The search for sentient alien life on other worlds has hit a speed bump, according to a new study from researchers in Germany. Scientists scan planets for certain biomarkers to confirm whether there’s a possiblity for alien life habitation. One of those markers is the presence of ozone. But, as the new research reports, ozone can get locked near the equators of exoplanets like Proxima b and Trappist 1 D. This has made it even more difficult to identify whether these planets are already inhabited.
“Absence of traces of ozone in future observations does not have to mean there is no oxygen at all,” says the study’s lead author Ludmila Carone from the Max Planck Institute for Astronomy in Heidelberg, Germany, NBC News reports.
“It might be found in different places than on Earth, or it might be very well hidden.”
Ozone is a gas composed of three oxygen atoms. On Earth, oxygen is produced by living organisms (plants, photosynthetic microbes) which makes ozone a secondary biomarker that’s similar to Earth’s on other planets. It’s distributed throughout the ozone layer which protects the Earth surface from the sun’s UV rays. So, as NBC News notes, if aliens were observing Earth from afar, they would be able to easily identify the gas.
The new research suggests that exoplanets like Proxima b don’t have an ozone layer and this may have a negative effect on their habitability. Or it may not. Things are still unclear at the moment.
“We all knew from the beginning that the hunt for alien life will be a challenge,” Carone said.
“As it turns out, we are only just scratching the surface of how difficult it really will be.”
According to Carone, these planets orbit around stars that don’t emit a lot of UV rays. These planets need these dim stars because they are tidally locked which means that one side of the planet always faces the star and the other side always faces away from it. If their stars were as bright as our sun, the worlds would be completely uninhabitable because of the extreme heat.
But even though the dim stars can make the exoplanets more conducive to alien life, these stars can be temperamental, the study says. This means that they can shoot out rays of very harmful radiation that can be destructive.
There have been a few efforts to discover whether there’s sentient life on other planets, recently. As Space.com reports scientists and artists transmitted a message to GJ 273, a red dwarf also known as Luyten’s star that is situated approximately 12.36 light-years from Earth. Luyten’s star acts as a host to two known planets. One of them is called GJ 273b which some believe may be able to support life. The message was meant to trigger a response from any life-forms that may be on the planet.