Why NASA hasn’t found alien life yet even with $10bn James Webb Space Telescope

Humanity's obsession with discovering alien life - or vice versa - is unparalleled. From The War of the Worlds to Mars Attacks and Venom, thousands of films and television shows have cemented our obsession with what might lurk on other planets.

But there's a very real reason why humankind has struggled when it comes to exploring the cosmos and stumbling across life from a place that isn't Earth, with NASA now moving to explain this to us.

The issue has even been given its own term, dubbed the Fermi paradox. Named after scientist Enrico Fermi, it notes the huge disparity between the lack of evidence that advanced alien life exists out there and the apparent likelihood that it does in fact exist.

With billions of stars in our very own Milky Way similar to the Sun, and then what lies further afield, the scientific chances for what is needed to allow life to prosper is at odds with humanity's inability to find that life.

This is increasingly the case as technology gets better and better, through the likes of NASA's $10 billion (£8 billion) James Webb Space Telescope (also known as the JWST or simply, Webb).

Launched into space two years ago, Webb is travelling the galaxy in search of all things new to provide greater understanding of the likes of black holes and finding signs of extraterrestrial life.

CGI of the James Webb Space Telescope floating in space (NASA/Getty Stock Images)

Among its discovers, Webb has found planets with all the evidence pointing towards 'signs of life', with investigatory work now under way.

Last week, NASA said that the JWST has been 'busy observing a few small, potentially habitable planets, and astronomers are now hard at work analysing' the data.

With this in mind, the American spacey agency has spoken to two doctors who help run the Webb programme to explain what is happening and why finding evidence of life is bloody hard work.

Writing in a new blog post, Doctors Knicole Colón and Christopher Stark, both Webb scientists at NASA’s Goddard Space Flight Center, explained why it is 'extraordinarily difficult' to find alien life.

Surely there is life out there in some form (Getty Stock Images)

“The potentially habitable worlds Webb is observing are all transiting exoplanets, meaning their orbits are nearly edge-on so that they pass in front of their host stars," they said.

"Webb takes advantage of this orientation to perform transmission spectroscopy when the planet passes in front of its star. This orientation allows us to examine the starlight filtered through the atmospheres of planets to learn about their chemical compositions.

"However, the amount of starlight blocked by the thin atmosphere of a small rocky planet is tiny, typically much smaller than 0.02%. Simply detecting an atmosphere around these small worlds is very challenging.

"Identifying the presence of water vapour, which may bolster the possibility of habitability, is even harder. Searching for biosignatures (biologically produced gases) is extraordinarily difficult, but also an exciting endeavour."

They also explain that there is 'currently only a handful of small, potentially habitable worlds that are considered accessible to atmospheric characterisation with Webb'. This includes planets known as LHS 1140 b and TRAPPIST-1 e; two of NASA's biggest hopes in finding life on other planets.

Another such planet is the super-Earth-size planet LHS 1140 b and with that comes problems.

To find potential evidence of gases produced by organisms, the JWST would have to collect data from the planet going around its sun up to 50 times, which would take up to 200 dedicated hours of Webb's time.

And all that does is provide a base point from which readings could be taken to detect the likes of ammonia, phosphine, chloromethane, and nitrous oxide, in the best-case scenario of a clear, cloud-free atmosphere.

So basically, it's incredibly hard to get the results in terms of time, observation conditions, and then scientific analysis. One thing that is for sure, though, is that the world's experts in the field are certainly giving it their best shot.