weather and length of day around the world. In addition to giving certain parts of the world more sunlight at certain parts of the year, it also has an effect on the content of gases in the atmosphere.
The group of researchers are under the impression that exoplanets with extremely elliptical orbits might also witness similar seasonal patterns.
“Atmospheric seasonality is a promising biosignature because it is biologically modulated on Earth and is likely to occur on other inhabited worlds,” lead author Stephanie Olson said in a statement.
“Inferring life based on seasonality wouldn’t require a detailed understanding of alien biochemistry because it arises as a biological response to seasonal changes in the environment, rather than as a consequence of a specific biological activity that might be unique to the Earth.”
During the study, the authors identified both the benefits and risks that were associated with the seasonal rise and fall of different gases and created a scientific model in order to see how oxygen might be fluctuating.
“It’s really important that we accurately model these kinds of scenarios now, so the space and ground-based telescopes of the future can be designed to identify the most promising biosignatures,” Edward Schwieterman, a NASA Postdoctoral Program fellow at the university, added.
While this still doesn’t provide conclusive proof of the existence of alien life, it at least gives us a better sense of whether exoplanets are truly analogous to our own. There’s certainly a possibility that some unique species could function differently to what we’ve seen before, but all we have to go off of is our personal understanding of how life functions.
It may never be possible for us to actually visit these exoplanets due to their incredible distance, but through scientific advancement, we may be able to eventually peer into their surface and make a decision as to whether or not they support alien life.
The study, titled “Atmospheric Seasonality As An Exoplanet Biosignature,” was published May 9 in the Astrophysical Journal Letters.